Stainless Steel 415-AW (As-welded deposit)
Heat-treated state
AISI/SAE 415 · UNS S41500 · ASTM A487 Gr CA6NM
Untempered fresh martensite in weld/HAZ — hard and low toughness; post-weld temper at 580–620 °C is normally required.
Values for the AW condition
Other 415 tempers and conditions
415 is listed in 7 conditions; see the grade overview at 415.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Quenched and tempered, Rm 650–850 MPa | Maximum-toughness condition for thick turbine castings/forgings and sour or low-temperature service. | 520 | 730 | 22 | 19 HRC | — |
Solution annealed | Softest supply condition for heavy machining or cold work before final quench-and-temper. | 550 | 720 | 22 | 17 HRC | — |
ASTM A487 Gr. CA6NM Class A, normalized and tempered casting | Cast counterpart used for hydro turbine runners and pump casings; same metallurgy, slightly lower minimum strength and ductility than wrought. | 690 | 830 | 18 | 24 HRC | — |
QT780Default Quenched and double tempered, Rm 780–980 MPa | Standard commercial condition: best balance of 620 MPa yield, high CVN and weldability — pick this unless a spec says otherwise. | 700 | 850 | 18 | 25 HRC | — |
Cold drawn | Small-diameter bar with tight tolerance and bright finish; slightly higher yield, lower ductility than QT780. | 780 | 900 | 14 | 29 HRC | 2.9 % IACS |
AWThis page As-welded deposit | Untempered fresh martensite in weld/HAZ — hard and low toughness; post-weld temper at 580–620 °C is normally required. | 800 | 1,000 | 12 | 38 HRC | 2.9 % IACS |
Quenched and tempered, Rm 900–1100 MPa | Highest-strength standard condition for shafts and highly loaded parts where toughness and NACE hardness limits are less critical. | 870 | 980 | 15 | 31 HRC | — |
What is 415-AW?
415-AW is 415 heat treated to AW — untempered fresh martensite in weld/HAZ — hard and low toughness; post-weld temper at 580–620 °C is normally required. 415-AW has a yield strength of 800 MPa (116 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 96% of stainless steel grades. Elongation at break is 12% and the elastic modulus is 200 GPa (29 Msi). 415-AW has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,400°C (2,552 °F). QT780 is the default condition FabDigit quotes; AW is available on request or by drawing note.
Advantages
- High strength — 800 MPa (116 ksi), better than 96% of stainless steel grades
- Conducts heat well — 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades
- High electrical conductivity — 2.9 % IACS, better than 87% of stainless steel grades
Limitations
- Limited ductility — 12%, worse than 95% of stainless steel grades
- Needs corrosion protection — 40/100, worse than 93% of stainless steel grades
- Limited formability — 12/100, worse than 93% of stainless steel grades
- Limited service temperature — 350°C (662 °F), worse than 84% of stainless steel grades
- Low fracture toughness — 70 MPa·√m (63.7 ksi·√in), worse than 83% of stainless steel grades
415-AW properties
Typical room-temperature values for 415-AW; 22 are specific to this condition. Other listed values are 415 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
415-AW has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
415-AW has a yield strength of 800 MPa (116 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 96% of stainless steel grades. Elongation at break is 12% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
415-AW is rated for continuous service to 350°C (662 °F). It conducts heat at 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades. Thermal expansion is 10.5 µm/m·K (5.83 µin/in·°F).
Electrical3
415-AW conducts electricity at 2.9 % IACS, better than 87% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (40/100), worse than 93% of stainless steel grades.
Sustainability4
Producing a kilogram of 415-AW takes about 53 MJ of energy and emits 4.5 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 50%.
Manufacturability8
415-AW's machinability is poor (28/100, worse than 79% of stainless steel grades); weldability very good (70/100); formability not recommended (12/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 415-AW
Is 415 easy to machine?
Machines like a 28 HRC alloy steel — rigid setups, sharp positive-rake carbide, moderate speed and heavy feed to avoid work-hardened glaze; rough in the annealed condition when possible.
Can 415 be welded?
Best-welding martensitic stainless: use matching 410NiMo filler, preheat 100–150 °C on heavy sections, keep interpass <150 °C and post-weld temper 580–620 °C (never 450–550 °C).
Can 415 be formed, bent or molded?
Hot work at 1150–950 °C then air cool and temper; cold forming is limited to gentle bending with generous radii — final quench 950–1050 °C + double temper is preferred.
What surface finishes work on 415?
Passivate per ASTM A967 or electropolish after machining; takes a good mirror polish, and hard-chrome or thermal-spray overlays are common on turbine and shaft wear surfaces.
415 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Clow carbon gives soft, tough lath martensite | ≤ 0.05 | 0.03 |
| Si | ≤ 0.6 | 0.3 |
| Mn | 0.5 – 1 | 0.75 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Cr | 11.5 – 14 | 12.75 |
| Ni | 3.5 – 5.5 | 4.5 |
| Mo | 0.5 – 1 | 0.7 |
| Nlimited in some product specs / EN 1.4313 | ≤ 0.03 | 0.02 |
| Fe | balance | — |
415-AW — frequently asked
What is 415-AW used for?
415-AW is typically used for hydro turbine runners, pump shafts, valve bodies and compressor parts. In short: best-welding martensitic stainless; wrought CA6NM equivalent; tough at 700 MPa yield.
What is the yield strength of 415-AW?
415-AW has a typical yield strength of 800 MPa (116 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 96% of stainless steel grades. Strength varies by condition: see the 7 listed tempers.
Is 415-AW easy to machine?
Not especially — machinability is rated poor (28/100, worse than 79% of stainless steel grades). Machines like a 28 HRC alloy steel — rigid setups, sharp positive-rake carbide, moderate speed and heavy feed to avoid work-hardened glaze; rough in the annealed condition when possible.
Can 415-AW be welded?
Yes — weldability is rated very good (70/100). Best-welding martensitic stainless: use matching 410NiMo filler, preheat 100–150 °C on heavy sections, keep interpass <150 °C and post-weld temper 580–620 °C (never 450–550 °C).
What surface finishes work on 415-AW?
Passivate per ASTM A967 or electropolish after machining; takes a good mirror polish, and hard-chrome or thermal-spray overlays are common on turbine and shaft wear surfaces.
Can 415-AW be formed, bent or molded?
Hot work at 1150–950 °C then air cool and temper; cold forming is limited to gentle bending with generous radii — final quench 950–1050 °C + double temper is preferred.
What is the maximum service temperature of 415-AW?
415-AW is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 415-QT780 and 415-QT650?
QT780 is the default condition — standard commercial condition: best balance of 620 MPa yield, high CVN and weldability — pick this unless a spec says otherwise. QT650: maximum-toughness condition for thick turbine castings/forgings and sour or low-temperature service. Yield strength is 700 MPa in QT780 versus 520 MPa in QT650.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip (UNS S41500) — ASTM International (2023)
- ASTM A182/A182M — Forged or Rolled Alloy and Stainless Steel Pipe Flanges and Fittings (Grade F6NM) — ASTM International (2022)
- ASTM A487/A487M — Steel Castings Suitable for Pressure Service (Grade CA6NM) — ASTM International (2020)
- EN 10088-3 — Stainless steels, Part 3: Semi-finished products, bars, rods (X3CrNiMo13-4, 1.4313) — CEN (2014)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
- Soft martensitic stainless 1.4313 / S41500 datasheet — Böhler / Sandvik / Outokumpu (2022)
- GB/T 1220 ZG06Cr13Ni4Mo (2007)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.