Stainless Steel 403 · heat-treated state · default condition
Stainless Steel 403 Hardened & Tempered
Properties of the Hardened & Tempered condition, compared with the other 403 tempers.
Standard supply condition for turbine blades and shafts: balanced strength, ductility and steam corrosion resistance.
What is 403 Hardened & Tempered?
403 Hardened & Tempered is 403 heat treated to Hardened & Tempered — standard supply condition for turbine blades and shafts: balanced strength, ductility and steam corrosion resistance. 403 Hardened & Tempered has a yield strength of 655 MPa (95 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 90% of stainless steel grades. Elongation at break is 20% and the elastic modulus is 200 GPa (29 Msi). 403 Hardened & Tempered has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 66% of stainless steel grades. It melts at 1,480°C (2,696 °F).
Advantages
- High electrical conductivity — 3 % IACS, better than 95% of stainless steel grades
- High strength — 655 MPa (95 ksi), better than 90% of stainless steel grades
- Conducts heat well — 24.9 W/m·K (14.4 BTU/hr·ft·°F), better than 88% of stainless steel grades
- Low embodied carbon — 3.8 kg CO₂/kg, better than 77% of stainless steel grades
Limitations
- Low fracture toughness — 70 MPa·√m (63.7 ksi·√in), worse than 87% of stainless steel grades
- Difficult to weld — 35/100, worse than 86% of stainless steel grades
- Needs corrosion protection — 45/100, worse than 85% of stainless steel grades
- Limited ductility — 20%, worse than 79% of stainless steel grades
- Limited formability — 25/100, worse than 79% of stainless steel grades
403 Hardened & Tempered properties
Typical room-temperature values for 403 Hardened & Tempered — 17 properties are specific to this condition; the rest are grade-level values shared by every 403 temper. Each bar shows where the value sits among the stainless steel grades in FabDigit's library — further right is higher.
Physical3
403 Hardened & Tempered has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 66% of stainless steel grades. It melts at 1,480°C (2,696 °F).
Mechanical16
403 Hardened & Tempered has a yield strength of 655 MPa (95 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 90% of stainless steel grades. Elongation at break is 20% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
403 Hardened & Tempered is rated for continuous service to 540°C (1,004 °F). It conducts heat at 24.9 W/m·K (14.4 BTU/hr·ft·°F), better than 88% of stainless steel grades. Thermal expansion is 9.9 µm/m·K (5.5 µin/in·°F).
Electrical3
403 Hardened & Tempered conducts electricity at 3 % IACS, better than 95% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 85% of stainless steel grades.
Sustainability4
Producing a kilogram of 403 Hardened & Tempered takes about 48 MJ of energy and emits 3.8 kg of CO₂ — less than 85% of stainless steel grades. Typical recycled content is 60%.
Manufacturability8
403 Hardened & Tempered's machinability is fair (42/100, better than 79% of stainless steel grades); weldability fair (35/100); formability poor (25/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 403 tempers and conditions
403 is also supplied in 4 other conditions. The full side-by-side table is on the 403 overview.
- Hardened & TemperedDefaultStandard supply condition for turbine blades and shafts: balanced strength, ductility and steam corrosion resistance.655 MPa yield · 26 HRC
- Q&T 205C TemperChoose for wear parts, valve trim and cutting/knife-type components where hardness beats toughness.1,000 MPa yield · 41 HRC
- Q&T 620C TemperChoose when maximum toughness and steam-side stability matter more than strength (long blades, thick sections).585 MPa yield · 22 HRC
- Cold DrawnChoose for straight, size-tolerant bar stock with higher as-supplied strength and good surface finish.550 MPa yield · 200 HB
- AnnealedChoose for maximum machinability, cold forming and bending before heat treatment.290 MPa yield · 155 HB
Working with 403 Hardened & Tempered
Is 403 easy to machine?
Machine in the annealed or high-tempered condition with sharp, rigid tooling, positive rake and generous coolant; expect ~45–55% of AISI 1212 rates and stringy chips below 25 HRC.
Can 403 be welded?
Weldable by GTAW/SMAW with 410/410NiMo filler but requires 200–300 °C preheat, controlled interpass and 650–750 °C post-weld temper to avoid hard, crack-prone martensite in the HAZ.
Can 403 be formed, bent or molded?
Cold-form only in the annealed state with generous bend radii (≥2t); hot work 1150–1200 °C, stop above ~900 °C, then slow-cool or anneal to avoid quench cracking.
What surface finishes work on 403?
Passivate (ASTM A967 nitric or citric) after machining; takes a fine mechanical or electropolished finish, and can be hard chrome plated or nitrided for wear service — do not anodize.
403 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 |
|---|---|---|
| C | ≤ 0.15 | 0.12 |
| Mn | ≤ 1 | 0.5 |
| Silower than 410 — key distinction of 403 | ≤ 0.5 | 0.3 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Cr | 11.5 – 13 | 12.2 |
| Nirestricted in turbine-quality practice | ≤ 0.5 | 0.3 |
| Fe | balance | — |
403 Hardened & Tempered — frequently asked
What is 403 Hardened & Tempered used for?
403 Hardened & Tempered is typically used for steam turbine blades, axial compressor blades, turbine blade forgings and roots, valve bodies and valve trim, pump shafts and high-temperature bolting. In short: hardenable martensitic forging.
What is the yield strength of 403 Hardened & Tempered?
403 Hardened & Tempered has a typical yield strength of 655 MPa (95 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 90% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 403 Hardened & Tempered easy to machine?
Not especially — machinability is rated fair (42/100, better than 79% of stainless steel grades). Machine in the annealed or high-tempered condition with sharp, rigid tooling, positive rake and generous coolant; expect ~45–55% of AISI 1212 rates and stringy chips below 25 HRC.
Can 403 Hardened & Tempered be welded?
With care — weldability is rated fair (35/100). Weldable by GTAW/SMAW with 410/410NiMo filler but requires 200–300 °C preheat, controlled interpass and 650–750 °C post-weld temper to avoid hard, crack-prone martensite in the HAZ.
What surface finishes work on 403 Hardened & Tempered?
Passivate (ASTM A967 nitric or citric) after machining; takes a fine mechanical or electropolished finish, and can be hard chrome plated or nitrided for wear service — do not anodize.
Can 403 Hardened & Tempered be formed, bent or molded?
Cold-form only in the annealed state with generous bend radii (≥2t); hot work 1150–1200 °C, stop above ~900 °C, then slow-cool or anneal to avoid quench cracking.
What is the maximum service temperature of 403 Hardened & Tempered?
403 Hardened & Tempered is rated for continuous use to about 540°C (1,004 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 403 Hardened & Tempered?
Yes — 403 Hardened & Tempered is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A276/A276M Stainless Steel Bars and Shapes — ASTM (2023)
- ASTM A484/A484M General Requirements for Stainless Steel Bars, Billets and Forgings — ASTM (2022)
- EN 10088-1 Stainless steels — List of stainless steels (X6Cr13, 1.4000) — CEN (2014)
- ASM Specialty Handbook: Stainless Steels — ASM International (1994)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- GB/T 1220 (1Cr12 / 12Cr13 ) — SAC (2007)
- SMM / Mysteel (2025)
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.