Stainless Steel 422
AISI/SAE 422 · UNS S42200
422 (S42200) is a Cr-Mo-W-V martensitic stainless engineered for high strength and creep resistance up to about 600 °C, supplied annealed, normalized-and-tempered, hot rolled or hardened and tempered to 38–42 HRC.
Values for the Hardened & Tempered condition
422 tempers and conditions
422 is supplied in 5 conditions, soft to hard. Hardened & Tempered is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
full anneal (~840–900 °C, slow cool) | Softest supply condition for machining, straightening or before hardening; not a service condition for high-temperature parts. | 590 | 790 | 20 | 22 HRC | — |
Normalized and tempered | Air-cooled from austenitizing then tempered; used for heavy forgings and sections where oil quenching risks cracking. | 790 | 960 | 17 | 32 HRC | 2.9 % IACS |
Hardened & TemperedDefault oil quench from ~1040 °C, temper 620–650 °C (≈300–340 HB) | Standard turbine-blade / high-temperature bolting condition: best balance of strength, creep resistance and toughness to 650 °C. | 860 | 1,030 | 16 | 32 HRC | 24 W/m·K |
Hot Rolled / as-forged (untempered mill condition) | Mill stock supplied for subsequent forging and heat treatment; hard, notch-sensitive and not for direct service use. | 900 | 1,150 | 12 | 37 HRC | 2.8 % IACS |
Hardened and tempered low | Choose when maximum room-temperature strength and wear resistance matter more than toughness or long-term 600 °C stability. | 1,030 | 1,240 | 13 | 40 HRC | — |
What is 422?
422 (S42200) is a Cr-Mo-W-V martensitic stainless engineered for high strength and creep resistance up to about 600 °C, supplied annealed, normalized-and-tempered, hot rolled or hardened and tempered to 38–42 HRC. In the default condition it provides 860 MPa yield, 1030 MPa tensile, 16% elongation, 302 HB (32 HRC) and a 213 GPa modulus at 7.8 g/cm³, which suits steam turbine blading and elevated-temperature bolting up to a 650 °C service limit. Machinability (35) and formability (20) are low, and welding demands high preheat plus a post-weld temper. 410 or 410NiMo is the cheaper choice below roughly 500 °C. 422 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,425°C (2,597 °F). 422 has a yield strength of 860 MPa (125 ksi) and a tensile strength of 1,030 MPa (149 ksi) — stronger than 98% of stainless steel grades. Elongation at break is 16% and the elastic modulus is 213 GPa (30.9 Msi).
What is 422 used for?
- Steam turbine blades
- High-temperature bolting and studs
- Valve bodies and stems for steam service
- Turbine rotor and disc forgings
- Pump shafts for hot service
- Compressor components
- Hot-service fasteners
Advantages
- High strength — 860 MPa (125 ksi), better than 98% of stainless steel grades
- Low embodied carbon — 3.5 kg CO₂/kg, better than 88% of stainless steel grades
- Conducts heat well — 24 W/m·K (13.9 BTU/hr·ft·°F), better than 81% of stainless steel grades
Limitations
- Limited ductility — 16%, worse than 88% of stainless steel grades
- Difficult to weld — 30/100, worse than 88% of stainless steel grades
- Limited formability — 20/100, worse than 86% of stainless steel grades
- Needs corrosion protection — 45/100, worse than 85% of stainless steel grades
- Low fracture toughness — 75 MPa·√m (68.3 ksi·√in), worse than 81% of stainless steel grades
422 properties
Typical room-temperature values for 422-Hardened & Tempered; bars are the position among stainless steel grades.
Physical3
422 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,425°C (2,597 °F).
Mechanical15
422 has a yield strength of 860 MPa (125 ksi) and a tensile strength of 1,030 MPa (149 ksi) — stronger than 98% of stainless steel grades. Elongation at break is 16% and the elastic modulus is 213 GPa (30.9 Msi).
Thermal5
422 is rated for continuous service to 650°C (1,202 °F). It conducts heat at 24 W/m·K (13.9 BTU/hr·ft·°F), better than 81% of stainless steel grades. Thermal expansion is 11.2 µm/m·K (6.22 µin/in·°F).
Electrical2
422 has an electrical resistivity of 6×10⁻⁷ Ω·m.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 85% of stainless steel grades.
Sustainability4
Producing a kilogram of 422 takes about 53 MJ of energy and emits 3.5 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 40%.
Manufacturability7
422's machinability is fair (35/100, better than 51% of stainless steel grades); weldability poor (30/100); formability poor (20/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. 422 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 422
Is 422 easy to machine?
Machine in the annealed or high-temper condition with rigid setups, sharp carbide tooling, low speed (~25–45 m/min) and heavy feeds; the W/V carbides are abrasive and work-hardening is significant.
Can 422 be welded?
Weldable only with 400 °C-class preheat, matching or 410NiMo filler, interpass control and mandatory post-weld temper at ~700 °C — otherwise cold cracking of the martensitic HAZ.
Can 422 be formed, bent or molded?
Hot work at 1100–1150 °C with slow cooling and immediate annealing; cold forming is essentially limited to gentle straightening.
Manufacturability
The process limits FabDigit applies to 422. Every 422 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Fair35 / 100 |
|---|---|
| ISO material group | M.1 |
| Cutting speed (rough / finish) | 150 / 180 m/min |
| Minimum wall | 0.8 mm |
| Minimum internal radius | 1.5 mm |
| Drill depth limit | 4× diameter |
| Best surface (machined / polished) | Ra 1.6 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Fair20 / 100 |
|---|---|
| Weldability | Poor30 / 100 |
422 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 | 0.2 – 0.25 | 0.22 |
| Mn | 0.5 – 1 | 0.75 |
| Si | ≤ 0.5 | 0.35 |
| P | ≤ 0.03 | |
| S | ≤ 0.03 | |
| Cr | 11 – 12.5 | 11.75 |
| Ni | 0.5 – 1 | 0.75 |
| Mo | 0.9 – 1.25 | 1 |
| W | 0.9 – 1.25 | 1 |
| V | 0.2 – 0.3 | 0.25 |
| Fe | balance |
What surface finishes work on 422?
Passivate after machining, or apply steam/black-oxide, chromizing or aluminizing for high-temperature oxidation; takes a good mechanical polish but never anodizes.
Surface treatments FabDigit runs on stainless steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
Organic Coating
CVD Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel 422 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S42200
- Also called
- Alloy 616
How much does 422 cost?
422 is a premium-cost stainless steel ($$$), pricier than about 58% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
422 — frequently asked
What is 422 used for?
422 is typically used for steam turbine blades, high-temperature bolting and studs, valve bodies and stems for steam service, turbine rotor and disc forgings, pump shafts for hot service and compressor components. In short: high-temp martensitic forging.
What is the yield strength of 422?
422 has a typical yield strength of 860 MPa (125 ksi) and a tensile strength of 1,030 MPa (149 ksi) — stronger than 98% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 422 easy to machine?
Not especially — machinability is rated fair (35/100, better than 51% of stainless steel grades). Machine in the annealed or high-temper condition with rigid setups, sharp carbide tooling, low speed (~25–45 m/min) and heavy feeds; the W/V carbides are abrasive and work-hardening is significant.
Can 422 be welded?
Not readily — weldability is rated poor (30/100). Weldable only with 400 °C-class preheat, matching or 410NiMo filler, interpass control and mandatory post-weld temper at ~700 °C — otherwise cold cracking of the martensitic HAZ.
What surface finishes work on 422?
Passivate after machining, or apply steam/black-oxide, chromizing or aluminizing for high-temperature oxidation; takes a good mechanical polish but never anodizes.
Can 422 be formed, bent or molded?
Hot work at 1100–1150 °C with slow cooling and immediate annealing; cold forming is essentially limited to gentle straightening.
What is the maximum service temperature of 422?
422 is rated for continuous use to about 650°C (1,202 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 422 cost?
422 is a premium-cost stainless steel ($$$), pricier than about 58% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in 422?
Yes — 422 is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A565/A565M — Martensitic Stainless Steel Bars for High-Temperature Service (Grade 616 / S42200) — ASTM International (2019)
- ASTM A276/A479 — Stainless Steel Bars and Shapes — ASTM International (2022)
- ASM Specialty Handbook: Stainless Steels — ASM International (1994)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Unified Numbering System for Metals and Alloys (UNS S42200) — SAE/ASTM (2017)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.