Stainless Steel 420V
AISI/SAE 420V
420V (CPM 420V, now sold as CPM S90V) is a powder-metallurgy martensitic stainless tool steel with about 2.3% carbon and 9% vanadium, hardenable to 58–61 HRC.
Values for the Annealed condition
420V tempers and conditions
420V is supplied in 3 conditions, soft to hard. Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault soft annealed bar/plate as supplied by the mill | Stock condition for rough machining, grinding and blanking before hardening. | 600 | 900 | 8 | 25 HRC | 2.8 % IACS |
Hardened & High-Tempered | Choose when parts must be stress-relieved for dimensional stability, nitrided or coated (PVD) at elevated temperature; slightly lower hardness and corrosion resistance. | 1,750 | 1,950 | 1.5 | 56 HRC | 2.5 % IACS |
austenitise ~1120 °C, quench, temper ~205 °C (58–61 HRC) | Standard service condition for knife blades and wear parts: maximum hardness, wear resistance and best corrosion resistance. | 1,900 | 2,100 | 1 | 59 HRC | — |
What is 420V?
420V (CPM 420V, now sold as CPM S90V) is a powder-metallurgy martensitic stainless tool steel with about 2.3% carbon and 9% vanadium, hardenable to 58–61 HRC. The dense dispersion of fine MC-type vanadium carbides gives extreme wear resistance, while 14% chromium provides moderate stainless corrosion resistance; it is bought as blade stock, bar and plate for cutting and wear parts. Limits are low toughness, very difficult machining and grinding (CBN or diamond wheels), essentially no weldability, and a price far above conventional stainless. CPM S30V is the tougher, easier-to-process alternative. 420V has a density of 7.39 g/cm³ (0.267 lb/in³), lighter than 100% of stainless steel grades. It melts at 1,400°C (2,552 °F). 420V has a yield strength of 600 MPa (87 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 86% of stainless steel grades. Elongation at break is 8% and the elastic modulus is 210 GPa (30.5 Msi).
What is 420V used for?
- Custom knife blades
- Cutlery blades
- Plastic pelletizing and granulating knives
- Slitting knives for film and paper
- Wear-resistant mould and die inserts
- Corrosion-resistant bearing components
- Industrial cutting blades
Advantages
- High strength — 600 MPa (87 ksi), better than 86% of stainless steel grades
- High electrical conductivity — 2.8 % IACS, better than 79% of stainless steel grades
Limitations
- Difficult to machine — 15/100, worse than 100% of stainless steel grades
- Limited ductility — 8%, worse than 99% of stainless steel grades
- Low fracture toughness — 28 MPa·√m (25.5 ksi·√in), worse than 99% of stainless steel grades
- Difficult to weld — 12/100, worse than 99% of stainless steel grades
- Limited formability — 12/100, worse than 93% of stainless steel grades
420V properties
Typical room-temperature values for 420V-Annealed; bars are the position among stainless steel grades.
Physical3
420V has a density of 7.39 g/cm³ (0.267 lb/in³), lighter than 100% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical17
420V has a yield strength of 600 MPa (87 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 86% of stainless steel grades. Elongation at break is 8% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
420V is rated for continuous service to 400°C (752 °F). It conducts heat at 20 W/m·K (11.6 BTU/hr·ft·°F), better than 74% of stainless steel grades. Thermal expansion is 10.4 µm/m·K (5.78 µin/in·°F).
Electrical3
420V conducts electricity at 2.8 % IACS, better than 79% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 85% of stainless steel grades.
Sustainability4
Producing a kilogram of 420V takes about 80 MJ of energy and emits 6.5 kg of CO₂ — more than 89% of stainless steel grades. Typical recycled content is 25%.
Manufacturability7
420V's machinability is poor (15/100, worse than 100% of stainless steel grades); weldability not recommended (12/100); formability not recommended (12/100).
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. 420V is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 420V
Is 420V easy to machine?
Machine only in the annealed state with rigid setups, positive-rake carbide or CBN tooling, low speeds and heavy coolant; grinding requires CBN or diamond wheels because 9% V carbides destroy alumina wheels.
Can 420V be welded?
Not recommended — high carbon, air-hardening matrix cracks readily; if unavoidable, preheat ~300 °C, use matched PM/tool-steel filler and temper immediately.
Can 420V be formed, bent or molded?
No practical cold forming; hot work 1040–1120 °C with slow controlled cooling, and always follow with a full soft anneal before machining.
Manufacturability
The process limits FabDigit applies to 420V. Every 420V part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Fair15 / 100 |
|---|---|
| ISO material group | M.4 |
| Cutting speed (rough / finish) | 140 / 170 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 |
420V 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 |
|---|---|---|
| Cforms abundant vanadium MC carbides | 2.15 – 2.45 | 2.3 |
| Cr | 13.5 – 14.5 | 14 |
| Vprimary wear-resistance carbide former | 8.5 – 9.5 | 9 |
| Mo | 0.8 – 1.2 | 1 |
| Mn | ≤ 0.6 | 0.5 |
| Si | ≤ 0.6 | 0.5 |
| Fe | balance |
What surface finishes work on 420V?
Hardened and low-tempered surfaces take a fine mirror polish; passivate for best stain resistance, or apply PVD/DLC (use the high-temper condition if coating temperature exceeds the temper temperature).
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
How much does 420V cost?
420V is a specialty-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.
420V — frequently asked
What is 420V used for?
420V is typically used for custom knife blades, cutlery blades, plastic pelletizing and granulating knives, slitting knives for film and paper, wear-resistant mould and die inserts and corrosion-resistant bearing components. In short: extreme wear resistant stainless.
What is the yield strength of 420V?
420V has a typical yield strength of 600 MPa (87 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 86% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 420V easy to machine?
Not especially — machinability is rated poor (15/100, worse than 100% of stainless steel grades). Machine only in the annealed state with rigid setups, positive-rake carbide or CBN tooling, low speeds and heavy coolant; grinding requires CBN or diamond wheels because 9% V carbides destroy alumina wheels.
Can 420V be welded?
Not readily — weldability is rated not recommended (12/100). Not recommended — high carbon, air-hardening matrix cracks readily; if unavoidable, preheat ~300 °C, use matched PM/tool-steel filler and temper immediately.
What surface finishes work on 420V?
Hardened and low-tempered surfaces take a fine mirror polish; passivate for best stain resistance, or apply PVD/DLC (use the high-temper condition if coating temperature exceeds the temper temperature).
Can 420V be formed, bent or molded?
No practical cold forming; hot work 1040–1120 °C with slow controlled cooling, and always follow with a full soft anneal before machining.
What is the maximum service temperature of 420V?
420V is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 420V cost?
420V is a specialty-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 420V?
Yes — 420V is available for CNC machining; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- CPM S90V (formerly CPM 420V) Data Sheet — Crucible Industries (2015)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol. 7: Powder Metallurgy — ASM International (2015)
- ASTM A600 / A681 (tool steel general requirements, for reference) — ASTM (2016)
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.