FabDigitFabDigit

Steel ZG310-570 Q+T vs ZG310-570-SR

Steel · ZG310-570 temper comparison

ZG310-570 Q+T and ZG310-570-SR are two conditions of the same steel grade, ZG310-570: Q+T (quenched and tempered) versus SR (stress relieved). The chemistry is identical, so every difference below comes from the condition. ZG310-570 Q+T is the stronger of the two: yield strength 550 MPa (79.8 ksi) against 315 MPa (45.7 ksi) for ZG310-570-SR, about 75% more; tensile strength follows at 760 MPa (110 ksi) vs 575 MPa (83.4 ksi). In exchange, ZG310-570-SR is the more ductile: elongation 18% versus 14% for ZG310-570 Q+T, and ZG310-570 Q+T is harder (235 HB vs 175 HB). On the shop floor, ZG310-570-SR machines more easily (52 vs 40 out of 100) and ZG310-570-SR welds better (45 vs 35 out of 100).

ZG310-570 Q+TChoose it when strength drives the design.

ZG310-570-SRChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

ZG310-570 Q+T vs ZG310-570-SR: properties

ZG310-570 Q+TZG310-570-SR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

760 MPa110 ksi
575 MPa83.4 ksi

Yield Strength (0.2% offset)

550 MPa79.8 ksi
315 MPa45.7 ksi

Elongation at Break

14%
18%

Reduction in Area

32%
26%

Compressive Strength

340 MPa49.3 ksi
315 MPa45.7 ksi

Shear Strength

530 MPa76.9 ksi
405 MPa58.7 ksi

Fatigue Strength (Endurance Limit)

330 MPa47.9 ksi
245 MPa35.5 ksi

Fracture Toughness (K_IC)

70 MPa·√m63.7 ksi·√in
58 MPa·√m52.8 ksi·√in

Charpy V-Notch Impact (RT)

38 J28 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

235 HB
175 HB

Hardness, Rockwell B

91 HRB
88 HRB

Hardness, Vickers

248 HV
184 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 79 GPa11.5 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.8 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,490°C2,714 °F

Thermal

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

Same in both: Thermal Conductivity 47 W/m·K27.2 BTU/hr·ft·°F · Specific Heat Capacity 480 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 10 % IACS · Electrical Resistivity 1.8×10⁻⁷ Ω·m7.09 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.65 V · Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

40 / 100
52 / 100

Machinability Rating (AISI 1212 = 100 %)

42%
55%

Weldability

35 / 100
45 / 100

Formability (cold)

15 / 100
14 / 100

Same in both: Castability 62 / 100 · Brazeability / Solderability 55 / 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 kg CO₂/kg · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 85%

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 scaleZG310-570

ZG310-570 Q+T vs ZG310-570-SR — frequently asked

Is ZG310-570 Q+T stronger than ZG310-570-SR?

Yes. ZG310-570 Q+T has a typical yield strength of 550 MPa (79.8 ksi) against 315 MPa (45.7 ksi) for ZG310-570-SR — about 75% more. Tensile strength is 760 MPa (110 ksi) vs 575 MPa (83.4 ksi).

Which condition does FabDigit quote by default, Q+T or SR?

N+T is the default ZG310-570 condition in the FabDigit quote flow (neither Q+T nor SR). 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, ZG310-570 Q+T or ZG310-570-SR?

ZG310-570-SR, by a small margin. Both rate fair for machinability — 52/100 against 40/100 for ZG310-570 Q+T; for welding the order is ZG310-570-SR first (fair, 45/100) then ZG310-570 Q+T (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in ZG310-570 Q+T and ZG310-570-SR 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.