Carbon steel 1045 1045 (UNS G10450, AISI 1045)
Fe balance
Also known as UNS G10450, AISI 1045, SAE 1045, JIS S45C, ASTM A29, ASTM A576 · 3 more
AISI 1045 is a plain medium-carbon steel: iron with about 0.43 to 0.50 percent carbon and 0.60 to 0.90 percent manganese.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Strength, cold drawn
> 690 MPa
Strength, hot rolled
> 690 MPa
Strength, as rolled
> 540 MPa
Strength, annealed
> 540 MPa
Stiffness
190 to 210 GPa
Recipe, share of the weight
- Fe balance (the rest)Iron
- C 0.43 to 0.5%Carbon
- Mn 0.6 to 0.9%Manganese
- P max 0.040Phosphorus
- S max 0.050Sulfur
- Si max 0.100Silicon
Best for
Forged or machined axles, shafts, gears and machine parts that need more strength than low-carbon steel, and that are coated against rust
Weakest at
Rust in moist air and salt unless it is coated, and strength that depends on whether the bar was cold drawn, hot rolled, normalised or annealed
Risk at a glance
- People Low. PubChem hazards are for the metals
- If it fails No data. No failure risks recorded
- Corrosion No data. No corrosion data recorded
Quick facts: 1045 (UNS G10450, AISI 1045)
| Property | Value | Basis |
|---|---|---|
| Yield strength | 300 to 540 MPa | 7 sourced values across conditions |
| Tensile strength | 552 to 700 MPa | 7 sourced values across conditions |
| Young's modulus | 190 to 210 GPa | 1 sourced value |
| Hardness (Brinell) | 170 to 210 HB | 1 sourced value |
What is the yield strength of Carbon steel 1045?
Carbon steel 1045 has a yield strength of 300 to 540 MPa. The range covers 7 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the tensile strength of Carbon steel 1045?
Carbon steel 1045 has a tensile strength of 552 to 700 MPa. The range covers 7 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the Young's modulus of Carbon steel 1045?
Carbon steel 1045 has a Young's modulus of 190 to 210 GPa. The source and test conditions are listed in the properties table on this page.
What is the hardness of Carbon steel 1045?
Carbon steel 1045 has a Brinell hardness of 170 to 210 HB. The source and test conditions are listed in the properties table on this page.
What are the other names and codes for Carbon steel 1045?
Carbon steel 1045 is also written as UNS G10450, AISI 1045, SAE 1045, JIS S45C, ASTM A29, ASTM A576. Each code is printed in the source listed beside it in the designations table.
What is Carbon steel 1045 used for?
Uses recorded in the sources include Axles, clutch members and shafts; Gears, pinions and stud bolts; Heavy machinery parts.
Why it exists
AISI 1045 is the common medium-carbon steel. It is stronger than low-carbon steel and can be heat treated for more strength, so it is chosen for shafts, axles, gears and machine parts. Its strength depends on the condition the bar was made in, so every figure in this profile is kept with its own condition.
Where it's used
Shafts, axles and clutch members
Voestalpine says heavy forgings in the normalised condition suit automotive and general engineering, such as axles, clutch members and shafts.
Gears, pinions and stud bolts
Metal Supermarkets lists stud bolts, ordinary shafts, pinions and gears among its typical applications.
Heavy machinery
MaterialWelding lists heavy machinery such as drilling rigs, oil rigs and mining equipment among the uses of AISI 1045.
Recipe
Fe balance; 0.43 to 0.50 C, 0.60 to 0.90 Mn, max 0.040 P, max 0.050 S, max 0.100 Si (wt%)
AISI 1045 is iron with 0.43 to 0.50 percent carbon and 0.60 to 0.90 percent manganese, with at most 0.040 percent phosphorus and 0.050 percent sulfur (iCAST AISI 1045 sheet). It is sold as hot-rolled or normalised bar, and also as cold-drawn bar (voestalpine, MaterialWelding).
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Iron Fe | balance (the rest) | The matrix of the steel. Iron makes up the rest of the composition. |
| Carbon C | 0.43 to 0.5% | Sets the strength and hardness. Medium-carbon steel balances ductility and strength (Wikipedia, Carbon steel). |
| Manganese Mn | 0.6 to 0.9% | Adds hardenability (Wikipedia, Carbon steel, describes manganese additions for hardenability). |
| Phosphorus P | max 0.040 | Impurity held to a maximum limit. |
| Sulfur S | max 0.050 | Impurity held low. Trace sulfur makes steel red-short, brittle and crumbly at high working temperatures (Wikipedia, Carbon steel). |
| Silicon Si | max 0.100 | Held to a maximum limit (iCAST). Other sources print a higher limit; see gaps. |
Weight shares are as printed in the sources.
What it can do
Strength, cold drawn
> 690 MPa
measured
Cold-drawn bar under 16 mm has a minimum tensile strength of 690 MPa and a minimum yield strength of 540 MPa (voestalpine reference limits).
Strength, hot rolled
> 690 MPa
measured
Hot-rolled bar under 250 mm has a tensile range of 570 to 700 MPa and a minimum yield strength of 300 MPa (voestalpine).
Strength, as rolled
> 540 MPa
measured
Typical as-rolled bar gives 90000 psi tensile and 59000 psi yield (Metal Supermarkets, typical values).
Strength, annealed
> 540 MPa
measured
Typical annealed bar gives 80000 psi tensile and 48000 psi yield (Metal Supermarkets, typical values).
Stiffness
190 to 210 GPa
measured
Elastic modulus is 190 to 210 GPa, with no condition stated (Total Materia).
How it compares
AISI 1045 is a medium-carbon steel. Metal Supermarkets says heat treatment gives it more strength than lower-carbon steels can reach. Its figures depend on condition: the minimum yield for cold-drawn bar under 16 mm is 540 MPa, against 300 MPa for hot-rolled bar under 250 mm (voestalpine). Typical as-rolled and normalised bar give yield values of 59000 and 58000 psi (Metal Supermarkets). Every value here keeps its condition.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.
| Measurement | 1045 (UNS G10450, AISI 1045) | A36 (UNS K02600) | 1018 (UNS G10180, AISI 1018) | 1215 (UNS G12150, AISI 1215) | 4130 (UNS G41300) | 4140 (UNS G41400) | 1010 (UNS G10100, AISI 1010) | 1070 (UNS G10700, AISI 1070, SAE 1070) | 4340 (UNS G43400) |
|---|---|---|---|---|---|---|---|---|---|
| Physical and electrical | |||||||||
| brinell hardness | 170 to 210 HB13 | no data | no data | no data | no data | no data | 95 to 105 HB | no data | no data |
| Other measurements | |||||||||
| yield strength | > 540 MPa1 | > 36 ksi | 370 MPa | 415 MPa | 635 MPa | > 740 MPa | 190 MPa | > 390 MPa | > 665 MPa |
| ultimate tensile strength | > 690 MPa2 | 58 to 80 ksi | 440 MPa | 540 MPa | 820 MPa | 930 to 1080 MPa | 350 MPa | 640 MPa | 850 to 1000 MPa |
| elongation | > 8 %3 | > 21 % | 15 % | 10 % | 25.5 % | > 12 % | 30 % | > 10 % | > 13 % |
| yield strength | > 510 MPa4 | > 36 ksi | 370 MPa | 415 MPa | 635 MPa | > 740 MPa | 190 MPa | > 390 MPa | > 665 MPa |
| ultimate tensile strength | > 650 MPa5 | 58 to 80 ksi | 440 MPa | 540 MPa | 820 MPa | 930 to 1080 MPa | 350 MPa | 640 MPa | 850 to 1000 MPa |
| elongation | > 8 %6 | > 21 % | 15 % | 10 % | 25.5 % | > 12 % | 30 % | > 10 % | > 13 % |
| yield strength | > 500 MPa7 | > 36 ksi | 370 MPa | 415 MPa | 635 MPa | > 740 MPa | 190 MPa | > 390 MPa | > 665 MPa |
| ultimate tensile strength | > 640 MPa8 | 58 to 80 ksi | 440 MPa | 540 MPa | 820 MPa | 930 to 1080 MPa | 350 MPa | 640 MPa | 850 to 1000 MPa |
| elongation | > 9 %9 | > 21 % | 15 % | 10 % | 25.5 % | > 12 % | 30 % | > 10 % | > 13 % |
| yield strength | > 300 MPa10 | > 36 ksi | 370 MPa | 415 MPa | 635 MPa | > 740 MPa | 190 MPa | > 390 MPa | > 665 MPa |
| ultimate tensile strength | 570 to 700 MPa11 | 58 to 80 ksi | 440 MPa | 540 MPa | 820 MPa | 930 to 1080 MPa | 350 MPa | 640 MPa | 850 to 1000 MPa |
| elongation | > 14 %12 | > 21 % | 15 % | 10 % | 25.5 % | > 12 % | 30 % | > 10 % | > 13 % |
| yield strength | 59000 psi14 | > 36 ksi | 370 MPa | 415 MPa | 635 MPa | > 740 MPa | 190 MPa | > 390 MPa | > 665 MPa |
| ultimate tensile strength | 90000 psi15 | 58 to 80 ksi | 440 MPa | 540 MPa | 820 MPa | 930 to 1080 MPa | 350 MPa | 640 MPa | 850 to 1000 MPa |
| elongation | 26 %16 | > 21 % | 15 % | 10 % | 25.5 % | > 12 % | 30 % | > 10 % | > 13 % |
| yield strength | 58000 psi17 | > 36 ksi | 370 MPa | 415 MPa | 635 MPa | > 740 MPa | 190 MPa | > 390 MPa | > 665 MPa |
| ultimate tensile strength | 87000 psi18 | 58 to 80 ksi | 440 MPa | 540 MPa | 820 MPa | 930 to 1080 MPa | 350 MPa | 640 MPa | 850 to 1000 MPa |
| elongation | 28 %19 | > 21 % | 15 % | 10 % | 25.5 % | > 12 % | 30 % | > 10 % | > 13 % |
| yield strength | 48000 psi20 | > 36 ksi | 370 MPa | 415 MPa | 635 MPa | > 740 MPa | 190 MPa | > 390 MPa | > 665 MPa |
| ultimate tensile strength | 80000 psi21 | 58 to 80 ksi | 440 MPa | 540 MPa | 820 MPa | 930 to 1080 MPa | 350 MPa | 640 MPa | 850 to 1000 MPa |
| elongation | 30 %22 | > 21 % | 15 % | 10 % | 25.5 % | > 12 % | 30 % | > 10 % | > 13 % |
| elastic modulus | 190 to 210 GPa23 | 200 GPa | 200 GPa | 200 GPa | 205 GPa | 205 GPa | 210 GPa | 190 GPa | 190 to 210 GPa |
Why choose it, and why not
Good for
- Forged or machined shafts, axles and gears that need more strength than low-carbon steel (voestalpine, Metal Supermarkets)
- Machine parts cut in the normalised condition, which MaterialWelding prefers for machining
Watch out for
- Moist air and salt cause rust, so paint or coat outdoor parts (Wikipedia, Carbon steel)
- Sources disagree on weldability: MaterialWelding says good weldability with preheat, while Metal Supermarkets says welding qualities are limited
- Minimum limits (voestalpine) and typical values (Metal Supermarkets) are different kinds of figure, so they are kept apart
- Silicon and phosphorus limits differ between sources (see gaps); the recipe uses the iCAST AISI 1045 sheet
AISI 1045 is a strong, widely available medium-carbon steel for axles, shafts and gears. It rusts in moist air and salt, so coat it. Quote its condition with every strength figure. No density or quenched-and-tempered strength value was found for it.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Other names and standards
The same grade under other systems, as datasheets and standards print them. Each code was checked against the page it comes from.
| System | Codes |
|---|---|
| UNS | G10450 |
| EN | 1.0503 (nearest equivalent) |
| EN name | C45 (nearest equivalent) |
| AISI | 1045 |
| SAE | 1045 |
| JIS | S45C |
| ASTM | A29 (listed for AISI 1045 by MaterialWelding), A576 (listed for AISI 1045 by MaterialWelding) |
| ASME | SA-29 (grade 1045) |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | yield strength | Mechanical Properties (reference) table, Cold Drawn column, size under 16 mm, Yield Strength row printed as Min 540, value as printed | processing cold drawnsize under 16 mmtemperature not statedbasis minimum (datasheet Min) | — |
| 2 | ultimate tensile strength | Mechanical Properties (reference) table, Cold Drawn column, size under 16 mm, Tensile Strength row printed as Min 690, value as printed | processing cold drawnsize under 16 mmtemperature not statedbasis minimum (datasheet Min) | — |
| 3 | elongation | Mechanical Properties (reference) table, Cold Drawn column, size under 16 mm, Elongation (A5 %) row printed as Min 8, value as printed | processing cold drawnsize under 16 mmgauge A5temperature not statedbasis minimum (datasheet Min) | — |
| 4 | yield strength | Mechanical Properties (reference) table, Cold Drawn column, size 16 to 38 mm, Yield Strength row printed as Min 510, value as printed | processing cold drawnsize 16 to 38 mmtemperature not statedbasis minimum (datasheet Min) | — |
| 5 | ultimate tensile strength | Mechanical Properties (reference) table, Cold Drawn column, size 16 to 38 mm, Tensile Strength row printed as Min 650, value as printed | processing cold drawnsize 16 to 38 mmtemperature not statedbasis minimum (datasheet Min) | — |
| 6 | elongation | Mechanical Properties (reference) table, Cold Drawn column, size 16 to 38 mm, Elongation (A5 %) row printed as Min 8, value as printed | processing cold drawnsize 16 to 38 mmgauge A5temperature not statedbasis minimum (datasheet Min) | — |
| 7 | yield strength | Mechanical Properties (reference) table, Cold Drawn column, size 38 to 63 mm, Yield Strength row printed as Min 500, value as printed | processing cold drawnsize 38 to 63 mmtemperature not statedbasis minimum (datasheet Min) | — |
| 8 | ultimate tensile strength | Mechanical Properties (reference) table, Cold Drawn column, size 38 to 63 mm, Tensile Strength row printed as Min 640, value as printed | processing cold drawnsize 38 to 63 mmtemperature not statedbasis minimum (datasheet Min) | — |
| 9 | elongation | Mechanical Properties (reference) table, Cold Drawn column, size 38 to 63 mm, Elongation (A5 %) row printed as Min 9, value as printed | processing cold drawnsize 38 to 63 mmgauge A5temperature not statedbasis minimum (datasheet Min) | — |
| 10 | yield strength | Mechanical Properties (reference) table, column headed Rolled (the same page lists Hot Rolled as a supply condition), size under 250 mm, Yield Strength row printed as Min 300, value as printed | processing hot rolledsize under 250 mmtemperature not statedbasis minimum (datasheet Min) | — |
| 11 | ultimate tensile strength | Mechanical Properties (reference) table, column headed Rolled (the same page lists Hot Rolled as a supply condition), Tensile Strength row printed as 570-700, range as printed | processing hot rolledsize under 250 mmtemperature not statedbasis range as printed | — |
| 12 | elongation | Mechanical Properties (reference) table, column headed Rolled, size under 250 mm, Elongation (A5 %) row printed as Min 14, value as printed | processing hot rolledsize under 250 mmgauge A5temperature not statedbasis minimum (datasheet Min) | — |
| 13 | brinell hardness | Mechanical Properties (reference) table, column headed Rolled, Hardness (HB) row printed as 170-210, range as printed; custom name brinell_hardness | processing hot rolledsize under 250 mmtemperature not statedbasis range as printed | — |
| 14 | yield strength | Typical Mechanical Properties table, As Rolled column, Yield Point (PSI) row, value as printed in psi | processing as rolled (hot rolled bar)product bar (page section C1045 Bar Products)temperature not statedbasis typical, representative tests | — |
| 15 | ultimate tensile strength | Typical Mechanical Properties table, As Rolled column, Tensile Strength (PSI) row, value as printed in psi | processing as rolled (hot rolled bar)product bar (page section C1045 Bar Products)temperature not statedbasis typical, representative tests | — |
| 16 | elongation | Typical Mechanical Properties table, As Rolled column, Elongation row, percent in 2 in as printed in the table footnote | processing as rolled (hot rolled bar)product bar (page section C1045 Bar Products)gauge 2 intemperature not statedbasis typical, representative tests | — |
| 17 | yield strength | Typical Mechanical Properties table, Normalized column, Yield Point (PSI) row, value as printed in psi | processing normalizedproduct bar (page section C1045 Bar Products)temperature not statedbasis typical, representative tests | — |
| 18 | ultimate tensile strength | Typical Mechanical Properties table, Normalized column, Tensile Strength (PSI) row, value as printed in psi | processing normalizedproduct bar (page section C1045 Bar Products)temperature not statedbasis typical, representative tests | — |
| 19 | elongation | Typical Mechanical Properties table, Normalized column, Elongation row, percent in 2 in as printed in the table footnote | processing normalizedproduct bar (page section C1045 Bar Products)gauge 2 intemperature not statedbasis typical, representative tests | — |
| 20 | yield strength | Typical Mechanical Properties table, Annealed column, Yield Point (PSI) row, value as printed in psi | processing annealedproduct bar (page section C1045 Bar Products)temperature not statedbasis typical, representative tests | — |
| 21 | ultimate tensile strength | Typical Mechanical Properties table, Annealed column, Tensile Strength (PSI) row, value as printed in psi | processing annealedproduct bar (page section C1045 Bar Products)temperature not statedbasis typical, representative tests | — |
| 22 | elongation | Typical Mechanical Properties table, Annealed column, Elongation row, percent in 2 in as printed in the table footnote | processing annealedproduct bar (page section C1045 Bar Products)gauge 2 intemperature not statedbasis typical, representative tests | — |
| 23 | elastic modulus | AISI 1045 Physical Properties table, Modulus of Elasticity row, range printed as 190 to 210 with unit GPa; the temperature tab for this value is not identified in the extracted text | processing not statedtemperature not stated on the extracted pagebasis range as printed | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Moist air, with or without salt | not rated | Carbon steel rusts in moist air, and salt makes it worse1 |
| Seawater and salt spray | not rated | Salt makes iron rust faster2 |
| Moisture in air (rust as iron oxide) | not rated | Rust is an iron oxide that forms from iron, oxygen and water or air moisture3 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Moist air, with or without salt | Per Wikipedia, carbon steel is susceptible to rust and corrosion, especially in environments with high moisture levels and/or salt. It can be shielded from corrosion by coating it with paint, varnish or other protective material. No corrosion rate for AISI 1045 was found. | humidity high moisturesalt adds to the attack |
| 2 | Seawater and salt spray | Per Wikipedia, if salt is present, for example in seawater or salt spray, iron tends to rust more quickly, as a result of chemical reactions. | exposure seawater or salt spray |
| 3 | Moisture in air (rust as iron oxide) | Per Wikipedia, rust is a usually reddish-brown iron oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Surface rust is flaky and gives no passivational protection to the iron underneath. | humidity water or air moisture |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The PubChem records are for elemental manganese and iron, not for the solid steel. No AISI 1045 safety data sheet was found.
- Manganese
- PubChem lists elemental manganese as Danger, with H372 (damage to organs through prolonged or repeated exposure).
- Iron
- PubChem lists elemental iron with H228 (flammable solid) in some reports, and most reports do not meet GHS hazard criteria.
- Workshop
- Cutting, grinding and welding make metal dust and fume. Fume and dust limits were not found, so check the supplier safety data sheet before work.
In the environment
Rust is the main failure route for AISI 1045 outdoors.
- Moist air
- Carbon steel is susceptible to rust in environments with high moisture, and salt makes it worse (Wikipedia, Carbon steel).
- Coating
- Paint, varnish or another protective coating shields it (Wikipedia, Carbon steel).
Heat and welding
Quench hardening brings brittleness, and welding needs preheat.
- Quench
- Heating to about 850 °C and quenching in water or oil raises hardness but reduces malleability and increases brittleness (Wikipedia, Carbon steel).
- Welding
- Preheat to about 200 to 300 °C to avoid cracking, because of its high carbon content (MaterialWelding).
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Atmospheric rust on uncoated surfaces | Moist air, or salt in seawater or salt sprayRust forms and is faster with salt; surface rust is flaky and gives no passivational protection to the iron underneath (Wikipedia, Rust) |
| Cracking during welding | High carbon content with no preheatCracks in the weld zone unless the part is preheated to about 200 to 300 °C (MaterialWelding) |
| Brittleness after quench hardening | Heating to about 850 °C, then rapid quenching in water or oilHardness and tensile strength rise, but malleability falls and fractures become much more likely (Wikipedia, Carbon steel) |
Handling and storage
- Stress relieve cold-drawn bar at not less than 288 °C after drawing (Total Materia)
- Recommended heat treatment, voestalpine: normalise at 850 °C and air cool; anneal at 680 to 710 °C and cool slowly in a controlled furnace; harden at 800 to 830 °C and water quench; temper at 150 to 200 °C and air cool
- Total Materia gives hardening at 815 to 845 °C with a quench in water or caustic
- Preheat to about 200 to 300 °C before welding to avoid cracking; post-weld heat treatment at 550 to 660 °C, kept below the tempering temperature of quenched and tempered parts (MaterialWelding)
- Machine in the normalised condition, which MaterialWelding prefers; annealed machining is also possible
Mitigations
- Coat it with paint, varnish or another protective material (Wikipedia, Carbon steel)
- Use a stainless alloy with chromium where corrosion resistance is essential (Wikipedia, Carbon steel)
- Keep parts dry and out of salt spray, because salt makes rust faster (Wikipedia, Rust)
Supply and geography
How common the raw materials are and where they come from.
Iron and steel (United States)
Iron is the least expensive and most widely used metal (USGS). The US produced 82 million metric tons of raw steel in 2025 and its net import reliance was 13 percent of apparent consumption in 2025e. Construction took an estimated 31 percent of net shipments.
- Recycling
- Scrap recycling is covered in the separate USGS Iron and Steel Scrap chapter, which was not checked for this profile
- Substitutes
- Aluminum and plastics in the automotive industry; aluminum, concrete and wood in construction (USGS Substitutes text)
Raw steel production by country (2025e)
World raw steel production was 1,900 million metric tons in 2025e (rounded total). Printed 2025e raw steel tonnages in million metric tons: China 980, India 160, United States 82, Japan 81, Russia 65.
- Top producers (2025)
- China, India, United States, Japan, Russia
Manganese (United States)
No manganese ore containing 20 percent or more manganese has been produced in the United States since 1970 (USGS). Net import reliance was 100 percent of apparent consumption in 2025e (manganese content). Manganese content typically ranges from 35 to 54 percent in ore and from 74 to 95 percent in ferromanganese.
- Recycling
- Manganese is recovered along with iron from steel slag, but recovery specifically for manganese was negligible (USGS)
Manganese ore and ferromanganese import sources (2021 to 2024)
Manganese ore: Gabon 64 percent, South Africa 24 percent, Mexico 12 percent, other under 1 percent. Ferromanganese: Malaysia 26 percent, Australia 16 percent, Norway 16 percent, South Africa 14 percent, other 28 percent (USGS).
Manganese ore production and resources (world)
Mine production in 2025e, manganese content, thousand metric tons: South Africa 7,600, Gabon 5,000, Ghana 2,000, Australia 1,600, China 700; world total 20,000 (rounded). South Africa holds an estimated 70 percent of world manganese resources (USGS).
- Top producers (2025)
- South Africa, Gabon, Ghana, Australia, China
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
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spore: profile
id: steel-1045
spore_version: 0.2
family: carbon-and-alloy-steels
name: Carbon steel 1045
abbreviation: 1045 (UNS G10450, AISI 1045)
role: medium-carbon machinery steel
category: metals
type: steels-and-stainless
summary: |
AISI 1045 is a plain medium-carbon steel: iron with about 0.43 to 0.50 percent carbon and 0.60 to 0.90 percent manganese. It is stronger than low-carbon steel, especially after heat treatment, and it is used for axles, shafts, gears and machine parts. It rusts in moist air and salt, so outdoor parts need a coating, and its strength depends on the processing condition.
best_for: Forged or machined axles, shafts, gears and machine parts that need more strength than low-carbon steel, and that are coated against rust
weakest_at: Rust in moist air and salt unless it is coated, and strength that depends on whether the bar was cold drawn, hot rolled, normalised or annealed
identity:
formula: Fe balance; 0.43 to 0.50 C, 0.60 to 0.90 Mn, max 0.040 P, max 0.050 S, max 0.100 Si (wt%)
source: icast-aisi1045
where: Chemical Composition table, AISI 1045 sheet
designations:
- system: UNS
code: G10450
source: icast-aisi1045
where: Cross Reference Table, row G10450 (UNS)
- system: AISI
code: '1045'
source: icast-aisi1045
where: 'Sheet title, Material: AISI 1045'
- system: SAE
code: '1045'
source: icast-sae1045
where: 'Sheet title, Material: SAE 1045'
- system: EN
code: '1.0503'
note: nearest equivalent
source: saarstahl-c45
where: Material No. field of the Saarstahl C45 sheet
- system: EN name
code: C45
note: nearest equivalent
source: saarstahl-c45
where: Sheet title Saarstahl - C45
- system: JIS
code: S45C
source: totalmateria-1045
where: International Equivalent Materials list, row S45C (JIS, Japan, Official)
- system: ASTM
code: A29
note: listed for AISI 1045 by MaterialWelding
source: materialwelding-1045
where: Material Specification standards for AISI 1045 Steel list
- system: ASTM
code: A576
note: listed for AISI 1045 by MaterialWelding
source: materialwelding-1045
where: Material Specification standards for AISI 1045 Steel list
- system: ASME
code: SA-29
note: grade 1045
source: totalmateria-1045
where: International Equivalent Materials list, row SA-29 1045 (ASME)
tags:
environments: []
stresses: []
applications:
- mechanisms
- structures
properties:
- benchmark: yield_strength
value: 540
bound: lower
unit: MPa
scope: material
conditions:
processing: cold drawn
size: under 16 mm
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, Cold Drawn column, size under 16 mm, Yield Strength row printed as Min 540, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Cold Drawn, size under 16 mm, Yield Strength row
- benchmark: ultimate_tensile_strength
value: 690
bound: lower
unit: MPa
scope: material
conditions:
processing: cold drawn
size: under 16 mm
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, Cold Drawn column, size under 16 mm, Tensile Strength row printed as Min 690, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Cold Drawn, size under 16 mm, Tensile Strength row
- benchmark: elongation
value: 8
bound: lower
unit: '%'
scope: material
conditions:
processing: cold drawn
size: under 16 mm
gauge: A5
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, Cold Drawn column, size under 16 mm, Elongation (A5 %) row printed as Min 8, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Cold Drawn, size under 16 mm, Elongation row
- benchmark: yield_strength
value: 510
bound: lower
unit: MPa
scope: material
conditions:
processing: cold drawn
size: 16 to 38 mm
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, Cold Drawn column, size 16 to 38 mm, Yield Strength row printed as Min 510, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Cold Drawn, size 16 to 38 mm, Yield Strength row
- benchmark: ultimate_tensile_strength
value: 650
bound: lower
unit: MPa
scope: material
conditions:
processing: cold drawn
size: 16 to 38 mm
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, Cold Drawn column, size 16 to 38 mm, Tensile Strength row printed as Min 650, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Cold Drawn, size 16 to 38 mm, Tensile Strength row
- benchmark: elongation
value: 8
bound: lower
unit: '%'
scope: material
conditions:
processing: cold drawn
size: 16 to 38 mm
gauge: A5
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, Cold Drawn column, size 16 to 38 mm, Elongation (A5 %) row printed as Min 8, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Cold Drawn, size 16 to 38 mm, Elongation row
- benchmark: yield_strength
value: 500
bound: lower
unit: MPa
scope: material
conditions:
processing: cold drawn
size: 38 to 63 mm
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, Cold Drawn column, size 38 to 63 mm, Yield Strength row printed as Min 500, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Cold Drawn, size 38 to 63 mm, Yield Strength row
- benchmark: ultimate_tensile_strength
value: 640
bound: lower
unit: MPa
scope: material
conditions:
processing: cold drawn
size: 38 to 63 mm
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, Cold Drawn column, size 38 to 63 mm, Tensile Strength row printed as Min 640, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Cold Drawn, size 38 to 63 mm, Tensile Strength row
- benchmark: elongation
value: 9
bound: lower
unit: '%'
scope: material
conditions:
processing: cold drawn
size: 38 to 63 mm
gauge: A5
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, Cold Drawn column, size 38 to 63 mm, Elongation (A5 %) row printed as Min 9, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Cold Drawn, size 38 to 63 mm, Elongation row
- benchmark: yield_strength
value: 300
bound: lower
unit: MPa
scope: material
conditions:
processing: hot rolled
size: under 250 mm
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, column headed Rolled (the same page lists Hot Rolled as a supply condition), size under 250 mm, Yield Strength row printed as Min 300, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Rolled column, Yield Strength row
- benchmark: ultimate_tensile_strength
value: 570
value_high: 700
bound: range
unit: MPa
scope: material
conditions:
processing: hot rolled
size: under 250 mm
temperature: not stated
basis: range as printed
method: Mechanical Properties (reference) table, column headed Rolled (the same page lists Hot Rolled as a supply condition), Tensile Strength row printed as 570-700, range as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Rolled column, Tensile Strength row
- benchmark: elongation
value: 14
bound: lower
unit: '%'
scope: material
conditions:
processing: hot rolled
size: under 250 mm
gauge: A5
temperature: not stated
basis: minimum (datasheet Min)
method: Mechanical Properties (reference) table, column headed Rolled, size under 250 mm, Elongation (A5 %) row printed as Min 14, value as printed
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Rolled column, Elongation row
- benchmark: brinell_hardness
value: 170
value_high: 210
bound: range
unit: HB
scope: material
conditions:
processing: hot rolled
size: under 250 mm
temperature: not stated
basis: range as printed
method: Mechanical Properties (reference) table, column headed Rolled, Hardness (HB) row printed as 170-210, range as printed; custom name brinell_hardness
status: ground
source: voestalpine-1045
where: Mechanical Properties (reference) table, Rolled column, Hardness row
- benchmark: yield_strength
value: 59000
unit: psi
scope: material
conditions:
processing: as rolled (hot rolled bar)
product: bar (page section C1045 Bar Products)
temperature: not stated
basis: typical, representative tests
method: Typical Mechanical Properties table, As Rolled column, Yield Point (PSI) row, value as printed in psi
status: ground
source: metalsupermarkets-1045
where: Typical Mechanical Properties table, As Rolled column, Yield Point row
- benchmark: ultimate_tensile_strength
value: 90000
unit: psi
scope: material
conditions:
processing: as rolled (hot rolled bar)
product: bar (page section C1045 Bar Products)
temperature: not stated
basis: typical, representative tests
method: Typical Mechanical Properties table, As Rolled column, Tensile Strength (PSI) row, value as printed in psi
status: ground
source: metalsupermarkets-1045
where: Typical Mechanical Properties table, As Rolled column, Tensile Strength row
- benchmark: elongation
value: 26
unit: '%'
scope: material
conditions:
processing: as rolled (hot rolled bar)
product: bar (page section C1045 Bar Products)
gauge: 2 in
temperature: not stated
basis: typical, representative tests
method: Typical Mechanical Properties table, As Rolled column, Elongation row, percent in 2 in as printed in the table footnote
status: ground
source: metalsupermarkets-1045
where: Typical Mechanical Properties table, As Rolled column, Elongation row
- benchmark: yield_strength
value: 58000
unit: psi
scope: material
conditions:
processing: normalized
product: bar (page section C1045 Bar Products)
temperature: not stated
basis: typical, representative tests
method: Typical Mechanical Properties table, Normalized column, Yield Point (PSI) row, value as printed in psi
status: ground
source: metalsupermarkets-1045
where: Typical Mechanical Properties table, Normalized column, Yield Point row
- benchmark: ultimate_tensile_strength
value: 87000
unit: psi
scope: material
conditions:
processing: normalized
product: bar (page section C1045 Bar Products)
temperature: not stated
basis: typical, representative tests
method: Typical Mechanical Properties table, Normalized column, Tensile Strength (PSI) row, value as printed in psi
status: ground
source: metalsupermarkets-1045
where: Typical Mechanical Properties table, Normalized column, Tensile Strength row
- benchmark: elongation
value: 28
unit: '%'
scope: material
conditions:
processing: normalized
product: bar (page section C1045 Bar Products)
gauge: 2 in
temperature: not stated
basis: typical, representative tests
method: Typical Mechanical Properties table, Normalized column, Elongation row, percent in 2 in as printed in the table footnote
status: ground
source: metalsupermarkets-1045
where: Typical Mechanical Properties table, Normalized column, Elongation row
- benchmark: yield_strength
value: 48000
unit: psi
scope: material
conditions:
processing: annealed
product: bar (page section C1045 Bar Products)
temperature: not stated
basis: typical, representative tests
method: Typical Mechanical Properties table, Annealed column, Yield Point (PSI) row, value as printed in psi
status: ground
source: metalsupermarkets-1045
where: Typical Mechanical Properties table, Annealed column, Yield Point row
- benchmark: ultimate_tensile_strength
value: 80000
unit: psi
scope: material
conditions:
processing: annealed
product: bar (page section C1045 Bar Products)
temperature: not stated
basis: typical, representative tests
method: Typical Mechanical Properties table, Annealed column, Tensile Strength (PSI) row, value as printed in psi
status: ground
source: metalsupermarkets-1045
where: Typical Mechanical Properties table, Annealed column, Tensile Strength row
- benchmark: elongation
value: 30
unit: '%'
scope: material
conditions:
processing: annealed
product: bar (page section C1045 Bar Products)
gauge: 2 in
temperature: not stated
basis: typical, representative tests
method: Typical Mechanical Properties table, Annealed column, Elongation row, percent in 2 in as printed in the table footnote
status: ground
source: metalsupermarkets-1045
where: Typical Mechanical Properties table, Annealed column, Elongation row
- benchmark: elastic_modulus
value: 190
value_high: 210
bound: range
unit: GPa
scope: material
conditions:
processing: not stated
temperature: not stated on the extracted page
basis: range as printed
method: AISI 1045 Physical Properties table, Modulus of Elasticity row, range printed as 190 to 210 with unit GPa; the temperature tab for this value is not identified in the extracted text
status: ground
source: totalmateria-1045
where: AISI 1045 Physical Properties table, Modulus of Elasticity row
corrosion:
- environment: Moist air, with or without salt
headline: Carbon steel rusts in moist air, and salt makes it worse
effect: Per Wikipedia, carbon steel is susceptible to rust and corrosion, especially in environments with high moisture levels and/or salt. It can be shielded from corrosion by coating it with paint, varnish or other protective material. No corrosion rate for AISI 1045 was found.
rating: unknown
conditions:
humidity: high moisture
salt: adds to the attack
source: wiki-carbon-steel
where: Corrosion paragraph
- environment: Seawater and salt spray
headline: Salt makes iron rust faster
effect: Per Wikipedia, if salt is present, for example in seawater or salt spray, iron tends to rust more quickly, as a result of chemical reactions.
rating: unknown
conditions:
exposure: seawater or salt spray
source: wiki-rust
where: Rust article, paragraph on salt
- environment: Moisture in air (rust as iron oxide)
headline: Rust is an iron oxide that forms from iron, oxygen and water or air moisture
effect: Per Wikipedia, rust is a usually reddish-brown iron oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Surface rust is flaky and gives no passivational protection to the iron underneath.
rating: unknown
conditions:
humidity: water or air moisture
source: wiki-rust
where: Lead paragraph and surface rust paragraph
risks:
hazards:
- text: 'PubChem aggregated GHS for elemental manganese, signal word Danger: H372 causes damage to organs through prolonged or repeated exposure; H228 (11.6%) flammable solid. PubChem notes that the element does not meet GHS hazard criteria for 46.1% (1429 of 3101) of reports. It covers the metal, not the solid steel.'
ghs:
- H372
- H228
source: pubchem-mn
where: Safety and Hazards, GHS Classification
- text: 'PubChem aggregated GHS for elemental iron, signal word Danger: H228 (15.5%) flammable solid. PubChem notes that the element does not meet GHS hazard criteria for 74.1% (4458 of 6013) of reports. It covers the metal, not the solid steel.'
ghs:
- H228
source: pubchem-fe
where: Safety and Hazards, GHS Classification
failure_risks:
- mode: Atmospheric rust on uncoated surfaces
trigger: Moist air, or salt in seawater or salt spray
consequence: Rust forms and is faster with salt; surface rust is flaky and gives no passivational protection to the iron underneath (Wikipedia, Rust)
source: wiki-rust
where: Lead paragraph, salt paragraph and surface rust paragraph
- mode: Cracking during welding
trigger: High carbon content with no preheat
consequence: Cracks in the weld zone unless the part is preheated to about 200 to 300 °C (MaterialWelding)
source: materialwelding-1045
where: AISI 1045 Welding section
- mode: Brittleness after quench hardening
trigger: Heating to about 850 °C, then rapid quenching in water or oil
consequence: Hardness and tensile strength rise, but malleability falls and fractures become much more likely (Wikipedia, Carbon steel)
source: wiki-carbon-steel
where: Heat treatment paragraph
side_effects: []
handling:
- text: Stress relieve cold-drawn bar at not less than 288 °C after drawing (Total Materia)
source: totalmateria-1045
where: AISI 1045 Heat Treatments
- text: 'Recommended heat treatment, voestalpine: normalise at 850 °C and air cool; anneal at 680 to 710 °C and cool slowly in a controlled furnace; harden at 800 to 830 °C and water quench; temper at 150 to 200 °C and air cool'
source: voestalpine-1045
where: Heat Treatment (recommended) table
- text: Total Materia gives hardening at 815 to 845 °C with a quench in water or caustic
source: totalmateria-1045
where: AISI 1045 Heat Treatments
- text: Preheat to about 200 to 300 °C before welding to avoid cracking; post-weld heat treatment at 550 to 660 °C, kept below the tempering temperature of quenched and tempered parts (MaterialWelding)
source: materialwelding-1045
where: AISI 1045 Welding section
- text: Machine in the normalised condition, which MaterialWelding prefers; annealed machining is also possible
source: materialwelding-1045
where: AISI 1045 Machining section
mitigations:
- text: Coat it with paint, varnish or another protective material (Wikipedia, Carbon steel)
source: wiki-carbon-steel
where: Corrosion paragraph
- text: Use a stainless alloy with chromium where corrosion resistance is essential (Wikipedia, Carbon steel)
source: wiki-carbon-steel
where: Corrosion paragraph
- text: Keep parts dry and out of salt spray, because salt makes rust faster (Wikipedia, Rust)
source: wiki-rust
where: Salt paragraph
uses:
- application: mechanisms
device: Axles, clutch members and shafts
example: Heavy forgings in the normalised condition are suitable for automotive and general engineering, such as axles, clutch members and shafts (voestalpine)
source: voestalpine-1045
where: Description paragraph
- application: mechanisms
device: Gears, pinions and stud bolts
example: Metal Supermarkets lists axles, stud bolts, ordinary shafts, pinions and gears as typical applications
source: metalsupermarkets-1045
where: Typical Applications list
- application: structures
device: Heavy machinery parts
example: MaterialWelding lists heavy machinery such as drilling rigs, oil rigs and mining equipment among its uses
source: materialwelding-1045
where: AISI 1045 Steel Applications list
supply:
- subject: Iron and steel (United States)
abundance: Iron is the least expensive and most widely used metal (USGS). The US produced 82 million metric tons of raw steel in 2025 and its net import reliance was 13 percent of apparent consumption in 2025e. Construction took an estimated 31 percent of net shipments.
producers: []
critical_lists: []
recycling: Scrap recycling is covered in the separate USGS Iron and Steel Scrap chapter, which was not checked for this profile
substitutes:
- Aluminum and plastics in the automotive industry; aluminum, concrete and wood in construction (USGS Substitutes text)
source: usgs-iron-steel-2026
where: Domestic Production and Use; Salient Statistics table; Substitutes
- subject: Raw steel production by country (2025e)
abundance: 'World raw steel production was 1,900 million metric tons in 2025e (rounded total). Printed 2025e raw steel tonnages in million metric tons: China 980, India 160, United States 82, Japan 81, Russia 65.'
producers:
- country: China
year: 2025
- country: India
year: 2025
- country: United States
year: 2025
- country: Japan
year: 2025
- country: Russia
year: 2025
critical_lists: []
recycling: ''
substitutes: []
source: usgs-iron-steel-2026
where: World Production table, Raw steel 2025e column
- subject: Manganese (United States)
abundance: No manganese ore containing 20 percent or more manganese has been produced in the United States since 1970 (USGS). Net import reliance was 100 percent of apparent consumption in 2025e (manganese content). Manganese content typically ranges from 35 to 54 percent in ore and from 74 to 95 percent in ferromanganese.
producers: []
critical_lists: []
recycling: Manganese is recovered along with iron from steel slag, but recovery specifically for manganese was negligible (USGS)
substitutes: []
source: usgs-manganese-2026
where: Domestic Production and Use; Salient Statistics table, net import reliance row
- subject: Manganese ore and ferromanganese import sources (2021 to 2024)
abundance: 'Manganese ore: Gabon 64 percent, South Africa 24 percent, Mexico 12 percent, other under 1 percent. Ferromanganese: Malaysia 26 percent, Australia 16 percent, Norway 16 percent, South Africa 14 percent, other 28 percent (USGS).'
producers: []
critical_lists: []
substitutes: []
source: usgs-manganese-2026
where: Import Sources (2021 to 2024)
- subject: Manganese ore production and resources (world)
abundance: 'Mine production in 2025e, manganese content, thousand metric tons: South Africa 7,600, Gabon 5,000, Ghana 2,000, Australia 1,600, China 700; world total 20,000 (rounded). South Africa holds an estimated 70 percent of world manganese resources (USGS).'
producers:
- country: South Africa
year: 2025
- country: Gabon
year: 2025
- country: Ghana
year: 2025
- country: Australia
year: 2025
- country: China
year: 2025
critical_lists: []
substitutes: []
source: usgs-manganese-2026
where: World Mine Production (manganese content) and Reserves table, 2025e column; World Resources paragraph
media: []
documents:
- title: 'voestalpine High Performance Metals: AISI 1045 / 1.1191 / G10430 datasheet (Australia)'
type: datasheet
url: https://www.voestalpine.com/highperformancemetals/australia/app/uploads/sites/265/2024/08/Datasheet-1045-2026-v1.pdf
- title: 'Metal Supermarkets: Hot Rolled Steel C1045 grade summary'
type: datasheet
url: https://www.metalsupermarkets.com/hot-rolled-steel-c1045/
- title: 'iCAST Alloys: AISI 1045 carbon steel composition and cross-reference sheet'
type: datasheet
url: https://icastllp.com/material_db_pdf/AISI%201045.pdf
- title: 'iCAST Alloys: SAE 1045 carbon steel composition and cross-reference sheet'
type: datasheet
url: https://icastllp.com/material_db_pdf/SAE%201045.pdf
- title: 'Saarstahl: Material specification sheet, C45 (1.0503)'
type: datasheet
url: https://en.saarstahl.com/app/uploads/2024/03/20160401102929-0503_C45.pdf
- title: 'Total Materia: AISI 1045 Structural and constructional steels'
type: database
url: https://www.totalmateria.com/en-us/material/1250033
- title: 'MaterialWelding.com: AISI 1045 Steel S45C C45 Properties'
type: report
url: https://materialwelding.com/?p=524362
- title: 'USGS Mineral Commodity Summaries 2026: Iron and Steel'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-iron-steel.pdf
year: 2026
- title: 'USGS Mineral Commodity Summaries 2026: Manganese'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-manganese.pdf
year: 2026
- title: 'PubChem: Manganese (CID 23930), GHS classification'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23930/JSON
- title: 'PubChem: Iron (CID 23925), GHS classification'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23925/JSON
gaps:
- Density, Poisson's ratio, shear modulus, specific heat, thermal conductivity, coefficient of thermal expansion, electrical resistivity and melting range for AISI 1045 were not found on any page fetched. Total Materia shows these only as locked values (val1, free registration).
- No quenched-and-tempered strength or hardness value for AISI 1045 was found. Voestalpine gives tempering at 150 to 200 °C, Total Materia gives hardening at 815 to 845 °C, and MaterialWelding gives a tempering range of 400 to 640 °C with no strength figures. The Saarstahl sheet has quenched-and-tempered values, but it is for C45 (1.0503), so it is not used.
- Normalised and annealed values are typical figures from Metal Supermarkets, a reseller, in psi as printed. No manufacturer minimum for normalised or annealed bar was found. The voestalpine column for forgings, rough machined and normalised product over 250 mm mixes conditions, so it is not used.
- Voestalpine cold-drawn and hot-rolled figures are minimum reference limits (Min), not typical values. Its hot-rolled column is headed Rolled; the page lists Hot Rolled as a supply condition, which is why the column is recorded as hot rolled.
- Hardness is recorded under the custom name brinell_hardness, which is not in property-canon. Metal Supermarkets prints Brinell values of 201, 192 and 159 with no unit, so they are not recorded, and its plate figures are not recorded because the plate condition is not stated.
- Total Materia's tensile range of 450 to 862 MPa has no condition and is not recorded. The iCAST AISI 1045 and SAE 1045 mechanical blocks give ranges and minimums for several conditions together, so they are not recorded. MaterialWelding's general mechanical values (81.9 ksi, 45 ksi, 163 HB) have no condition and are not recorded.
- Composition limits differ between sources. Voestalpine prints maximum sulfur and phosphorus of 0.035 and silicon of 0.35; MaterialWelding prints silicon 0.15 to 0.35; the iCAST SAE 1045 sheet prints phosphorus 0.030 maximum and lead 0.150 to 0.350. The recipe uses the iCAST AISI 1045 sheet, which matches Metal Supermarkets for carbon, manganese, phosphorus and sulfur.
- No ASTM A108 designation is listed, because no page fetched prints A108 for this grade. ASTM cross-references printed by iCAST and Total Materia (A 311 Class A and B, A 827, A 682 and A 830) are not listed, and the voestalpine nearest-standards column (1.1191 CK45, 1.0501 C45) and its G10430 header are not listed.
- EN 1.0503 and C45 carry the note nearest equivalent. Saarstahl lists SAE 1045 among the international grades of 1.0503, but its manganese range (0.50 to 0.80) differs from the 0.60 to 0.90 printed for AISI 1045.
- No corrosion rate, salt-spray result or atmospheric test for AISI 1045 was found. The corrosion entries are qualitative and come from Wikipedia. Xometry returned 403, a guessed MISUMI blog URL returned a 404 page, and the Kippwerk page was empty.
- The USGS iron and steel chapter was read; the iron ore and scrap chapters were not. No critical-mineral listing was found in the manganese chapter text, so critical_lists is empty for the supply items.
- The PubChem hazard records cover elemental manganese and iron, not solid steel. No AISI 1045 safety data sheet was found, and welding fume and dust limits were not found. Stress, fatigue, impact, fire and high-temperature strength were not found for AISI 1045.
- The Total Materia modulus value is not tied to one of its temperature tabs in the extracted text, so its temperature is recorded as not stated.
sources:
voestalpine-1045:
title: 'voestalpine High Performance Metals: AISI 1045 / 1.1191 / G10430 datasheet (Australia)'
url: https://www.voestalpine.com/highperformancemetals/australia/app/uploads/sites/265/2024/08/Datasheet-1045-2026-v1.pdf
kind: datasheet
license: cited, not reproduced
metalsupermarkets-1045:
title: 'Metal Supermarkets: Hot Rolled Steel C1045 grade summary'
url: https://www.metalsupermarkets.com/hot-rolled-steel-c1045/
kind: web
license: cited, not reproduced
icast-aisi1045:
title: 'iCAST Alloys: AISI 1045 carbon steel composition and cross-reference sheet'
url: https://icastllp.com/material_db_pdf/AISI%201045.pdf
kind: datasheet
license: cited, not reproduced
icast-sae1045:
title: 'iCAST Alloys: SAE 1045 carbon steel composition and cross-reference sheet'
url: https://icastllp.com/material_db_pdf/SAE%201045.pdf
kind: datasheet
license: cited, not reproduced
saarstahl-c45:
title: 'Saarstahl: Material specification sheet, C45 (1.0503)'
url: https://en.saarstahl.com/app/uploads/2024/03/20160401102929-0503_C45.pdf
kind: datasheet
license: cited, not reproduced
totalmateria-1045:
title: 'Total Materia: AISI 1045 Structural and constructional steels'
url: https://www.totalmateria.com/en-us/material/1250033
kind: database
license: cited, not reproduced
materialwelding-1045:
title: 'MaterialWelding.com: AISI 1045 Steel S45C C45 Properties'
url: https://materialwelding.com/?p=524362
kind: web
license: cited, not reproduced
usgs-iron-steel-2026:
title: 'USGS Mineral Commodity Summaries 2026: Iron and Steel'
id: mcs2026-iron-steel
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-iron-steel.pdf
kind: report
year: 2026
license: public domain
usgs-manganese-2026:
title: 'USGS Mineral Commodity Summaries 2026: Manganese'
id: mcs2026-manganese
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-manganese.pdf
kind: report
year: 2026
license: public domain
wiki-carbon-steel:
title: 'Wikipedia: Carbon steel'
id: Carbon steel
url: https://en.wikipedia.org/wiki/Carbon_steel
kind: web
license: CC BY-SA 4.0 (cited, not reproduced)
wiki-rust:
title: 'Wikipedia: Rust'
id: Rust
url: https://en.wikipedia.org/wiki/Rust
kind: web
license: CC BY-SA 4.0 (cited, not reproduced)
pubchem-mn:
title: 'PubChem: Manganese (CID 23930), Safety and Hazards, GHS Classification (REST record)'
id: CID 23930
url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23930/JSON
kind: database
license: PubChem terms (public)
pubchem-fe:
title: 'PubChem: Iron (CID 23925), Safety and Hazards, GHS Classification (REST record)'
id: CID 23925
url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23925/JSON
kind: database
license: PubChem terms (public)
license: CC-BY-4.0
updated: '2026-10-24'
review:
status: draft
method: assistant
checked_values: 23
unreachable: 0
caveats: 21
note: 'Read by an AI assistant on 2026-10-24 from pages fetched in that run. Strength rows are split by condition: cold drawn and hot rolled minimum limits from the voestalpine AISI 1045 datasheet (11 minimum values), typical as-rolled, normalised and annealed values from Metal Supermarkets, a reseller, in psi as printed (9 typical values), and an elastic modulus range from Total Materia with no condition stated (1 value).'
story:
why: AISI 1045 is the common medium-carbon steel. It is stronger than low-carbon steel and can be heat treated for more strength, so it is chosen for shafts, axles, gears and machine parts. Its strength depends on the condition the bar was made in, so every figure in this profile is kept with its own condition.
uses:
- where: Shafts, axles and clutch members
line: Voestalpine says heavy forgings in the normalised condition suit automotive and general engineering, such as axles, clutch members and shafts.
- where: Gears, pinions and stud bolts
line: Metal Supermarkets lists stud bolts, ordinary shafts, pinions and gears among its typical applications.
- where: Heavy machinery
line: MaterialWelding lists heavy machinery such as drilling rigs, oil rigs and mining equipment among the uses of AISI 1045.
can_do:
- label: Strength, cold drawn
benchmark: ultimate_tensile_strength
line: Cold-drawn bar under 16 mm has a minimum tensile strength of 690 MPa and a minimum yield strength of 540 MPa (voestalpine reference limits).
- label: Strength, hot rolled
benchmark: ultimate_tensile_strength
line: Hot-rolled bar under 250 mm has a tensile range of 570 to 700 MPa and a minimum yield strength of 300 MPa (voestalpine).
- label: Strength, as rolled
benchmark: yield_strength
line: Typical as-rolled bar gives 90000 psi tensile and 59000 psi yield (Metal Supermarkets, typical values).
- label: Strength, annealed
benchmark: yield_strength
line: Typical annealed bar gives 80000 psi tensile and 48000 psi yield (Metal Supermarkets, typical values).
- label: Stiffness
benchmark: elastic_modulus
line: Elastic modulus is 190 to 210 GPa, with no condition stated (Total Materia).
compare: 'AISI 1045 is a medium-carbon steel. Metal Supermarkets says heat treatment gives it more strength than lower-carbon steels can reach. Its figures depend on condition: the minimum yield for cold-drawn bar under 16 mm is 540 MPa, against 300 MPa for hot-rolled bar under 250 mm (voestalpine). Typical as-rolled and normalised bar give yield values of 59000 and 58000 psi (Metal Supermarkets). Every value here keeps its condition.'
compare_rows:
- label: Yield strength
benchmark: yield_strength
scope: material
- label: Ultimate tensile strength
benchmark: ultimate_tensile_strength
scope: material
- label: Elastic modulus
benchmark: elastic_modulus
scope: material
handling:
- 'Name the condition with every strength value: cold drawn, hot rolled, normalised and annealed give different figures (voestalpine, Metal Supermarkets).'
- Stress relieve cold-drawn bar at not less than 288 °C after drawing (Total Materia).
- Preheat before welding, and keep the post-weld heat treatment below the tempering temperature of quenched and tempered parts (MaterialWelding).
good_for:
- Forged or machined shafts, axles and gears that need more strength than low-carbon steel (voestalpine, Metal Supermarkets)
- Machine parts cut in the normalised condition, which MaterialWelding prefers for machining
watch_out:
- Moist air and salt cause rust, so paint or coat outdoor parts (Wikipedia, Carbon steel)
- 'Sources disagree on weldability: MaterialWelding says good weldability with preheat, while Metal Supermarkets says welding qualities are limited'
- Minimum limits (voestalpine) and typical values (Metal Supermarkets) are different kinds of figure, so they are kept apart
- Silicon and phosphorus limits differ between sources (see gaps); the recipe uses the iCAST AISI 1045 sheet
verdict: AISI 1045 is a strong, widely available medium-carbon steel for axles, shafts and gears. It rusts in moist air and salt, so coat it. Quote its condition with every strength figure. No density or quenched-and-tempered strength value was found for it.
recipe:
line: AISI 1045 is iron with 0.43 to 0.50 percent carbon and 0.60 to 0.90 percent manganese, with at most 0.040 percent phosphorus and 0.050 percent sulfur (iCAST AISI 1045 sheet). It is sold as hot-rolled or normalised bar, and also as cold-drawn bar (voestalpine, MaterialWelding).
parts:
- name: Iron
symbol: Fe
share_note: balance (the rest)
role: The matrix of the steel. Iron makes up the rest of the composition.
source: icast-aisi1045
where: Chemical Composition table, Iron row
- name: Carbon
symbol: C
share_percent: 0.43
share_high: 0.5
role: Sets the strength and hardness. Medium-carbon steel balances ductility and strength (Wikipedia, Carbon steel).
source: icast-aisi1045
where: Chemical Composition table, Carbon row
- name: Manganese
symbol: Mn
share_percent: 0.6
share_high: 0.9
role: Adds hardenability (Wikipedia, Carbon steel, describes manganese additions for hardenability).
source: icast-aisi1045
where: Chemical Composition table, Manganese row
- name: Phosphorus
symbol: P
share_note: max 0.040
role: Impurity held to a maximum limit.
source: icast-aisi1045
where: Chemical Composition table, Phosphorus row
- name: Sulfur
symbol: S
share_note: max 0.050
role: Impurity held low. Trace sulfur makes steel red-short, brittle and crumbly at high working temperatures (Wikipedia, Carbon steel).
source: icast-aisi1045
where: Chemical Composition table, Sulphur row
- name: Silicon
symbol: Si
share_note: max 0.100
role: Held to a maximum limit (iCAST). Other sources print a higher limit; see gaps.
source: icast-aisi1045
where: Chemical Composition table, Silicon row
risk_groups:
- title: For people
level: 1
verdict: PubChem hazards are for the metals
lead: The PubChem records are for elemental manganese and iron, not for the solid steel. No AISI 1045 safety data sheet was found.
points:
- label: Manganese
line: PubChem lists elemental manganese as Danger, with H372 (damage to organs through prolonged or repeated exposure).
- label: Iron
line: PubChem lists elemental iron with H228 (flammable solid) in some reports, and most reports do not meet GHS hazard criteria.
- label: Workshop
line: Cutting, grinding and welding make metal dust and fume. Fume and dust limits were not found, so check the supplier safety data sheet before work.
- title: In the environment
level: 2
verdict: Moisture and salt drive rust
lead: Rust is the main failure route for AISI 1045 outdoors.
points:
- label: Moist air
line: Carbon steel is susceptible to rust in environments with high moisture, and salt makes it worse (Wikipedia, Carbon steel).
- label: Coating
line: Paint, varnish or another protective coating shields it (Wikipedia, Carbon steel).
- title: Heat and welding
level: 1
verdict: Preheat and tempering matter
lead: Quench hardening brings brittleness, and welding needs preheat.
points:
- label: Quench
line: Heating to about 850 °C and quenching in water or oil raises hardness but reduces malleability and increases brittleness (Wikipedia, Carbon steel).
- label: Welding
line: Preheat to about 200 to 300 °C to avoid cracking, because of its high carbon content (MaterialWelding).
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.