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Steel SUJ3-HR vs SUJ3-QT160

Steel · SUJ3 temper comparison

SUJ3-HR and SUJ3-QT160 are two conditions of the same steel grade, SUJ3: HR (hot rolled) versus QT160 (oil hardened, tempered 150–170 °C). The chemistry is identical, so every difference below comes from the condition. SUJ3-QT160 is the stronger of the two: yield strength 1,800 MPa (261 ksi) against 600 MPa (87 ksi) for SUJ3-HR, about 3.0 times as much; tensile strength follows at 2,200 MPa (319 ksi) vs 980 MPa (142 ksi). In exchange, SUJ3-HR is the more ductile: elongation 10% versus 1% for SUJ3-QT160, and SUJ3-HR is harder (290 HB vs 195 HB). SUJ3-HR runs hotter in service (200°C vs 120°C continuous) and SUJ3-HR conducts heat better (42 W/m·K vs 34 W/m·K). On the shop floor, SUJ3-HR machines more easily (poor vs not recommended).

SUJ3-HRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

SUJ3-QT160Choose it when strength drives the design.

SUJ3-HR vs SUJ3-QT160: properties

SUJ3-HRSUJ3-QT160

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

208 GPa30.2 Msi
210 GPa30.5 Msi

Tensile Strength (Ultimate)

980 MPa142 ksi
2,200 MPa319 ksi

Yield Strength (0.2% offset)

600 MPa87 ksi
1,800 MPa261 ksi

Elongation at Break

10%
1%

Reduction in Area

25%
45%

Compressive Strength

1,020 MPa148 ksi
3,300 MPa479 ksi

Shear Strength

590 MPa85.6 ksi
1,500 MPa218 ksi

Fatigue Strength (Endurance Limit)

430 MPa62.4 ksi
850 MPa123 ksi

Charpy V-Notch Impact (RT)

8 J5.9 ft·lbf
5 J3.7 ft·lbf

Hardness, Brinell

290 HB
195 HB

Hardness, Vickers

305 HV
790 HV

Same in both: Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Rockwell B 92 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.81 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,450°C2,642 °F

Thermal

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

Thermal Conductivity

42 W/m·K24.3 BTU/hr·ft·°F
34 W/m·K19.6 BTU/hr·ft·°F

Max Service Temperature (continuous)

200°C392 °F
120°C248 °F

Same in both: Specific Heat Capacity 470 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 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 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

25 / 100
5 / 100

Machinability Rating (AISI 1212 = 100 %)

22%
40%

Weldability

5 / 100
3 / 100

Formability (cold)

12 / 100
2 / 100

Polishability

85 / 100
92 / 100

Same in both: Brazeability / Solderability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 31 MJ/kg13,328 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 30%

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 scaleSUJ3

SUJ3-HR vs SUJ3-QT160 — frequently asked

Is SUJ3-QT160 stronger than SUJ3-HR?

Yes. SUJ3-QT160 has a typical yield strength of 1,800 MPa (261 ksi) against 600 MPa (87 ksi) for SUJ3-HR — about 3.0 times as much. Tensile strength is 2,200 MPa (319 ksi) vs 980 MPa (142 ksi).

Which condition does FabDigit quote by default, HR or QT160?

A is the default SUJ3 condition in the FabDigit quote flow (neither HR nor QT160). 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, SUJ3-HR or SUJ3-QT160?

SUJ3-HR. Its machinability rates poor (25/100) against not recommended (5/100) for SUJ3-QT160.

Ready to make it?

Upload a CAD file and FabDigit prices the part in SUJ3-HR and SUJ3-QT160 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.