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Steel G25NiCrMo6 +A vs G25NiCrMo6 +QT1

Steel · G25NiCrMo6 temper comparison

G25NiCrMo6 +A and G25NiCrMo6 +QT1 are two conditions of the same steel grade, G25NiCrMo6: +A (annealed) versus +QT1 (quenched and tempered, lower strength class). The chemistry is identical, so every difference below comes from the condition. G25NiCrMo6 +QT1 is the stronger of the two: yield strength 640 MPa (92.8 ksi) against 400 MPa (58 ksi) for G25NiCrMo6 +A, about 60% more; tensile strength follows at 860 MPa (125 ksi) vs 640 MPa (92.8 ksi). In exchange, G25NiCrMo6 +A is the more ductile: elongation 18% versus 13% for G25NiCrMo6 +QT1, and G25NiCrMo6 +QT1 is harder (255 HB vs 185 HB). G25NiCrMo6 +QT1 runs hotter in service (400°C vs 350°C continuous). On the shop floor, G25NiCrMo6 +A machines more easily (good vs fair) and G25NiCrMo6 +A welds better (50 vs 40 out of 100).

G25NiCrMo6 +AChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

G25NiCrMo6 +QT1Choose it when strength drives the design, or when the part sees heat.

G25NiCrMo6 +A vs G25NiCrMo6 +QT1: properties

G25NiCrMo6 +AG25NiCrMo6 +QT1

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

640 MPa92.8 ksi
860 MPa125 ksi

Yield Strength (0.2% offset)

400 MPa58 ksi
640 MPa92.8 ksi

Elongation at Break

18%
13%

Reduction in Area

45%
35%

Compressive Strength

410 MPa59.5 ksi
650 MPa94.3 ksi

Shear Strength

390 MPa56.6 ksi
520 MPa75.4 ksi

Fatigue Strength (Endurance Limit)

285 MPa41.3 ksi
360 MPa52.2 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
95 MPa·√m86.5 ksi·√in

Hardness, Brinell

185 HB
255 HB

Hardness, Rockwell C

11 HRC
25 HRC

Hardness, Vickers

194 HV
268 HV

Same in both: Elastic (Young's) Modulus 208 GPa30.2 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.29 · Charpy V-Notch Impact (RT) 40 J29.5 ft·lbf

Physical

Density and transition temperatures.

Same in both: Density 7.83 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

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

Thermal Conductivity

41 W/m·K23.7 BTU/hr·ft·°F
38 W/m·K22 BTU/hr·ft·°F

Max Service Temperature (continuous)

350°C662 °F
400°C752 °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 · Min Service Temperature -60°C-76 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7.6 % IACS
7.2 % IACS

Electrical Resistivity

2.27×10⁻⁷ Ω·m8.94 µΩ·in
2.4×10⁻⁷ Ω·m9.45 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.62 V · Corrosion Resistance 16 / 100

Manufacturability

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

Machinability

62 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
50%

Weldability

50 / 100
40 / 100

Formability (cold)

20 / 100
10 / 100

Same in both: Castability 65 / 100 · Brazeability / Solderability 45 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 27 MJ/kg11,608 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 60 L/kg7.2 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 scaleG25NiCrMo6

G25NiCrMo6 +A vs G25NiCrMo6 +QT1 — frequently asked

Is G25NiCrMo6 +QT1 stronger than G25NiCrMo6 +A?

Yes. G25NiCrMo6 +QT1 has a typical yield strength of 640 MPa (92.8 ksi) against 400 MPa (58 ksi) for G25NiCrMo6 +A — about 60% more. Tensile strength is 860 MPa (125 ksi) vs 640 MPa (92.8 ksi).

Which condition does FabDigit quote by default, +A or +QT1?

+QT1 is the default G25NiCrMo6 condition in the FabDigit quote flow. 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, G25NiCrMo6 +A or G25NiCrMo6 +QT1?

G25NiCrMo6 +A. Its machinability rates good (62/100) against fair (45/100) for G25NiCrMo6 +QT1; for welding the order is G25NiCrMo6 +A first (fair, 50/100) then G25NiCrMo6 +QT1 (fair, 40/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in G25NiCrMo6 +A and G25NiCrMo6 +QT1 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.