FabDigitFabDigit

Stainless Steel 9Cr18MoV-QT45 vs 9Cr18MoV-QT52

Stainless Steel · 9Cr18MoV temper comparison

9Cr18MoV-QT45 and 9Cr18MoV-QT52 are two conditions of the same stainless steel grade, 9Cr18MoV: QT45 (Q&T 45–50 HRC) versus QT52 (Q&T 50–55 HRC). The chemistry is identical, so every difference below comes from the condition. 9Cr18MoV-QT52 is the stronger of the two: yield strength 1,500 MPa (218 ksi) against 1,250 MPa (181 ksi) for 9Cr18MoV-QT45, about 20% more; tensile strength follows at 1,750 MPa (254 ksi) vs 1,500 MPa (218 ksi). In exchange, 9Cr18MoV-QT45 is the more ductile: elongation 6% versus 4% for 9Cr18MoV-QT52, and 9Cr18MoV-QT52 is harder (570 HV vs 480 HV). 9Cr18MoV-QT45 runs hotter in service (350°C vs 250°C continuous).

9Cr18MoV-QT45Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

9Cr18MoV-QT52Choose it when strength drives the design.

9Cr18MoV-QT45 vs 9Cr18MoV-QT52: properties

9Cr18MoV-QT459Cr18MoV-QT52

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

1,500 MPa218 ksi
1,750 MPa254 ksi

Yield Strength (0.2% offset)

1,250 MPa181 ksi
1,500 MPa218 ksi

Elongation at Break

6%
4%

Reduction in Area

15%
10%

Compressive Strength

1,600 MPa232 ksi
1,900 MPa276 ksi

Shear Strength

900 MPa131 ksi
1,050 MPa152 ksi

Fatigue Strength (Endurance Limit)

620 MPa89.9 ksi
700 MPa102 ksi

Fracture Toughness (K_IC)

26 MPa·√m23.7 ksi·√in
23 MPa·√m20.9 ksi·√in

Charpy V-Notch Impact (RT)

12 J8.9 ft·lbf
9 J6.6 ft·lbf

Hardness, Vickers

480 HV
570 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 · Hardness, Brinell 225 HB · Hardness, Rockwell B 98 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.7 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,480°C2,696 °F

Thermal

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

Max Service Temperature (continuous)

350°C662 °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 270 J/g116 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

35 / 100
42 / 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

15 / 100
10 / 100

Polishability

80 / 100
85 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 40% · Weldability 12 / 100 · Formability (cold) 30 / 100 · Brazeability / Solderability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 53 MJ/kg22,786 BTU/lb · Embodied Carbon (primary production) 4.8 kg CO₂/kg · Embodied Water 120 L/kg14.4 gal/lb · Typical Recycled Content 40%

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 scale9Cr18MoV

9Cr18MoV-QT45 vs 9Cr18MoV-QT52 — frequently asked

Is 9Cr18MoV-QT52 stronger than 9Cr18MoV-QT45?

Yes. 9Cr18MoV-QT52 has a typical yield strength of 1,500 MPa (218 ksi) against 1,250 MPa (181 ksi) for 9Cr18MoV-QT45 — about 20% more. Tensile strength is 1,750 MPa (254 ksi) vs 1,500 MPa (218 ksi).

Which condition does FabDigit quote by default, QT45 or QT52?

A is the default 9Cr18MoV condition in the FabDigit quote flow (neither QT45 nor QT52). 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, 9Cr18MoV-QT45 or 9Cr18MoV-QT52?

9Cr18MoV-QT45. Its machinability rates poor (15/100) against not recommended (10/100) for 9Cr18MoV-QT52.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 9Cr18MoV-QT45 and 9Cr18MoV-QT52 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.