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Steel 41CrS4 vs 42CrMo4

Steel · grade comparison

Steel 41CrS4 and 42CrMo4 are both steel grades. 41CrS4 is the stronger of the two: yield strength 720 MPa (104 ksi) against 550 MPa (79.8 ksi) for 42CrMo4, about 31% more; tensile strength follows at 980 MPa (142 ksi) vs 850 MPa (123 ksi). 41CrS4 is harder — 300 HB against 245 HB for 42CrMo4 — which matters for wear surfaces and threads. 42CrMo4 runs hotter in service (400°C vs 300°C continuous). On the shop floor, 42CrMo4 welds better (fair vs poor), 42CrMo4 forms better (fair vs poor), and 41CrS4 sits in a lower cost tier (budget, $) than 42CrMo4 (standard, $$).

41CrS4Choose it when strength drives the design, or when surface hardness matters.

42CrMo4Choose it when the part sees heat, or when it will be welded.

41CrS4 vs 42CrMo4: properties

41CrS442CrMo4

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

980 MPa142 ksi
850 MPa123 ksi

Yield Strength (0.2% offset)

720 MPa104 ksi
550 MPa79.8 ksi

Reduction in Area

45%
40%

Compressive Strength

730 MPa106 ksi
560 MPa81.2 ksi

Shear Strength

590 MPa85.6 ksi
510 MPa74 ksi

Fatigue Strength (Endurance Limit)

450 MPa65.3 ksi
400 MPa58 ksi

Fracture Toughness (K_IC)

65 MPa·√m59.2 ksi·√in
75 MPa·√m68.3 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

300 HB
245 HB

Hardness, Rockwell C

31 HRC
23 HRC

Hardness, Vickers

315 HV
258 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Elongation at Break 14%

Physical

Density and transition temperatures.

Liquidus Temperature

1,490°C2,714 °F
1,495°C2,723 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

44 W/m·K25.4 BTU/hr·ft·°F
42.6 W/m·K24.6 BTU/hr·ft·°F

Specific Heat Capacity

465 J/kg·K0.11 BTU/lb·°F
473 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

12 µm/m·K6.7 µin/in·°F
12.3 µm/m·K6.8 µin/in·°F

Max Service Temperature (continuous)

300°C572 °F
400°C752 °F

Min Service Temperature

-20°C-4 °F
-40°C-40 °F

Same in both: Latent Heat of Fusion 250 J/g107 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

7.7 % IACS
7.8 % IACS

Same in both: Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.65 V
-0.6 V

Same in both: Corrosion Resistance 12 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

55 / 100
50 / 100

Weldability

25 / 100
35 / 100

Formability (cold)

25 / 100
35 / 100

Castability

40 / 100
—

Brazeability / Solderability

55 / 100
50 / 100

Polishability

55 / 100
70 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 55%

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

27 MJ/kg11,608 BTU/lb
30 MJ/kg12,898 BTU/lb

Embodied Carbon (primary production)

2.1 kg CO₂/kg
2.2 kg CO₂/kg

Typical Recycled Content

35%
30%

Same in both: Embodied Water 60 L/kg7.2 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

125 kN·m/kg
108 kN·m/kg

Modulus of Resilience

1,234 kJ/m³
720 kJ/m³

Thermal Diffusivity

12.1 mm²/s
11.5 mm²/s

Thermal Shock Resistance Index

17
14

Same in both: Specific Stiffness (E / density) 26.8 MN·m/kg

Strength versus weight

Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale42CrMo441CrS4

Manufacturing and finishing

Capability41CrS442CrMo4
CNC machining—Yes
Sheet metal—Yes
Default condition—HR
Relative cost$ Budget$$ Standard
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
E-Coating—Yes
HVOF Coating—Yes
Hot-Dip Galvanizing—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

41CrS4 vs 42CrMo4 — frequently asked

Is 41CrS4 stronger than 42CrMo4?

Yes. 41CrS4 has a typical yield strength of 720 MPa (104 ksi) against 550 MPa (79.8 ksi) for 42CrMo4 — about 31% more. Tensile strength is 980 MPa (142 ksi) vs 850 MPa (123 ksi).

Which is cheaper, 41CrS4 or 42CrMo4?

41CrS4 is the lower-cost material: it sits in the budget tier ($) while 42CrMo4 is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, 41CrS4 or 42CrMo4?

41CrS4. Its machinability rates good (55/100) against fair (50/100) for 42CrMo4; for welding the order is 42CrMo4 first (fair, 35/100) then 41CrS4 (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 41CrS4 and 42CrMo4 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.