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Steel 42CrMo4 Annealed vs 42CrMo4 Q&T

Steel · 42CrMo4 temper comparison

42CrMo4 Annealed and 42CrMo4 Q&T are two conditions of the same steel grade, 42CrMo4: Annealed versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 42CrMo4 Q&T is the stronger of the two: yield strength 850 MPa (123 ksi) against 415 MPa (60.2 ksi) for 42CrMo4 Annealed, about 105% more; tensile strength follows at 1,000 MPa (145 ksi) vs 655 MPa (95 ksi). In exchange, 42CrMo4 Annealed is the more ductile: elongation 20% versus 14% for 42CrMo4 Q&T, and 42CrMo4 Q&T is harder (300 HB vs 197 HB). On the shop floor, 42CrMo4 Annealed machines more easily (good vs fair).

42CrMo4 AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

42CrMo4 Q&TChoose it when strength drives the design.

42CrMo4 Annealed vs 42CrMo4 Q&T: properties

42CrMo4 Annealed42CrMo4 Q&T

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

655 MPa95 ksi
1,000 MPa145 ksi

Yield Strength (0.2% offset)

415 MPa60.2 ksi
850 MPa123 ksi

Elongation at Break

20%
14%

Reduction in Area

50%
45%

Compressive Strength

560 MPa81.2 ksi
870 MPa126 ksi

Shear Strength

400 MPa58 ksi
620 MPa89.9 ksi

Fatigue Strength (Endurance Limit)

340 MPa49.3 ksi
500 MPa72.5 ksi

Fracture Toughness (K_IC)

75 MPa·√m68.3 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

197 HB
300 HB

Hardness, Rockwell C

13 HRC
31 HRC

Hardness, Vickers

258 HV
315 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

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,495°C2,723 °F

Thermal

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

Max Service Temperature (continuous)

400°C752 °F
425°C797 °F

Min Service Temperature

-40°C-40 °F
-50°C-58 °F

Same in both: Thermal Conductivity 42.6 W/m·K24.6 BTU/hr·ft·°F · Specific Heat Capacity 473 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

60 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
50%

Weldability

40 / 100
35 / 100

Formability (cold)

45 / 100
35 / 100

Same in both: Brazeability / Solderability 50 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 30%

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 scale42CrMo4

42CrMo4 Annealed vs 42CrMo4 Q&T — frequently asked

Is 42CrMo4 Q&T stronger than 42CrMo4 Annealed?

Yes. 42CrMo4 Q&T has a typical yield strength of 850 MPa (123 ksi) against 415 MPa (60.2 ksi) for 42CrMo4 Annealed — about 105% more. Tensile strength is 1,000 MPa (145 ksi) vs 655 MPa (95 ksi).

Which condition does FabDigit quote by default, Annealed or Q&T?

HR is the default 42CrMo4 condition in the FabDigit quote flow (neither Annealed nor Q&T). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which is easier to machine, 42CrMo4 Annealed or 42CrMo4 Q&T?

42CrMo4 Annealed. Its machinability rates good (60/100) against fair (45/100) for 42CrMo4 Q&T; for welding the order is 42CrMo4 Annealed first (fair, 40/100) then 42CrMo4 Q&T (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 42CrMo4 Annealed and 42CrMo4 Q&T 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.