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Stainless Steel 7Cr17-HR vs 7Cr17-QT45

Stainless Steel · 7Cr17 temper comparison

7Cr17-HR and 7Cr17-QT45 are two conditions of the same stainless steel grade, 7Cr17: HR (hot rolled) versus QT45 (Q&T ~44–48 HRC). The chemistry is identical, so every difference below comes from the condition. 7Cr17-QT45 is the stronger of the two: yield strength 1,250 MPa (181 ksi) against 430 MPa (62.4 ksi) for 7Cr17-HR, about 191% more; tensile strength follows at 1,450 MPa (210 ksi) vs 760 MPa (110 ksi). In exchange, 7Cr17-HR is the more ductile: elongation 18% versus 8% for 7Cr17-QT45, and 7Cr17-QT45 is harder (460 HV vs 240 HV). 7Cr17-HR runs hotter in service (425°C vs 250°C continuous). On the shop floor, 7Cr17-HR machines more easily (fair vs poor).

7Cr17-HRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

7Cr17-QT45Choose it when strength drives the design.

7Cr17-HR vs 7Cr17-QT45: properties

7Cr17-HR7Cr17-QT45

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

760 MPa110 ksi
1,450 MPa210 ksi

Yield Strength (0.2% offset)

430 MPa62.4 ksi
1,250 MPa181 ksi

Elongation at Break

18%
8%

Reduction in Area

42%
45%

Compressive Strength

445 MPa64.5 ksi
430 MPa62.4 ksi

Shear Strength

480 MPa69.6 ksi
470 MPa68.2 ksi

Fatigue Strength (Endurance Limit)

350 MPa50.8 ksi
620 MPa89.9 ksi

Fracture Toughness (K_IC)

58 MPa·√m52.8 ksi·√in
28 MPa·√m25.5 ksi·√in

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
14 J10.3 ft·lbf

Hardness, Brinell

230 HB
220 HB

Hardness, Rockwell B

97 HRB
96 HRB

Hardness, Vickers

240 HV
460 HV

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 78 GPa11.3 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.28

Physical

Density and transition temperatures.

Same in both: Density 7.7 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,370°C2,498 °F · Liquidus Temperature 1,425°C2,597 °F

Thermal

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

Max Service Temperature (continuous)

425°C797 °F
250°C482 °F

Same in both: Thermal Conductivity 24 W/m·K13.9 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.2 µm/m·K5.7 µin/in·°F · Latent Heat of Fusion 260 J/g112 BTU/lb · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 2.9 % IACS · Electrical Resistivity 6×10⁻⁷ Ω·m23.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

45 / 100
48 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.3 V

Manufacturability

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

Machinability

42 / 100
15 / 100

Weldability

22 / 100
20 / 100

Formability (cold)

28 / 100
30 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 45% · Castability 35 / 100 · Brazeability / Solderability 45 / 100 · Polishability 75 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 45 MJ/kg19,347 BTU/lb · Embodied Carbon (primary production) 3.5 kg CO₂/kg · Embodied Water 130 L/kg15.6 gal/lb · Typical Recycled Content 50%

Strength versus weight

Yield strength against density for every stainless steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

3005007001,0001,5002,0007.27.47.67.888.2Density (g/cm³)Yield strength (MPa) — log scale7Cr17

7Cr17-HR vs 7Cr17-QT45 — frequently asked

Is 7Cr17-QT45 stronger than 7Cr17-HR?

Yes. 7Cr17-QT45 has a typical yield strength of 1,250 MPa (181 ksi) against 430 MPa (62.4 ksi) for 7Cr17-HR — about 191% more. Tensile strength is 1,450 MPa (210 ksi) vs 760 MPa (110 ksi).

Which condition does FabDigit quote by default, HR or QT45?

A is the default 7Cr17 condition in the FabDigit quote flow (neither HR nor QT45). 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, 7Cr17-HR or 7Cr17-QT45?

7Cr17-HR. Its machinability rates fair (42/100) against poor (15/100) for 7Cr17-QT45.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 7Cr17-HR and 7Cr17-QT45 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.