Stainless Steel 4Cr13
EN 4Cr13 · UNS S42000
4Cr13 (S42000) is a higher-carbon Chinese-standard martensitic stainless in the AISI 420/440A range, giving greater attainable hardness than 3Cr13 after quench and temper.
Reference datasheet — 4Cr13 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the Annealed condition
4Cr13 tempers and conditions
4Cr13 is supplied in 6 conditions, soft to hard. Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault soft annealed bar, plate and sheet | Standard stocked delivery condition for machining, blanking and subsequent hardening. | 380 | 700 | 22 | 217 HB | — |
Cold drawn | Choose for close-tolerance shafting and screw-machine parts that will not be hardened. | 600 | 790 | 12 | 245 HB | — |
Q&T 600–680 °C | Toughest condition — for shafts, pump/valve stems and fasteners needing strength plus impact resistance rather than wear resistance. | 800 | 1,000 | 15 | 31 HRC | — |
Q&T 300 °C | Slightly tougher mould / valve-trim condition where some impact loading is expected. | 1,350 | 1,650 | 6 | 49 HRC | — |
Q&T 200 °C | Standard cutlery / shear-blade / bearing condition — maximum wear resistance with minimum toughness loss. | 1,450 | 1,750 | 4 | 52 HRC | — |
Hardened | Maximum as-quenched hardness; brittle and must normally be tempered before service. | 1,950 | 1 | 56 HRC | — |
What is 4Cr13?
4Cr13 (S42000) is a higher-carbon Chinese-standard martensitic stainless in the AISI 420/440A range, giving greater attainable hardness than 3Cr13 after quench and temper. It is used for cutting tools, medical instruments and bearing rings, and is on file annealed, cold-drawn, hardened and in QT200, QT300 and QT600 tempers; the annealed default gives 380 MPa yield, 700 MPa tensile, 22 % elongation and 217 HB, with service to 500 °C. Weldability (30), formability (35) and corrosion resistance (42) are all limited. Use 3Cr13 where forming and joining matter more than edge hardness. 4Cr13 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,425°C (2,597 °F). 4Cr13 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 52% of stainless steel grades. Elongation at break is 22% and the elastic modulus is 200 GPa (29 Msi).
What is 4Cr13 used for?
- cutting tools
- medical instruments
- bearing rings
Advantages
- High electrical conductivity — 3.1 % IACS, better than 99% of stainless steel grades
- Polishes to a fine finish — 85/100, better than 97% of stainless steel grades
- Conducts heat well — 24.9 W/m·K (14.4 BTU/hr·ft·°F), better than 87% of stainless steel grades
- Easy to machine — 45/100, better than 84% of stainless steel grades
- Low embodied carbon — 3.6 kg CO₂/kg, better than 83% of stainless steel grades
Limitations
- Needs corrosion protection — 42/100, worse than 90% of stainless steel grades
- Low fracture toughness — 60 MPa·√m (54.6 ksi·√in), worse than 88% of stainless steel grades
- Difficult to weld — 30/100, worse than 88% of stainless steel grades
- Limited ductility — 22%, worse than 75% of stainless steel grades
4Cr13 properties
Typical room-temperature values for 4Cr13-Annealed; bars are the position among stainless steel grades.
Physical3
4Cr13 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
4Cr13 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 52% of stainless steel grades. Elongation at break is 22% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
4Cr13 is rated for continuous service to 500°C (932 °F). It conducts heat at 24.9 W/m·K (14.4 BTU/hr·ft·°F), better than 87% of stainless steel grades. Thermal expansion is 10.3 µm/m·K (5.72 µin/in·°F).
Electrical3
4Cr13 conducts electricity at 3.1 % IACS, better than 99% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (42/100), worse than 90% of stainless steel grades.
Sustainability4
Producing a kilogram of 4Cr13 takes about 46 MJ of energy and emits 3.6 kg of CO₂ — less than 88% of stainless steel grades. Typical recycled content is 55%.
Manufacturability6
4Cr13's machinability is fair (45/100, better than 84% of stainless steel grades); weldability poor (30/100); formability fair (35/100).
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. 4Cr13 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 4Cr13
Is 4Cr13 easy to machine?
Machine in the annealed state with sharp, rigid tooling, low speeds and flood coolant; hardened >45 HRC parts need carbide/CBN or grinding and EDM.
Can 4Cr13 be welded?
Poor weldability — preheat 200–300 °C, use matching or austenitic (309/310) filler and temper immediately after welding to avoid HAZ cracking.
Can 4Cr13 be formed, bent or molded?
Only light cold forming in the annealed condition (bending radii ≥2t); hot work at 1100–850 °C and always slow-cool or anneal after hot forging.
4Cr13 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 |
|---|---|---|
| CGB/T 1220 40Cr13 | 0.36 – 0.45 | 0.4 |
| Si | ≤ 0.6 | 0.35 |
| Mn | ≤ 0.8 | 0.45 |
| P | ≤ 0.04 | |
| S | ≤ 0.03 | |
| Cr | 12 – 14 | 13 |
| Niresidual | ≤ 0.6 | |
| Fe | balance |
What surface finishes work on 4Cr13?
Takes an excellent mirror polish (mould cavities); passivate in nitric or citric acid after grinding/polishing, and hard chrome or nitriding can be added for extra wear life.
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).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel 4Cr13 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S42000
- Other
- 420C
How much does 4Cr13 cost?
4Cr13 is a standard-cost stainless steel ($$), cheaper than about 71% 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.
4Cr13 — frequently asked
What is 4Cr13 used for?
4Cr13 is typically used for cutting tools, medical instruments and bearing rings. In short: harder than 3Cr13; mirror-polishing mould grade; low-cost cutlery stainless.
What is the yield strength of 4Cr13?
4Cr13 has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 52% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is 4Cr13 easy to machine?
Reasonably — machinability is rated fair (45/100, better than 84% of stainless steel grades). Machine in the annealed state with sharp, rigid tooling, low speeds and flood coolant; hardened >45 HRC parts need carbide/CBN or grinding and EDM.
Can 4Cr13 be welded?
Not readily — weldability is rated poor (30/100). Poor weldability — preheat 200–300 °C, use matching or austenitic (309/310) filler and temper immediately after welding to avoid HAZ cracking.
What surface finishes work on 4Cr13?
Takes an excellent mirror polish (mould cavities); passivate in nitric or citric acid after grinding/polishing, and hard chrome or nitriding can be added for extra wear life.
Can 4Cr13 be formed, bent or molded?
Only light cold forming in the annealed condition (bending radii ≥2t); hot work at 1100–850 °C and always slow-cool or anneal after hot forging.
What is the maximum service temperature of 4Cr13?
4Cr13 is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 4Cr13 Annealed and 4Cr13-QT200?
Annealed is the default condition — standard stocked delivery condition for machining, blanking and subsequent hardening. QT200: standard cutlery / shear-blade / bearing condition — maximum wear resistance with minimum toughness loss. Yield strength is 380 MPa in Annealed versus 1,450 MPa in QT200.
How much does 4Cr13 cost?
4Cr13 is a standard-cost stainless steel ($$), cheaper than about 71% 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.
Sources
- GB/T 1220 (40Cr13/4Cr13) — SAC (2007)
- ASTM A276/A276M Stainless Steel Bars and Shapes (Type 420, UNS S42000) — ASTM (2017)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
- Type 420 Stainless Steel product data sheet — AK Steel / Cleveland-Cliffs (2018)
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.