Physical properties
Melting point of steel and stainless steel, grade by grade
Stainless steel 304 (UNS S30400) melts at 1400 to 1450 °C (2552 to 2642 °F), according to AZoM and Wikipedia. Stainless steel 316 (UNS S31600) melts at 1390 to 1440 °C (2534 to 2624 °F) in the UPMET data sheet and at 1375 to 1400 °C in the AZoM table. Steel has no single melting point: the printed melting ranges of the 27 steel and stainless steel grades in our data lie between 1300 °C (2372 °F) and 1532 °C (2790 °F).
- Need a number for 304 or 316 stainless steel? Use stainless steel 304 at 1400 to 1450 °C (AZoM, Wikipedia) and stainless steel 316 at 1390 to 1440 °C (UPMET), and quote the range, not one value.
- Need a number for plain steel? Our two records are carbon steel 1018 hot rolled at 1480 to 1526 °C (MfgRobots) and alloy steel 4130 at 1432 °C (Titanium Industries, one printed value). Other carbon and alloy steels have no melting record in any source we hold.
- Using the number for a design? Do not. In every row of the service-limit chart the printed limit is at least 278 °C below the start of melting; see what the range means in practice.
- Melting range
- the span of temperatures between the start of melting and the end of melting, as a data sheet prints it.
- Solidus
- the temperature at which melting starts; below it the steel is fully solid.
- Liquidus
- the temperature at which melting ends; above it the steel is fully liquid.
- UNS number
- the Unified Numbering System code of an alloy, such as S30400; the same alloy has other names in EN, AISI and JIS.
- Austenitic, ferritic, martensitic
- the three main families of stainless steel, named for their crystal structure; duplex steels mix two of them.
- Precipitation-hardening (PH)
- a stainless family strengthened by a heat treatment that forms fine particles, such as 17-4 PH.
Which steel grades are solid, partly melted or liquid at a given temperature?
At any temperature each of the 27 grades below is fully solid, partly melted (inside its printed melting range), fully liquid, or undecided because only one value is printed. At the starting 1420 °C (2588 °F) the count is 5 fully solid, 15 partly melted and 3 fully liquid. Each column is one grade; move the slider to change the temperature.
At 1420 °C (2588 °F): 5 fully solid, 15 partly melted, 3 fully liquid, 4 cannot tell.
- Cool tint: below the printed start of melting (solid)
- Bar: the printed melting range
- Warm tint: above the printed end (liquid)
- Diamond: a single printed value
- Hollow diamond: liquidus only, no start printed
- Two bars side by side: two sources that differ
Fully solid 5
Below the printed start of melting.
Partly melted 15
Inside a printed melting range: solid and liquid together.
Fully liquid 3
Above the printed end of melting, or past a single printed value.
Cannot tell 4
Only one value is printed, or two sources disagree at this temperature.
This shows only where each printed melting range sits. It says nothing about strength, which falls long before the bottom of the range, or about scaling, creep and fire. The service-limit section below puts the two side by side.
Which family of stainless steel melts at the lowest temperature?
In our data the austenitic stainless family has the lowest start of melting, 1300 °C (904L), and the martensitic stainless family has the highest end, 1532 °C (410). The two plain steels, 1018 and 4130, lie between 1432 and 1526 °C. Each card gives the lowest start and the highest end printed for any grade in the family, including alternative sources.
Austenitic stainless
1300 to 1455 °C
2372 to 2651 °F · 14 grades
Ferritic stainless
1425 to 1510 °C
2597 to 2750 °F · 2 grades
Martensitic stainless
1371 to 1532 °C
2500 to 2790 °F · 5 grades
Duplex stainless
1385 to 1443 °C
2525 to 2629 °F · 2 grades
Precipitation-hardening stainless
1404 to 1440 °C
2559 to 2624 °F · 2 grades
Ranges inside a family overlap, and neighbouring grades often share one table, so a few degrees between two bars is not a real difference between two steels. In 4 cases two grades print exactly the same range (301 and 304L; 316L and 317L; 321 and 347; 17-4 PH and 17-7 PH). The widest printed range is 111 °C (440C); the narrowest is 20 °C (303).
What is the melting range of each steel and stainless steel grade?
The melting range of each of the 27 grades is in the table below in °C and °F, from 904L at 1300 to 1390 °C to 410 at 1482 to 1532 °C. 5 grades print one value instead of a range. Values are converted from the printed unit and rounded to whole degrees, and each grade links to its profile, which lists every source. The CSV file holds the same rows with source addresses.
| Grade | Melting range (°C) | Melting range (°F) | As printed (unit shown) | Type | Source |
|---|---|---|---|---|---|
| Austenitic stainless | |||||
| 904L | 1300 to 1390 °C | 2372 to 2534 °F | 1300 to 1390 °C | melting range | Sandmeyer |
| 309 | 1399 to 1454 °C | 2550 to 2650 °F | 2550 to 2650 °F | melting range | NKS · The NKS range is printed for 309 and 309S together |
| 1371 to 1421 °C | 2500 to 2590 °F | 2500 to 2590 °F | melting range | Rolled Alloys | |
| 316 | 1390 to 1440 °C | 2534 to 2624 °F | 1390 to 1440 °C | melting range | UPMET · One UPMET table covers 316 and 316L |
| 1375 to 1400 °C | 2507 to 2552 °F | 1648 to 1673 K | melting range | AZoM | |
| 316L | 1390 to 1440 °C | 2534 to 2624 °F | 1390 to 1440 °C | melting range | UPMET · One UPMET table covers 316 and 316L |
| 317L | 1390 to 1440 °C | 2534 to 2624 °F | 1390 to 1440 °C | melting range | ATI · One ATI table covers 316, 316L, 317 and 317L |
| 321 | 1398 to 1446 °C | 2548 to 2635 °F | 1398 to 1446 °C | melting range | UPMET |
| 347 | 1398 to 1446 °C | 2548 to 2635 °F | 1398 to 1446 °C | melting range | UPMET |
| 301 | 1399 to 1421 °C | 2550 to 2590 °F | 1399 to 1421 °C | melting range | ATI |
| 304L | 1399 to 1421 °C | 2550 to 2590 °F | 1399 to 1421 °C | melting range | ATI · One ATI table covers 302, 304, 304L and 305 |
| 347H | 1399 to 1446 °C | 2550 to 2635 °F | 2550 to 2635 °F | melting range | Rolled Alloys · One Rolled Alloys bulletin covers 347 and 347H |
| 302 | 1420 °C | 2588 °F | 1420 °C | single value | Alloy Wire International |
| 1400 °C | 2552 °F | 1400 °C | single value | RoyMech | |
| 304 | 1400 to 1450 °C | 2552 to 2642 °F | 1673 to 1723 K | melting range | AZoM and Wikipedia |
| 303 | 1455 °C | 2651 °F | 1455 °C | single value | Aalco |
| 1400 to 1420 °C | 2552 to 2588 °F | 1400 to 1420 °C | melting range | Ulbrich | |
| 310S | 1410 °C | 2570 °F | 1410 °C | liquidus only | Aperam |
| Ferritic stainless | |||||
| 430 | 1425 to 1510 °C | 2597 to 2750 °F | 1425 to 1510 °C | melting range | ATI |
| 430F | 1482 °C | 2700 °F | 1482 °C | single value | Ambica |
| Martensitic stainless | |||||
| 440C | 1371 to 1482 °C | 2500 to 2700 °F | 2500 to 2700 °F | melting range | Rolled Alloys |
| 420 | 1454 to 1510 °C | 2650 to 2750 °F | 2650 to 2750 °F | melting range | Rolled Alloys |
| 410S | 1480 to 1530 °C | 2696 to 2786 °F | 1480 to 1530 °C | melting range | Jacquet |
| 410 | 1482 to 1532 °C | 2700 to 2790 °F | 1482 to 1532 °C | melting range | UPMET |
| 416 | 1490 °C | 2714 °F | 2714 °F | single value | Rolled Alloys |
| Duplex stainless | |||||
| 2205 | 1385 to 1441 °C | 2525 to 2625 °F | 2525 to 2625 °F | melting range | Rolled Alloys |
| 2101 | 1385 to 1443 °C | 2525 to 2630 °F | 2525 to 2630 °F | melting range | Rolled Alloys |
| Precipitation-hardening stainless | |||||
| 17-4 PH | 1404 to 1440 °C | 2559 to 2624 °F | 1404 to 1440 °C | melting range | UPMET |
| 17-7 PH | 1404 to 1440 °C | 2559 to 2624 °F | 1404 to 1440 °C | melting range | UPMET |
| Carbon and alloy steel | |||||
| 4130 | 1432 °C | 2610 °F | 2610 F | single value | Titanium Industries |
| 1018 | 1480 to 1526 °C | 2696 to 2779 °F | 1480 to 1526 °C | melting range | MfgRobots |
"Single value" means the source prints one temperature and does not say whether it is the start or the end of melting. "Liquidus only" (310S) means the temperature at which melting is complete; the start is not printed. Neither is a range, so the ladder draws them as diamonds.
Why does steel melt over a range, not at one temperature?
Steel melts over a range because steel is a mixture. A pure metal melts at one temperature. A mixture such as steel starts to melt at one temperature, the solidus, and is fully liquid only at a higher one, the liquidus. Between the two there is slush: solid crystals sitting in liquid. This is general engineering knowledge, not something our data proves. What the data sheets give us are the two ends, or only one number.
A grade is also a band of compositions, not one recipe. The profiles hold the limits the standards allow, in weight percent:
- 304
- chromium 18 to 20, nickel 8 to 11
- 316L
- chromium 16 to 18, nickel 10 to 14, molybdenum 2 to 3
- 440C
- carbon 0.95 to 1.2, chromium 16 to 18
- 1018
- carbon 0.14 to 0.2, manganese 0.6 to 0.9
Two heats that both meet the grade can have slightly different melting temperatures. The printed range is for the grade, not for the bar on your bench. That is general engineering knowledge too.
What the ladder does show about composition
In our data the grade that starts melting lowest is 904L, at 1300 to 1390 °C; the profile gives 24.2 % nickel and 4.3 % molybdenum (nominal). The grades that end highest are the 12% chromium martensitic steels such as 410 (1482 to 1532 °C), with nickel up to 0.75 %. That looks like a nickel pattern. It is not a rule: 440C has no required nickel but about 0.95 to 1.2 % carbon, and starts melting at 1371 °C, below 304 at 1400 °C. Our sources do not explain why, and they were not measured under one method, so we report the pattern and draw no conclusion about cause.
Why the same grade has two answers
Sources round differently, quote different heats, and print one table for several grades. 4 grades in our data have more than one record that does not agree on the range: 302, 303, 309, 316. The details are in the disagreement table. Where two records disagree here, they differ by tens of degrees, not hundreds.
What does the melting range mean for welding, heat treatment and fire?
Welding, heat treatment and hot service all happen below the melting range, and in our data every printed service limit sits at least 278 °C below the start of melting. Heat treatment gets closest: hot working of stainless steel 303 tops out 140 °C below where its melting starts. No source we hold covers fire resistance. The three uses are taken one at a time below.
Welding
A weld pool is steel taken above the liquidus. The metal beside it passes through the melting range on the way up and again on the way down. A wide range means more time as slush. This is general engineering knowledge, not in our data.
- The 309 profile records hot cracking in welds. Jacquet ties it to high thermal expansion, low thermal conductivity and low ferrite in the weld metal; it does not name the melting range as a cause.
- For 17-4 PH the profile says multipass welds must be solution annealed before aging, to avoid oxyacetylene welding, and that plasma torch cutting can crack the annealed material.
- Two of the martensitic grades call for preheat: 410 to at least 350 to 400 °F before welding, 440C to about 250 °C then a full anneal. That is about hardening, not melting.
Heat treatment and hot working
These happen below the range, but not always far below. The table puts the top of each printed process range next to the start of melting. The smallest margins we hold are 303 hot working (140 °C) and 904L hot working (150 °C).
Our sources do not say how far a real furnace overshoots, so we draw no conclusion beyond the gap.
Hot service and fire
The range is the ceiling of what is still solid, and in our data the useful limits sit far below it. At 649 °C, 722 °C below the start of melting, 309 has a typical tensile strength of 379 MPa against 621 MPa at 25 °C (61 %), in one Jacquet table.
- Damage mechanisms sit far lower: the 316L profile says to avoid holding between 450 and 900 °C, and 2205 to avoid 343 to 530 °C and to keep prolonged exposure to 280 °C.
- We hold no fire-test, structural-fire or load-at-temperature data for the plain steels, so we give no fire rating and no safe temperature for a fire.
- The 301 profile records a safety-data-sheet statement that welding, burning, melting, sawing, brazing, grinding, buffing or polishing can release hexavalent chromium. Read the supplier's own safety sheet before hot work on any stainless grade.
How close do heat treatments get to the melting range?
| Grade | Process (as printed) | Top of printed range (°C) | Melting starts (°C) | Margin (°C) |
|---|---|---|---|---|
| 303 | Hot working, 1149 to 1260 °C (Aalco) | 1260 °C | 1400 °C | 140 °C |
| 904L | Hot working, 1150 to 850 °C (Outokumpu) | 1150 °C | 1300 °C | 150 °C |
| 904L | Solution anneal, 1060 to 1140 °C (Outokumpu, Sandmeyer) | 1140 °C | 1300 °C | 160 °C |
| 301 | Forging, initial, 2000 to 2200 °F (1093 to 1204 °C) (ATI) | 1204 °C | 1399 °C | 195 °C |
| 309 | Anneal hold, 2050 to 2150 °F (1120 to 1175 °C) (Jacquet) | 1175 °C | 1371 °C | 196 °C |
| 302 | Hot forming, 1200 to 900 °C (AGST) | 1200 °C | 1400 °C | 200 °C |
| 317L | Forging and rolling, 1150 to 800 °C (datasheet) | 1150 °C | 1390 °C | 240 °C |
| 2205 | Solution anneal, 1060 to 1120 °C (Langley) | 1120 °C | 1385 °C | 265 °C |
| 321 | Solution anneal, 1075 to 1125 °C (Swiss) | 1125 °C | 1398 °C | 273 °C |
| 2101 | Solution anneal, 1020 to 1080 °C (Atlas) | 1080 °C | 1385 °C | 305 °C |
| 440C | Hardening, 1010 to 1065 °C (Aalco) | 1065 °C | 1371 °C | 306 °C |
| 430F | Forging, heating, 1100 to 1130 °C (Deutsche Edelstahlwerke) | 1130 °C | 1482 °C | 352 °C |
Margin = the lowest printed start of melting minus the top of the printed process range, in whole degrees. Several grades print more than one process range or more than one melting range; we use the figures shown.
Data behind this chart
| Grade | Service or use limit (°C) | What the number is | Melting starts (°C) | Gap (°C) |
|---|---|---|---|---|
| 309 | 1093 °C | Oxidation rating, continuous service in air; not a mechanical limit | 1371 °C | 278 °C |
| 310S | 1100 °C | Continuous service (Goodfellow); Aperam prints 1050 °C in low-sulphur air | 1410 °C (liquidus only) | 310 °C or less |
| 316 | 925 °C | Service limit as printed by AZoM; form and temper not stated | 1375 °C | 450 °C |
| 302 | 925 °C | Continuous service in air (RoyMech) | 1400 °C | 475 °C |
| 321 | 850 °C | Continuous service, oxidising atmosphere | 1398 °C | 548 °C |
| 347H | 850 °C | Maximum use temperature in air, no duration given | 1399 °C | 549 °C |
| 430 | 870 °C | Intermittent service, oxidation resistance (continuous 790 to 815 °C) | 1425 °C | 555 °C |
| 301 | 840 °C | Oxidation resistance limit in air (ATI advises against 871 °C and above) | 1399 °C | 559 °C |
| 347 | 800 °C | Maximum use temperature in air, no duration given | 1398 °C | 598 °C |
| 410S | 705 °C | Continuous service limit | 1480 °C | 775 °C |
| 420 | 675 °C | Scaling resistance, continuous service (intermittent 760 °C) | 1454 °C | 779 °C |
| 416 | 675 °C | Scaling resistance, continuous service; not a mechanical limit | 1490 °C | 815 °C |
| 410 | 649 °C | Upper limit where scaling and oxidation resistance are needed | 1482 °C | 833 °C |
| 904L | 400 °C | Pressure-vessel approval limit; a design code limit | 1300 °C | 900 °C |
| 440C | 400 °C | Maximum use temperature, printed as about 400 °C | 1371 °C | 971 °C |
| 304L | 426 °C | ASME code coverage limit, not an oxidation or melting limit | 1399 °C | 973 °C |
| 2205 | 316 °C | ASME maximum (600 °F); prolonged exposure is limited to 280 °C (Alleima) | 1385 °C | 1069 °C |
| 2101 | 316 °C | Stated as useful up to this temperature, no duration given | 1385 °C | 1069 °C |
| 17-4 PH | 316 °C | High strength maintained to about this temperature | 1404 °C | 1088 °C |
Where do sources disagree on the melting range?
4 grades have records that disagree: 302, 303, 309, 316. The records differ by tens of degrees, and we show both values with both sources instead of choosing. Stainless steel 304 is the one grade where two sources print the same range, 1400 to 1450 °C, so the table lists it for comparison.
| Grade | What the records say | How to read it |
|---|---|---|
| 304 | AZoM and Wikipedia print the same range, 1400 to 1450 °C (1673 to 1723 K in the first). | The only grade where two sources agree. |
| 316 | UPMET: 1390 to 1440 °C. AZoM: 1375 to 1400 °C (printed 1648 to 1673 K). | The ranges overlap by 10 °C. We do not choose between them. 316L prints 1390 to 1440 °C, the same as the first. |
| 302 | Alloy Wire International: 1420 °C. RoyMech: 1400 °C. | Two single values, not ranges; the RoyMech imperial figure carries a formatting error in the source, per our profile. |
| 303 | Aalco: 1455 °C (one value). Ulbrich: 1400 to 1420 °C. | One source prints a single value above the end of the other's range; between 1420 and 1455 °C the ladder marks 303 "cannot tell". |
| 309 | NKS: 1399 to 1454 °C. Rolled Alloys: 1371 to 1421 °C. | The two sheets differ by 28 °C at the start. Our profile keeps both and picks none. |
| 410 and 410S | 1482 to 1532 °C (UPMET) and 1480 to 1530 °C (Jacquet). | Different grades. Both profiles note the range as 2700 to 2790 °F; the 2 °C difference is in the °C figures the sources print. Treat them as the same. |
What melting-point data is missing?
A melting range is not found in any source we hold for 16 grades we profile, including 2507 and 2304 duplex, 409, 1045, 4140, A36 and the tool steels, so they are not on the ladder. We do not fill gaps from memory. The list below also covers what the printed records leave open.
- Grades with no melting record. Not found in any source we hold: 2304, 2507, 409, 431, 444, 1010, 1045, 1070, 1215, 4140, 4340, A36, A2, D2, H13, P20.
- Solidus and liquidus. Only 310S prints a liquidus, and none prints a solidus on its own. The 17-4 PH record says outright "no solidus or liquidus split", so we do not know which end of each range is which temperature, only that the grade melts between them.
- 5 grades with a single value: 302, 310S, 430F, 416, 4130. For these the ladder cannot say whether the grade has started to melt below the printed value.
- Form, heat and test method. Most records say "not stated". Cast, wrought, rolled, wire and bar are not separated. The 1018 value is hot-rolled bar, typical for low-carbon steel, from one supplier page; the 4130 value is one table with no condition stated.
- Shared tables. Some grades take their range from a table that covers several grades (marked in the table above), so identical ranges are not independent measurements.
- Rounding. We convert kelvin and Fahrenheit and round to whole degrees. A degree here or there is conversion, not data.
- Strength at temperature, creep and fire. One grade has a clean hot-strength pair (309). Nothing we hold supports a statement about fire resistance or a maximum safe temperature for a structure.
Questions people ask
What is the melting point of steel?
There is no single figure, because steel is an alloy. Carbon steel 1018 hot-rolled bar melts at 1480 to 1526 °C (2696 to 2779 °F), a value MfgRobots prints as typical for low-carbon steel, and alloy steel 4130 at 1432 °C (2610 °F) as one printed number (Titanium Industries). Across all 27 grades the printed ranges lie between 1300 and 1532 °C. No source we hold gives a melting range for 1045, 4140, 4340, A36 or the tool steels.
What is the melting point of stainless steel in °C and °F?
Stainless steel melts between 1300 °C (2372 °F) for 904L and 1532 °C (2790 °F) for 410 in our data, depending on grade. Austenitic stainless steel 304 melts at 1400 to 1450 °C (2552 to 2642 °F) and 316 at 1390 to 1440 °C (2534 to 2624 °F); ferritic 430 at 1425 to 1510 °C and martensitic 410 at 1482 to 1532 °C. The values are printed data-sheet ranges, converted and rounded to whole degrees.
What is the melting point of 304 and 316 stainless steel?
304 is 1400 to 1450 °C (2552 to 2642 °F) in both AZoM and Wikipedia. 316 is 1390 to 1440 °C (2534 to 2624 °F) in the UPMET data sheet, which prints the same range for 316L; AZoM prints 1375 to 1400 °C for 316 once its kelvin values are converted. The two 316 sources overlap but do not agree, so we show both rather than choose.
Does stainless steel melt at a lower temperature than carbon steel?
Often, but not always. 304 finishes melting at 1450 °C, which is 30 °C below the 1480 °C where our 1018 record starts. But the 1482 to 1532 °C range of 410 overlaps the 1480 to 1526 °C of 1018, so a 12% chromium martensitic grade is not a low-melting stainless. Compare grade to grade on the ladder above, not family to family.
Why does steel not have one melting point?
Steel is a mixture, and a mixture usually starts to melt at one temperature and finishes at a higher one, with solid and liquid together between them; this is general engineering knowledge, not proven by our data. Our data shows that 22 of 27 grades are printed as a range, and that a grade is a composition band: 304 allows 18 to 20 % chromium and 8 to 11 % nickel.
Does steel need to reach its melting point to lose strength?
No. In our data every printed service limit is at least 278 °C below the start of melting (309 is the closest; 310S is left out because only its liquidus is printed). Jacquet's table gives stainless steel 309 a typical tensile strength of 379 MPa at 649 °C against 621 MPa at 25 °C (61 %). We hold no fire-test data and state no fire rating.
Keep reading
How this was made
Each grade is a profile in the Space Mushroom database. The profiles are drafted by AI assistants from the cited pages, and a script checks that every value appears in the source it cites; each profile page lists its sources. Every melting range on this page is read from those profiles and converted when the page is built, and every phrase about welding, heat treatment and service limits is checked against the profile it comes from, so it cannot drift from the data. A named reviewer has not yet signed this article. Conversions: °F = °C × 9/5 + 32, and K − 273.15 = °C, rounded to whole degrees.
Data checked 1 November 2026. Next review when a profile changes.
How to cite: "Melting point of steel and stainless steel, grade by grade", Space Mushroom, https://spacemushroom.com/articles/melting-point-of-steel-and-stainless-steel/, data checked 1 November 2026.