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Steel G42CrMo4 +N vs G42CrMo4 +QT2

Steel · G42CrMo4 temper comparison

G42CrMo4 +N and G42CrMo4 +QT2 are two conditions of the same steel grade, G42CrMo4: +N (normalized) versus +QT2 (quenched and tempered, higher strength class). The chemistry is identical, so every difference below comes from the condition. G42CrMo4 +QT2 is the stronger of the two: yield strength 740 MPa (107 ksi) against 450 MPa (65.3 ksi) for G42CrMo4 +N, about 64% more; tensile strength follows at 920 MPa (133 ksi) vs 700 MPa (102 ksi). In exchange, G42CrMo4 +N is the more ductile: elongation 16% versus 11% for G42CrMo4 +QT2, and G42CrMo4 +QT2 is harder (280 HB vs 215 HB). On the shop floor, G42CrMo4 +N machines more easily (54 vs 42 out of 100) and G42CrMo4 +N welds better (fair vs poor).

G42CrMo4 +NChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

G42CrMo4 +QT2Choose it when strength drives the design.

G42CrMo4 +N vs G42CrMo4 +QT2: properties

G42CrMo4 +NG42CrMo4 +QT2

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

700 MPa102 ksi
920 MPa133 ksi

Yield Strength (0.2% offset)

450 MPa65.3 ksi
740 MPa107 ksi

Elongation at Break

16%
11%

Reduction in Area

45%
32%

Compressive Strength

450 MPa65.3 ksi
740 MPa107 ksi

Shear Strength

430 MPa62.4 ksi
565 MPa81.9 ksi

Fatigue Strength (Endurance Limit)

285 MPa41.3 ksi
360 MPa52.2 ksi

Fracture Toughness (K_IC)

75 MPa·√m68.3 ksi·√in
70 MPa·√m63.7 ksi·√in

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
28 J20.7 ft·lbf

Hardness, Brinell

215 HB
280 HB

Hardness, Rockwell C

18 HRC
29 HRC

Hardness, Vickers

225 HV
295 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.

Thermal Conductivity

43 W/m·K24.8 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 470 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 270 J/g116 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -30°C-22 °F

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 15 / 100

Manufacturability

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

Machinability

54 / 100
42 / 100

Machinability Rating (AISI 1212 = 100 %)

58%
45%

Weldability

40 / 100
28 / 100

Formability (cold)

14 / 100
10 / 100

Same in both: Castability 60 / 100 · Brazeability / Solderability 50 / 100 · Polishability 60 / 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 55 L/kg6.6 gal/lb · Typical Recycled Content 80%

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 scaleG42CrMo4

G42CrMo4 +N vs G42CrMo4 +QT2 — frequently asked

Is G42CrMo4 +QT2 stronger than G42CrMo4 +N?

Yes. G42CrMo4 +QT2 has a typical yield strength of 740 MPa (107 ksi) against 450 MPa (65.3 ksi) for G42CrMo4 +N — about 64% more. Tensile strength is 920 MPa (133 ksi) vs 700 MPa (102 ksi).

Which condition does FabDigit quote by default, +N or +QT2?

+QT1 is the default G42CrMo4 condition in the FabDigit quote flow (neither +N nor +QT2). 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, G42CrMo4 +N or G42CrMo4 +QT2?

G42CrMo4 +N, by a small margin. Both rate fair for machinability — 54/100 against 42/100 for G42CrMo4 +QT2; for welding the order is G42CrMo4 +N first (fair, 40/100) then G42CrMo4 +QT2 (poor, 28/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in G42CrMo4 +N and G42CrMo4 +QT2 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.