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Steel WC4 vs ZG20CrMo

Steel · grade comparison

Steel WC4 and ZG20CrMo are both steel grades. WC4 is the stronger of the two: yield strength 335 MPa (48.6 ksi) against 285 MPa (41.3 ksi) for ZG20CrMo, about 18% more. WC4 is the more ductile: elongation 24% versus 21% for ZG20CrMo.

WC4Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

WC4 vs ZG20CrMo: properties

WC4ZG20CrMo

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

200 GPa29 Msi
210 GPa30.5 Msi

Shear Modulus

78 GPa11.3 Msi
80 GPa11.6 Msi

Tensile Strength (Ultimate)

545 MPa79 ksi
520 MPa75.4 ksi

Yield Strength (0.2% offset)

335 MPa48.6 ksi
285 MPa41.3 ksi

Elongation at Break

24%
21%

Reduction in Area

50%
38%

Compressive Strength

340 MPa49.3 ksi
285 MPa41.3 ksi

Shear Strength

340 MPa49.3 ksi
330 MPa47.9 ksi

Fatigue Strength (Endurance Limit)

235 MPa34.1 ksi
225 MPa32.6 ksi

Fracture Toughness (K_IC)

120 MPa·√m109 ksi·√in
100 MPa·√m91 ksi·√in

Charpy V-Notch Impact (RT)

48 J35.4 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

163 HB
160 HB

Hardness, Rockwell B

85 HRB
84 HRB

Hardness, Vickers

—
168 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Density

7.83 g/cm³0.28 lb/in³
7.85 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,425°C2,597 °F
1,450°C2,642 °F

Liquidus Temperature

1,500°C2,732 °F
1,510°C2,750 °F

Thermal

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

Specific Heat Capacity

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

Max Service Temperature (continuous)

540°C1,004 °F
510°C950 °F

Min Service Temperature

-29°C-20 °F
-20°C-4 °F

Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

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).

Corrosion Resistance

14 / 100
13 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.62 V

Manufacturability

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

Machinability

58 / 100
55 / 100

Weldability

55 / 100
62 / 100

Formability (cold)

20 / 100
15 / 100

Castability

70 / 100
65 / 100

Brazeability / Solderability

45 / 100
55 / 100

Polishability

45 / 100
60 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 60%

Sustainability

Primary-production footprint per kilogram.

Embodied Water

55 L/kg6.6 gal/lb
60 L/kg7.2 gal/lb

Same in both: Embodied Energy (primary production) 26 MJ/kg11,178 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Typical Recycled Content 75%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

70 kN·m/kg
66 kN·m/kg

Specific Stiffness (E / density)

25.5 MN·m/kg
26.8 MN·m/kg

Modulus of Resilience

281 kJ/m³
193 kJ/m³

Thermal Diffusivity

11.4 mm²/s
11.5 mm²/s

Thermal Shock Resistance Index

9
8

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 scaleWC4ZG20CrMo

Manufacturing and finishing

CapabilityWC4ZG20CrMo
Default condition——
Relative cost$$ Standard$$ Standard
Min. machined wall——
Best machined surface——

Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

WC4 vs ZG20CrMo — frequently asked

Is WC4 stronger than ZG20CrMo?

Yes. WC4 has a typical yield strength of 335 MPa (48.6 ksi) against 285 MPa (41.3 ksi) for ZG20CrMo — about 18% more. Tensile strength is 545 MPa (79 ksi) vs 520 MPa (75.4 ksi).

Which is cheaper, WC4 or ZG20CrMo?

Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which welds better, WC4 or ZG20CrMo?

ZG20CrMo. Its weldability rates good (62/100) against good (55/100) for WC4.

Ready to make it?

Upload a CAD file and FabDigit prices the part in WC4 and ZG20CrMo 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.