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Steel GCr15SiMn-CD vs GCr15SiMn-QT61

Steel · GCr15SiMn temper comparison

GCr15SiMn-CD and GCr15SiMn-QT61 are two conditions of the same steel grade, GCr15SiMn: CD (cold drawn) versus QT61 (Q&T 61-64 HRC). The chemistry is identical, so every difference below comes from the condition. GCr15SiMn-QT61 is the stronger of the two: yield strength 1,900 MPa (276 ksi) against 700 MPa (102 ksi) for GCr15SiMn-CD, about 171% more; tensile strength follows at 2,300 MPa (334 ksi) vs 880 MPa (128 ksi). In exchange, GCr15SiMn-CD is the more ductile: elongation 10% versus 1% for GCr15SiMn-QT61, and GCr15SiMn-CD is harder (240 HB vs 195 HB). GCr15SiMn-CD runs hotter in service (250°C vs 120°C continuous) and GCr15SiMn-CD conducts heat better (44 W/m·K vs 36 W/m·K). On the shop floor, GCr15SiMn-CD machines more easily (fair vs not recommended).

GCr15SiMn-CDChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

GCr15SiMn-QT61Choose it when strength drives the design.

GCr15SiMn-CD vs GCr15SiMn-QT61: properties

GCr15SiMn-CDGCr15SiMn-QT61

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

208 GPa30.2 Msi
210 GPa30.5 Msi

Tensile Strength (Ultimate)

880 MPa128 ksi
2,300 MPa334 ksi

Yield Strength (0.2% offset)

700 MPa102 ksi
1,900 MPa276 ksi

Elongation at Break

10%
1%

Reduction in Area

35%
45%

Compressive Strength

950 MPa138 ksi
3,200 MPa464 ksi

Shear Strength

530 MPa76.9 ksi
1,350 MPa196 ksi

Fatigue Strength (Endurance Limit)

400 MPa58 ksi
780 MPa113 ksi

Fracture Toughness (K_IC)

45 MPa·√m41 ksi·√in
17 MPa·√m15.5 ksi·√in

Charpy V-Notch Impact (RT)

14 J10.3 ft·lbf
5 J3.7 ft·lbf

Hardness, Brinell

240 HB
195 HB

Hardness, Rockwell B

100 HRB
92 HRB

Hardness, Vickers

252 HV
780 HV

Same in both: Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Same in both: Density 7.81 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,470°C2,678 °F

Thermal

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

Thermal Conductivity

44 W/m·K25.4 BTU/hr·ft·°F
36 W/m·K20.8 BTU/hr·ft·°F

Max Service Temperature (continuous)

250°C482 °F
120°C248 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.5 % IACS · Electrical Resistivity 2.3×10⁻⁷ Ω·m9.06 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

46 / 100
8 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
5%

Weldability

10 / 100
5 / 100

Formability (cold)

20 / 100
2 / 100

Polishability

88 / 100
92 / 100

Same in both: Brazeability / Solderability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 32 MJ/kg13,758 BTU/lb · Embodied Carbon (primary production) 2.3 kg CO₂/kg · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 25%

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 scaleGCr15SiMn

GCr15SiMn-CD vs GCr15SiMn-QT61 — frequently asked

Is GCr15SiMn-QT61 stronger than GCr15SiMn-CD?

Yes. GCr15SiMn-QT61 has a typical yield strength of 1,900 MPa (276 ksi) against 700 MPa (102 ksi) for GCr15SiMn-CD — about 171% more. Tensile strength is 2,300 MPa (334 ksi) vs 880 MPa (128 ksi).

Which condition does FabDigit quote by default, CD or QT61?

A is the default GCr15SiMn condition in the FabDigit quote flow (neither CD nor QT61). 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, GCr15SiMn-CD or GCr15SiMn-QT61?

GCr15SiMn-CD. Its machinability rates fair (46/100) against not recommended (8/100) for GCr15SiMn-QT61; for welding the order is GCr15SiMn-CD first (not recommended, 10/100) then GCr15SiMn-QT61 (not recommended, 5/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in GCr15SiMn-CD and GCr15SiMn-QT61 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.