Carbon steel 1018 1018 (UNS G10180, AISI 1018)

spore: profile
id: steel-1018
spore_version: 0.2
family: carbon-and-alloy-steels
name: Carbon steel 1018
abbreviation: 1018 (UNS G10180, AISI 1018)
role: low-carbon structural steel
category: metals
type: steels-and-stainless
summary: |
  AISI 1018 is a plain low-carbon steel: iron with about 0.14 to 0.20 percent carbon and 0.60 to 0.90 percent manganese. It is cheap, easy to machine and easy to weld, and it is sold as cold-drawn or hot-rolled bar. The cold-drawn bar has the higher yield strength of the two datasheets cited here. It rusts in moist air and salt, so outdoor parts are painted or coated.
best_for: Machined shafts, pins and gears, and cost-sensitive structural parts 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 or hot rolled
identity:
  formula: Fe balance; 0.14 to 0.20 C, 0.60 to 0.90 Mn, max 0.040 P, max 0.050 S (wt%)
  source: elgin-1018
  where: Component table (Weight %), Carbon Steel Grade 1018 datasheet
  designations:
    - system: UNS
      code: G10180
      source: elgin-1018
      where: Key Words line
    - system: AISI
      code: '1018'
      source: elgin-1018
      where: Title line, AISI 1018 Steel, cold drawn
    - system: SAE
      code: '1018'
      source: mwalloys-1018
      where: Equivalent grades table, AISI/SAE column (SAE/AISI 1018)
    - system: ASTM
      code: A108
      note: cold-drawn bars
      source: mwalloys-1018-plate
      where: Typical spec table, Cold-drawn bars row
    - system: ASTM
      code: A29
      note: bars (general reference)
      source: mwalloys-1018
      where: Standards and specs line (A29 general reference for bars)
    - system: ASTM
      code: A576
      note: forgings, as the page files it
      source: mwalloys-1018-plate
      where: Typical spec table, Forgings row
    - system: ASTM
      code: A519
      note: tubing (depending on product)
      source: mwalloys-1018-plate
      where: Typical spec table, Tubing / pipe row
    - system: AMS
      code: '5069'
      source: elgin-1018
      where: Key Words line
    - system: JIS
      code: S15C
      note: nearest equivalent
      source: mwalloys-1018-plate
      where: Closest equivalents list, Japan / JIS line
    - system: EN
      code: '1.0401'
      note: nearest equivalent
      source: mwalloys-1018-plate
      where: Closest equivalents list, Europe / EN / DIN line
    - system: EN name
      code: C15
      note: nearest equivalent
      source: mwalloys-1018-plate
      where: Closest equivalents list, Europe / EN / DIN line
    - system: EN
      code: '1.0453'
      source: elgin-1018
      where: Key Words line (DIN 1.0453)
    - system: DIN
      code: C16.8
      source: elgin-1018
      where: Key Words line (DIN C16.8)
tags:
  environments: []
  stresses: []
  applications:
    - mechanisms
    - structures
properties:
  - benchmark: density
    value: 7.87
    unit: g/cc
    scope: material
    conditions:
      processing: cold drawn
      temperature: not stated
    method: Physical Properties table, Metric column, value as printed
    status: ground
    source: elgin-1018
    where: Physical Properties table (Density row)
  - benchmark: elastic_modulus
    value: 200
    unit: GPa
    scope: material
    conditions:
      processing: cold drawn
      temperature: not stated
    method: Mechanical Properties table, Metric column, value as printed (the datasheet also prints 29000 ksi)
    status: ground
    source: elgin-1018
    where: Mechanical Properties table (Modulus of Elasticity row)
  - benchmark: ultimate_tensile_strength
    value: 440
    unit: MPa
    scope: material
    conditions:
      processing: cold drawn
      temperature: not stated
    method: Mechanical Properties table, Metric column, value as printed
    status: ground
    source: elgin-1018
    where: Mechanical Properties table (Tensile Strength, Ultimate row)
  - benchmark: yield_strength
    value: 370
    unit: MPa
    scope: material
    conditions:
      processing: cold drawn
      temperature: not stated
    method: Mechanical Properties table, Metric column, printed as Tensile Strength, Yield
    status: ground
    source: elgin-1018
    where: Mechanical Properties table (Tensile Strength, Yield row)
  - benchmark: elongation
    value: 15
    unit: '%'
    scope: material
    conditions:
      processing: cold drawn
      temperature: not stated
      gauge: 50 mm
    method: Mechanical Properties table, Metric column, value as printed
    status: ground
    source: elgin-1018
    where: Mechanical Properties table (Elongation at Break row, In 50 mm)
  - benchmark: reduction_of_area
    value: 40
    unit: '%'
    scope: material
    conditions:
      processing: cold drawn
      temperature: not stated
    method: Custom name (not in property-canon). Mechanical Properties table, value as printed
    status: ground
    source: elgin-1018
    where: Mechanical Properties table (Reduction of Area row)
  - benchmark: poissons_ratio
    value: 0.29
    unit: '-'
    scope: material
    conditions:
      processing: cold drawn
      temperature: not stated
      comment: Typical for steel (printed in the datasheet)
    method: Mechanical Properties table, value as printed
    status: ground
    source: elgin-1018
    where: Mechanical Properties table (Poissons Ratio row)
  - benchmark: shear_modulus
    value: 78
    unit: GPa
    scope: material
    conditions:
      processing: cold drawn
      temperature: not stated
      basis: estimated by the datasheet from the elastic modulus
    method: Mechanical Properties table; the datasheet marks this value as estimated
    status: ground
    source: elgin-1018
    where: Mechanical Properties table (Shear Modulus row)
  - benchmark: thermal_conductivity
    value: 51.9
    unit: W/m-K
    scope: material
    conditions:
      processing: cold drawn
      temperature: not stated
      basis: datasheet says estimated based on similar materials
    method: Thermal Properties table, value as printed; the datasheet marks it as estimated
    status: ground
    source: elgin-1018
    where: Thermal Properties table (Thermal Conductivity row)
  - benchmark: specific_heat
    value: 0.486
    unit: J/g-°C
    scope: material
    conditions:
      processing: annealed
      temperature: 100 °C or above
    method: Thermal Properties table, value as printed; printed beside the annealed condition
    status: ground
    source: elgin-1018
    where: Thermal Properties table (Specific Heat Capacity row)
  - benchmark: electrical_resistivity
    value: 0.0000159
    unit: ohm-cm
    scope: material
    conditions:
      processing: annealed
      temperature: 0 °C
    method: Electrical Properties table, first row, value as printed
    status: ground
    source: elgin-1018
    where: Electrical Properties table (Electrical Resistivity row, annealed condition at 0 °C)
  - benchmark: density
    value: 7.67
    value_high: 7.86
    bound: range
    unit: kg/dm³
    scope: material
    conditions:
      processing: not stated (form not given in the database entry)
      temperature: 0 to 30 °C
    method: AISI 1018 Physical Properties block, range as printed
    status: ground
    source: totalmateria-1018
    where: AISI 1018 Physical Properties (Density row)
  - benchmark: elastic_modulus
    value: 190
    value_high: 210
    bound: range
    unit: GPa
    scope: material
    conditions:
      processing: not stated (form not given in the database entry)
      temperature: 0 to 30 °C
    method: AISI 1018 Physical Properties block, range as printed
    status: ground
    source: totalmateria-1018
    where: AISI 1018 Physical Properties (Modulus of Elasticity row)
  - benchmark: poissons_ratio
    value: 0.27
    value_high: 0.3
    bound: range
    unit: '-'
    scope: material
    conditions:
      processing: not stated (form not given in the database entry)
      temperature: 0 to 30 °C
    method: AISI 1018 Physical Properties block, range as printed
    status: ground
    source: totalmateria-1018
    where: AISI 1018 Physical Properties (Poisson Coefficient row)
  - benchmark: density
    value: 7.9
    unit: g/cm³
    scope: material
    conditions:
      processing: hot rolled
      temperature: 23 °C
    method: Properties table on the hot-rolled page, value as printed at 23.0 °C
    status: ground
    source: mfgrobots-1018-hr
    where: AISI 1018 Hot Rolled Steel properties (General, Density row)
  - benchmark: elastic_modulus
    value: 210
    unit: GPa
    scope: material
    conditions:
      processing: hot rolled
      temperature: 23 °C
    method: Properties table on the hot-rolled page, value as printed at 23.0 °C
    status: ground
    source: mfgrobots-1018-hr
    where: AISI 1018 Hot Rolled Steel properties (Mechanical, Elastic modulus row)
  - benchmark: ultimate_tensile_strength
    value: 430
    unit: MPa
    scope: material
    conditions:
      processing: hot rolled
      temperature: 23 °C
    method: Properties table on the hot-rolled page, value as printed at 23.0 °C
    status: ground
    source: mfgrobots-1018-hr
    where: AISI 1018 Hot Rolled Steel properties (Mechanical, Tensile strength row)
  - benchmark: yield_strength
    value: 240
    unit: MPa
    scope: material
    conditions:
      processing: hot rolled
      temperature: 23 °C
    method: Properties table on the hot-rolled page, value as printed at 23.0 °C
    status: ground
    source: mfgrobots-1018-hr
    where: AISI 1018 Hot Rolled Steel properties (Mechanical, Yield strength row)
  - benchmark: elongation
    value: 27
    unit: '%'
    scope: material
    conditions:
      processing: hot rolled
      temperature: 23 °C
      gauge: not stated
    method: Properties table on the hot-rolled page, value as printed at 23.0 °C
    status: ground
    source: mfgrobots-1018-hr
    where: AISI 1018 Hot Rolled Steel properties (Mechanical, Elongation row)
  - benchmark: poissons_ratio
    value: 0.29
    unit: '-'
    scope: material
    conditions:
      processing: hot rolled
      temperature: 23 °C
      comment: Typical for Low Carbon Steel (printed on the page)
    method: Properties table on the hot-rolled page, value as printed
    status: ground
    source: mfgrobots-1018-hr
    where: AISI 1018 Hot Rolled Steel properties (Mechanical, Poisson's ratio row)
  - benchmark: specific_heat
    value: 450
    unit: J/(kg·K)
    scope: material
    conditions:
      processing: hot rolled
      temperature: 23 °C
    method: Properties table on the hot-rolled page, value as printed at 23.0 °C
    status: ground
    source: mfgrobots-1018-hr
    where: AISI 1018 Hot Rolled Steel properties (Thermal, Specific heat capacity row)
  - benchmark: melting_point
    value: 1480
    value_high: 1526
    bound: range
    unit: °C
    scope: material
    conditions:
      processing: hot rolled
      comment: Typical for Low Carbon Steel (printed on the page)
    method: Properties table on the hot-rolled page, range as printed
    status: ground
    source: mfgrobots-1018-hr
    where: AISI 1018 Hot Rolled Steel properties (Thermal, Melting point row)
  - benchmark: thermal_conductivity
    value: 25
    value_high: 93
    bound: range
    unit: W/(m·K)
    scope: material
    conditions:
      processing: hot rolled
      temperature: 23 °C
      comment: Typical for Low Carbon Steel (printed on the page)
    method: Properties table on the hot-rolled page, range as printed
    status: ground
    source: mfgrobots-1018-hr
    where: AISI 1018 Hot Rolled Steel properties (Thermal, Thermal conductivity row)
  - benchmark: curie_temperature
    value: 770
    unit: °C
    scope: material
    conditions:
      processing: hot rolled
      comment: Typical for Low Carbon Steel (printed on the page)
    method: Magnetic table on the hot-rolled page, value as printed
    status: ground
    source: mfgrobots-1018-hr
    where: AISI 1018 Hot Rolled Steel properties (Magnetic, Curie temperature row)
corrosion:
  - environment: Moist air, with or without salt (atmospheric rusting)
    headline: Carbon steel is susceptible to rust in moist air, and salt makes it worse. No 1018 corrosion rate was read.
    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 another protective material.
    rating: unknown
    conditions:
      humidity: high moisture
      salt: adds to the attack
    source: wiki-carbon-steel
    where: Carbon steel article, corrosion paragraph
  - environment: Industrial atmosphere with chloride and SO2 (wetting-drying lab simulation of low carbon steel)
    headline: A particular chloride to sulfur ratio gave much lower rust corrosion rates than expected in the lab simulation.
    effect: Rendon and Valencia simulated the wetting-drying cycle on low carbon steel from industrial atmospheres at different distances from the sea. Coupon electrode potential and rust layers were analysed. At one chloride to sulfur ratio, corrosion rates were much less than expected, which the authors attribute to a kinetic mechanism for rust layer formation.
    rating: unknown
    conditions:
      test: wetting-drying cycle in a CEBELCOR type apparatus
      ratio: a particular chloride to sulfur ratio
    source: rendon-valencia-2003
    where: Abstract
  - environment: Moisture in air (rust as an iron oxide)
    headline: Rust is an iron oxide that forms from iron, oxygen and water or air moisture.
    effect: Per Wikipedia, rust is an iron oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Rust consists of hydrous iron(III) oxides and iron(III) oxide-hydroxide. A stable rust can protect iron only when it is kept free of moisture.
    rating: unknown
    conditions:
      humidity: water or air moisture
    source: wiki-rust
    where: Lead paragraph and Stable rust paragraph
risks:
  hazards:
    - text: 'PubChem aggregated GHS for elemental manganese (Danger): H372 causes damage to organs through prolonged or repeated exposure; H228 flammable solid appears in 11.6 percent of reports. The record says 46.1 percent of 3101 reports do not meet GHS criteria. 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 (Danger signal in notifications): not classified in 74.1 percent of 6013 reports; H228 flammable solid appears in 15.5 percent. It covers the metal, not the solid steel.'
      ghs:
        - H228
      source: pubchem-fe
      where: Safety and Hazards, GHS Classification
  failure_risks:
    - mode: Atmospheric rusting of uncoated surfaces
      trigger: Moist air, high moisture, or salt
      consequence: Iron oxide rust forms on the surface, and it protects the steel only where it stays dry (Wikipedia, Rust)
      source: wiki-rust
      where: Lead paragraph and Stable rust paragraph
    - mode: Rust rate changed by industrial atmosphere
      trigger: Chloride and sulfur dioxide in industrial air with wetting and drying
      consequence: The rust layer and its corrosion rate depend on the chloride to sulfur ratio (lab simulation)
      source: rendon-valencia-2003
      where: Abstract
  side_effects: []
  handling:
    - text: Class A bars are cold drawn and then stress relieved at not less than 288 °C (Total Materia heat treatment note)
      source: totalmateria-1018
      where: AISI 1018 Heat Treatments
    - text: Carburising raises the surface hardness of low carbon steel (Wikipedia, Mild steel)
      source: wiki-mild-steel
      where: Lead paragraph
    - text: Cold drawn and hot rolled 1018 have different strength. Every strength value is recorded with its processing condition, and the two must not be mixed.
      source: elgin-1018
      where: Mechanical Properties table, datasheet title
  mitigations:
    - text: Shield from corrosion by painting, varnishing or applying another protective coating (Wikipedia, Carbon steel)
      source: wiki-carbon-steel
      where: Corrosion paragraph
    - text: Control moisture in the atmosphere; silica gel packets are one example for equipment shipped by sea (Wikipedia, Rust)
      source: wiki-rust
      where: Prevention paragraph
    - text: Use a stainless alloy with chromium where corrosion resistance is essential (Wikipedia, Carbon steel)
      source: wiki-carbon-steel
      where: Corrosion paragraph
uses:
  - application: mechanisms
    device: Shafts, pins and gears
    example: Shafts, pins and gears are frequently named as common uses for 1018; MWAlloys also names carburised pins and gears
    source: misumi-1018
    where: Best Manufacturing Uses list
  - application: structures
    device: Low-stress structural components
    example: Structural components for low-stress construction applications
    source: misumi-1018
    where: Best Manufacturing Uses list
  - application: structures
    device: Car parts, pipes and construction steel
    example: Typical applications of low carbon steel are car parts, pipes, construction, and food cans
    source: wiki-carbon-steel
    where: Low-carbon steel section
supply:
  - subject: Iron and steel (United States)
    abundance: Iron is the least expensive and most widely used metal (USGS). US raw steel production was 82 million t in 2025 (estimated), and net import reliance was 13 percent of apparent consumption in 2025 (estimated). Construction took about 31 percent of net shipments, and automotive about 15 percent.
    producers: []
    critical_lists: []
    recycling: Not read in this chapter, which points to a separate Iron and Steel Scrap chapter
    substitutes:
      - Aluminum and plastics in automotive; aluminum, concrete and wood in construction (USGS substitutes text)
    source: usgs-iron-steel-2026
    where: Domestic Production and Use; Salient Statistics; Substitutes
  - subject: Raw steel production by country (2025, estimated)
    abundance: World raw steel production was 1,900 million t in 2025 (estimated, rounded total). Shares below are computed from the printed tonnage over that total.
    producers:
      - country: China
        share_percent: 51.6
        year: 2025
      - country: India
        share_percent: 8.4
        year: 2025
      - country: United States
        share_percent: 4.3
        year: 2025
      - country: Japan
        share_percent: 4.3
        year: 2025
      - country: Russia
        share_percent: 3.4
        year: 2025
    critical_lists: []
    recycling: ''
    substitutes: []
    source: usgs-iron-steel-2026
    where: World Production table (Raw steel, 2025e)
  - subject: Steel mill product imports by source (2021 to 2024)
    abundance: Canada 23 percent, Mexico 15 percent, Brazil 13 percent, Republic of Korea 9 percent, other 40 percent (USGS).
    producers: []
    critical_lists: []
    recycling: ''
    substitutes: []
    source: usgs-iron-steel-2026
    where: Import Sources (2021 to 2024)
media: []
documents:
  - title: Carbon Steel Grade 1018 Data Sheet (Elgin), AISI 1018 Steel, cold drawn
    type: datasheet
    url: https://www.mwcomponents.com/uploads/Resource-Center/Elgin-Material-Sheets/Carbon-Steel-Grade-1018-Data-Sheet_Elgin.pdf
  - title: 'MatWeb datasheet printout: AISI 1018 Steel, cold drawn (hosted by QuickParts)'
    type: database
    url: https://quickparts.com/wp-content/uploads/2024/05/Steel-1018.pdf
  - title: 'Total Materia: AISI 1018 Structural and constructional steels'
    type: database
    url: https://www.totalmateria.com/en-us/material/1250012
  - title: 'MfgRobots: AISI 1018 Hot Rolled Steel, Properties and Applications'
    type: datasheet
    url: https://www.mfgrobots.com/Article/material/metal/35865.html
  - 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: 'Rendon and Valencia: Kinetics of structural rust transformation in environments containing chloride and SO2'
    type: paper
    url: https://revistademetalurgia.revistas.csic.es/index.php/revistademetalurgia/article/download/1089/1101/1106
    year: 2003
  - 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
  - title: 'MWAlloys: AISI/SAE 1018 Cold-Rolled Steel Coil'
    type: datasheet
    url: https://www.mwalloys.com/product/aisi-sae-1018-cold-rolled-steel-coil/
  - title: 'MWAlloys: 1018 Steel Plate (AISI 1018 / UNS G10180), cold rolled'
    type: datasheet
    url: https://www.mwalloys.com/product/aisi-sae-1018-cold-rolled-steel-plate/
gaps:
  - The hot-rolled strength and elongation values come from one page, MfgRobots, which prints generic typical values with no mill certificate. The MatWeb hot-rolled entry, MakeItFrom and the live MatWeb cold-drawn page were blocked to the fetch tool (Cloudflare or JavaScript challenge), so the cold-drawn figures come from the Elgin datasheet and a MatWeb printout hosted by QuickParts.
  - Carbon is printed as 0.14 to 0.20 by MatWeb and Elgin, and as 0.15 to 0.20 by Total Materia, MISUMI, MWAlloys and MfgRobots. The recipe uses the MatWeb and Elgin range.
  - The Total Materia tensile range of 380 to 690 MPa spans several conditions and is not recorded. The MISUMI page gives 440 to 540 MPa tensile and 370 MPa yield without a processing condition, so it is not recorded either.
  - Coefficient of thermal expansion (1.2E-5 1/K) and electrical resistivity (1.43E-7 to 1.74E-7 ohm m) on the MfgRobots page are not recorded, because the gate text match cannot find values printed in E notation with an uppercase E.
  - No ASTM A108, AMS 5069 or ASTM A29 minimum values were read from a fetched page, so no specified minimum strength is recorded.
  - The Elgin specific heat and electrical resistivity are annealed-condition values printed on the cold-drawn sheet, and are recorded as annealed. Its thermal conductivity and shear modulus are datasheet estimates, and are marked as such.
  - The Total Materia density, modulus and Poisson values give no form, and are recorded as not stated. The Elgin reduction of area uses a custom name, reduction_of_area, which is not in property-canon.
  - No 1018 atmospheric corrosion rate was read. The Rendon and Valencia paper is a lab wetting-drying study of low carbon steel, and its rate table was not extracted. Field studies found in search results were not fetched and are not used.
  - The hazard records are PubChem entries for elemental manganese and iron, mostly from notifications for the metal rather than the solid steel. No 1018 safety data sheet was read, and the NIOSH and CDC welding-fume pages were blocked to the fetch tool, so fume and dust limits are not recorded.
  - The USGS iron and steel chapter lists no critical minerals, so critical_lists is empty. Iron ore feedstock (the Iron Ore chapter) and scrap recycling shares (the Iron and Steel Scrap chapter) were not read.
  - Producer shares are computed from printed tonnages over the rounded world total of 1,900 million t.
  - No sourced data was read for fatigue, cryogenic behaviour, fire or high-temperature strength of 1018.
  - 'Designations not read: the Continental Steel, Metal Supermarkets and Zoro grade pages returned a bot-check page when fetched in this run, so no codes from them are recorded.'
  - 'Designations left out: MWAlloys says C15E and CK15 are sometimes called 1.0401, and its coil page gives Ck15 as a historical DIN and EN equivalent. By general knowledge C15E and Ck15 are the 1.1141 steel, which was not checked against an EN or DIN standard in this run.'
  - 'Designations left out: GB Q235 (MWAlloys says not a direct match) and the national names outside the requested systems (AS, AFNOR, GOST, BS 080M15, GB 15 steel, CSN, NBN, COPANT and the rest of the Elgin key-word list) were not added. SAE J403 names the composition spec, not the grade, so it is not added either.'
  - DIN 1.0453 and DIN C16.8 come from the Elgin key-word list, which names records rather than giving an equivalence table, so check them before treating them as the same grade.
  - The product-form notes on A29, A519 and A576 follow the MWAlloys wording, and the ASTM standards themselves were not read in this run.
sources:
  elgin-1018:
    title: Carbon Steel Grade 1018 Data Sheet (Elgin), AISI 1018 Steel, cold drawn
    url: https://www.mwcomponents.com/uploads/Resource-Center/Elgin-Material-Sheets/Carbon-Steel-Grade-1018-Data-Sheet_Elgin.pdf
    kind: datasheet
    license: cited, not reproduced
  matweb-1018-cd:
    title: 'MatWeb datasheet printout: AISI 1018 Steel, cold drawn (hosted by QuickParts, printed 5/15/23)'
    url: https://quickparts.com/wp-content/uploads/2024/05/Steel-1018.pdf
    kind: database
    license: cited, not reproduced
  totalmateria-1018:
    title: 'Total Materia: AISI 1018 Structural and constructional steels'
    url: https://www.totalmateria.com/en-us/material/1250012
    kind: database
    license: cited, not reproduced
  mfgrobots-1018-hr:
    title: 'MfgRobots: AISI 1018 Hot Rolled Steel, Properties and Applications'
    url: https://www.mfgrobots.com/Article/material/metal/35865.html
    kind: web
    license: cited, not reproduced
  misumi-1018:
    title: 'MISUMI: 1018 steel (blog)'
    url: https://us.misumi-ec.com/blog/1018-steel/
    kind: web
    license: cited, not reproduced
  mwalloys-1018:
    title: 'MWAlloys: AISI / SAE 1018 Cold-Rolled Steel Coil'
    url: https://www.mwalloys.com/product/aisi-sae-1018-cold-rolled-steel-coil/
    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
  rendon-valencia-2003:
    title: 'Rendon and Valencia (2003): Kinetics of structural rust transformation in environments containing chloride and SO2, Revista de Metalurgia'
    url: https://revistademetalurgia.revistas.csic.es/index.php/revistademetalurgia/article/download/1089/1101/1106
    kind: paper
    year: 2003
    license: open access (cited)
  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)
  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-mild-steel:
    title: 'Wikipedia: Mild steel'
    id: Mild steel
    url: https://en.wikipedia.org/wiki/Mild_steel
    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)
  mwalloys-1018-plate:
    title: 'MWAlloys: 1018 Steel Plate (AISI 1018 / UNS G10180), cold rolled'
    url: https://www.mwalloys.com/product/aisi-sae-1018-cold-rolled-steel-plate/
    kind: web
    license: cited, not reproduced
license: CC-BY-4.0
updated: '2026-10-24'
review:
  status: draft
  method: assistant
  checked_values: 24
  unreachable: 0
  caveats: 4
  note: 'Read by an AI assistant on 2026-10-24 from pages fetched in that run. Strength values are split by processing: cold drawn from the Elgin datasheet, hot rolled from the MfgRobots page. The MatWeb printout matches the Elgin cold-drawn figures. Carbon is printed as 0.14 to 0.20 (MatWeb, Elgin) and 0.15 to 0.20 (Total Materia). Hot-rolled values are generic typical values, not a mill certificate.'
story:
  recipe:
    line: AISI 1018 is iron with 0.14 to 0.20 percent carbon, 0.60 to 0.90 percent manganese, and maximum 0.040 percent phosphorus and 0.050 percent sulfur (Elgin datasheet, MatWeb printout). It is sold as hot-rolled or cold-drawn bar, and cold drawing raises its strength (MISUMI, MWAlloys).
    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: elgin-1018
        where: Component table
      - name: Carbon
        symbol: C
        share_percent: 0.14
        share_high: 0.2
        role: Sets the strength and hardness of the low-carbon steel. A low level keeps it easy to machine and weld (Wikipedia, Carbon steel).
        source: elgin-1018
        where: Component table
      - name: Manganese
        symbol: Mn
        share_percent: 0.6
        share_high: 0.9
        role: Improves hardenability, which Wikipedia notes is often its purpose in low-carbon steels.
        source: elgin-1018
        where: Component table
      - name: Phosphorus
        symbol: P
        share_note: max 0.040
        role: Impurity held to a maximum limit.
        source: elgin-1018
        where: Component table
      - name: Sulfur
        symbol: S
        share_note: max 0.050
        role: Impurity held low. Trace sulfur makes steel brittle at high working temperatures (Wikipedia, Carbon steel).
        source: elgin-1018
        where: Component table
  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 1018 safety data sheet was read.
      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 as not classified in most reports, with H228 (flammable solid) in some notifications.
        - label: Workshop
          line: Cutting, grinding and welding make metal dust and fume. The fume and dust limits were not read, 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 1018 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: Industrial air
          line: In a lab wetting-drying simulation, a particular chloride to sulfur ratio gave much lower rust rates than expected (Rendon and Valencia).
    - title: Fabrication and heat
      level: 1
      verdict: Cold drawn bar needs stress relief
      lead: Cold drawing changes the strength, so the processing must be stated with every value.
      points:
        - label: Stress relief
          line: Class A cold-drawn bars are stress relieved at not less than 288 °C (Total Materia).
        - label: Carburising
          line: Carburising raises the surface hardness of low carbon steel (Wikipedia, Mild steel).
  why: AISI 1018 is the everyday plain low-carbon steel. It is chosen for cost, for easy machining and welding, and for shafts, pins and gears. Its strength depends on processing, since the cold-drawn bar has a higher yield strength than the hot-rolled bar. Its weak point is rust in moist air and salt.
  uses:
    - where: Shafts, pins and gears
      line: MISUMI lists shafts, pins and gears among common uses of 1018, and MWAlloys names carburised pins and gears.
    - where: Structural components
      line: MISUMI lists structural components for low-stress construction applications.
    - where: Car parts, pipes and construction
      line: Wikipedia lists car parts, pipes, construction and food cans as typical uses of low carbon steel.
  can_do:
    - label: Strength, cold drawn
      benchmark: ultimate_tensile_strength
      line: The cold-drawn datasheet gives 440 MPa ultimate and 370 MPa yield.
    - label: Strength, hot rolled
      benchmark: ultimate_tensile_strength
      line: The hot-rolled page gives 430 MPa ultimate and 240 MPa yield. These are separate from the cold-drawn figures.
    - label: Stiffness
      benchmark: elastic_modulus
      line: The elastic modulus is 200 GPa in the cold-drawn datasheet and 210 GPa on the hot-rolled page. Total Materia gives 190 to 210 GPa with no form stated.
    - label: Density
      benchmark: density
      line: Density is 7.87 g/cc in the datasheet and 7.9 g/cm³ on the hot-rolled page.
  compare: 'AISI 1018 is a plain low-carbon steel. It trades corrosion resistance for low cost, easy machining and welding, and it rusts in moist air where stainless steel would not. The cold-drawn and hot-rolled bars differ: 440 against 430 MPa ultimate, but 370 against 240 MPa yield and 15 against 27 percent elongation. Because the two conditions differ, every strength value here carries its processing condition.'
  compare_rows:
    - label: Density
      benchmark: density
      scope: material
    - label: Stiffness
      benchmark: elastic_modulus
      scope: material
    - label: Yield strength
      benchmark: yield_strength
      scope: material
  handling:
    - Specify the processing condition, cold drawn or hot rolled, with every strength value, because the two differ (Elgin, MfgRobots).
    - Stress relieve Class A cold-drawn bars at not less than 288 °C after drawing (Total Materia).
    - Carburise where a hard surface is needed on pins and gears (Wikipedia, Mild steel).
  good_for:
    - Machined shafts, pins and gears, where machining and cost matter (MISUMI).
    - Coated structural parts for low-stress construction (MISUMI, Wikipedia).
  watch_out:
    - Moist air and salt cause rust. Paint or another coating is needed outdoors (Wikipedia, Carbon steel).
    - 'Strength depends on processing: cold drawn and hot rolled 1018 are not interchangeable in the figures.'
    - Carbon is printed as 0.14 to 0.20 in some sources and 0.15 to 0.20 in others.
  verdict: 'AISI 1018 is the everyday plain low-carbon steel: cheap, easy to machine and weld, and moderately strong. It rusts in moist air, so coat it. State the cold-drawn or hot-rolled condition with every strength value.'