Steel 20MoCrS4
EN 20MoCrS4
20MoCrS4 (1.7323) is the resulfurized version of 20MoCr4, a Mo-Cr case-hardening steel to EN 10084 optimized for automatic-lathe machining of small-to-medium carburized parts.
Reference datasheet — 20MoCrS4 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 +AC+C condition
20MoCrS4 tempers and conditions
20MoCrS4 is supplied in 9 conditions, soft to hard. +AC+C is the default FabDigit quotes; the values on this page are for it.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Softest supply state — use for deep cold forming/cold extrusion of blanks or for heavy drilling/broaching before carburizing. | 330 | 540 | 23 | 165 HB | — |
Treated for shearability | Choose when bar is cold-sheared into slugs for cold/warm forging before carburizing. | 350 | 560 | 20 | 170 HB | 8 % IACS |
Treated to ferrite-pearlite structure and hardness range | Standard hot-rolled bar condition giving a uniform F-P microstructure and predictable, repeatable turning/hobbing behaviour before carburizing. | 400 | 620 | 18 | 178 HB | — |
Treated to a specified hardness range | Pick when only a hardness window (not the microstructure) must be guaranteed for stable machining. | 410 | 600 | 18 | 10 HRC | 8 % IACS |
Hot rolled | Cheapest hot-rolled bar supply when the customer normalizes or anneals in-house before machining. | 420 | 660 | 17 | 12 HRC | 8 % IACS |
Guaranteed hardenability (Jominy band) / hardened condition | Order +H when the Jominy end-quench band must be certified so case/core hardness after carburizing-quenching is reproducible on high-volume gear and shaft parts. | 430 | 620 | 17 | 44 HRC | 8 % IACS |
+AC+CDefault Spheroidize annealed and cold drawn | The workhorse condition for automatic-lathe/Swiss turning: tight tolerance bright bar with good chip control and enough strength for handling before carburizing. | 500 | 600 | 10 | 185 HB | — |
Cold drawn | Cold-drawn bright bar without prior spheroidizing — cheaper, slightly stronger and harder than +AC+C but less suited to cold heading. | 570 | 680 | 8 | 14 HRC | 8 % IACS |
Case hardened | Final in-service condition of the finished part: hard wear-resistant case over a tough Mo-Cr alloyed core. | 750 | 1,050 | 10 | 60 HRC | — |
What is 20MoCrS4?
20MoCrS4 (1.7323) is the resulfurized version of 20MoCr4, a Mo-Cr case-hardening steel to EN 10084 optimized for automatic-lathe machining of small-to-medium carburized parts. It trades some toughness for machinability (score 66), with values of about 500 MPa yield, 600 MPa tensile, 10 % elongation and 185 HB in the delivered condition and service to roughly 200 °C. Bar and cold-drawn bar dominate the supply. Weldability is poor (score 26) and the sulfides reduce transverse ductility, so specify sulfur-free 20MoCr4 where welding or heavy transverse forming is planned. 20MoCrS4 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). 20MoCrS4 has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 63% of steel grades. Elongation at break is 10% and the elastic modulus is 210 GPa (30.5 Msi).
What is 20MoCrS4 used for?
- mass-produced carburized gears
- shafts on CNC turning centers
- small automotive driveline parts
Advantages
- Easy to machine — 66/100, better than 95% of steel grades
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
Limitations
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
- Limited ductility — 10%, worse than 91% of steel grades
- Low fracture toughness — 65 MPa·√m (59.2 ksi·√in), worse than 75% of steel grades
20MoCrS4 properties
Typical room-temperature values for 20MoCrS4-+AC+C; bars are the position among steel grades.
Physical3
20MoCrS4 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
20MoCrS4 has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 63% of steel grades. Elongation at break is 10% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
20MoCrS4 is rated for continuous service to 200°C (392 °F). It conducts heat at 42 W/m·K (24.3 BTU/hr·ft·°F), worse than 56% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical3
20MoCrS4 conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 20MoCrS4 takes about 26 MJ of energy and emits 1.9 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 30%.
Manufacturability8
20MoCrS4's machinability is good (66/100, better than 95% of steel grades); weldability poor (26/100); formability poor (32/100).
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 steel family
Yield strength against density for every steel grade FabDigit runs. 20MoCrS4 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 20MoCrS4
Is 20MoCrS4 easy to machine?
Excellent for CNC/cam automatics in +AC+C: MnS inclusions break chips; carbide inserts at 150–220 m/min turning, coolant optional — expect ~15–25 % better tool life than sulfur-free 20MoCr4.
Can 20MoCrS4 be welded?
Poor: CEV ≈ 0.5–0.6 plus 0.02–0.04 % S causes hot-cracking risk; if unavoidable use low-hydrogen consumables, 200–300 °C preheat, immediate stress relief, and never weld carburized surfaces.
Can 20MoCrS4 be formed, bent or molded?
Cold heading/extrusion only from the +AC (spheroidized) state with phosphate-soap lubrication; hot forge 1100–850 °C then anneal, avoid heavy transverse cold bending because sulfides reduce transverse ductility.
20MoCrS4 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 | 0.17 – 0.23 | 0.2 |
| Simax only | ≤ 0.4 | 0.25 |
| Mn | 0.6 – 0.9 | 0.75 |
| Pmax only | ≤ 0.03 | 0.02 |
| Sdeliberately added for machinability (resulfurized) | 0.02 – 0.04 | 0.03 |
| Cr | 0.3 – 0.6 | 0.45 |
| Mo | 0.4 – 0.5 | 0.45 |
| Fe | balance |
What surface finishes work on 20MoCrS4?
Not anodizable; protect with phosphating + oil, black oxide, or Zn/Zn-Ni plating (bake 190–220 °C for hydrogen de-embrittlement after case hardening); ground and honed case surfaces polish to a functional but not mirror finish.
Surface treatments FabDigit runs on 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).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel 20MoCrS4 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- 1.732310084
- Similar grades
- 20MoCr4
How much does 20MoCrS4 cost?
20MoCrS4 is a budget-cost steel ($), cheaper than about 90% 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.
20MoCrS4 — frequently asked
What is 20MoCrS4 used for?
20MoCrS4 is typically used for mass-produced carburized gears, shafts on CNC turning centers and small automotive driveline parts. In short: free-machining 20MoCr4; 15–25 % longer tool life; poor weldability.
What is the yield strength of 20MoCrS4?
20MoCrS4 has a typical yield strength of 500 MPa (72.5 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 63% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is 20MoCrS4 easy to machine?
Reasonably — machinability is rated good (66/100, better than 95% of steel grades). Excellent for CNC/cam automatics in +AC+C: MnS inclusions break chips; carbide inserts at 150–220 m/min turning, coolant optional — expect ~15–25 % better tool life than sulfur-free 20MoCr4.
Can 20MoCrS4 be welded?
Not readily — weldability is rated poor (26/100). Poor: CEV ≈ 0.5–0.6 plus 0.02–0.04 % S causes hot-cracking risk; if unavoidable use low-hydrogen consumables, 200–300 °C preheat, immediate stress relief, and never weld carburized surfaces.
What surface finishes work on 20MoCrS4?
Not anodizable; protect with phosphating + oil, black oxide, or Zn/Zn-Ni plating (bake 190–220 °C for hydrogen de-embrittlement after case hardening); ground and honed case surfaces polish to a functional but not mirror finish.
Can 20MoCrS4 be formed, bent or molded?
Cold heading/extrusion only from the +AC (spheroidized) state with phosphate-soap lubrication; hot forge 1100–850 °C then anneal, avoid heavy transverse cold bending because sulfides reduce transverse ductility.
What is the maximum service temperature of 20MoCrS4?
20MoCrS4 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 20MoCrS4 +AC+C and 20MoCrS4 CHQT?
+AC+C is the default condition — the workhorse condition for automatic-lathe/Swiss turning: tight tolerance bright bar with good chip control and enough strength for handling before carburizing. CHQT: final in-service condition of the finished part: hard wear-resistant case over a tough Mo-Cr alloyed core. Yield strength is 500 MPa in +AC+C versus 750 MPa in CHQT.
How much does 20MoCrS4 cost?
20MoCrS4 is a budget-cost steel ($), cheaper than about 90% 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
- EN 10084 — Case hardening steels: technical delivery conditions — CEN (2008)
- EN 10277 — Bright steel products: technical delivery conditions — CEN (2018)
- Stahlschlüssel / Key to Steel — Verlag Stahlschlüssel Wegst (2019)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Case-hardening steel 20MoCr4 / 20MoCrS4 data sheet — Deutsche Edelstahlwerke / Ovako (2020)
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.