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Steel XAR 400 QT-400HB-THICK vs XAR 400 QT-400HB-THIN

Steel · XAR 400 temper comparison

XAR 400 QT-400HB-THICK and XAR 400 QT-400HB-THIN are two conditions of the same steel grade, XAR 400: QT-400HB-THICK (Q&T 400 HB heavy gauge) versus QT-400HB-THIN (Q&T 400 HB thin gauge). The chemistry is identical, so every difference below comes from the condition. XAR 400 QT-400HB-THIN is the stronger of the two: yield strength 1,050 MPa (152 ksi) against 950 MPa (138 ksi) for XAR 400 QT-400HB-THICK, about 11% more; tensile strength follows at 1,300 MPa (189 ksi) vs 1,180 MPa (171 ksi). XAR 400 QT-400HB-THIN is harder — 405 HB against 380 HB for XAR 400 QT-400HB-THICK — which matters for wear surfaces and threads. On the shop floor, XAR 400 QT-400HB-THIN welds better (good vs fair) and XAR 400 QT-400HB-THIN forms better (fair vs poor).

XAR 400 QT-400HB-THINChoose it when strength drives the design, or when surface hardness matters.

XAR 400 QT-400HB-THICK vs XAR 400 QT-400HB-THIN: properties

XAR 400 QT-400HB-THICKXAR 400 QT-400HB-THIN

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

1,180 MPa171 ksi
1,300 MPa189 ksi

Yield Strength (0.2% offset)

950 MPa138 ksi
1,050 MPa152 ksi

Elongation at Break

10%
11%

Reduction in Area

38%
42%

Compressive Strength

950 MPa138 ksi
1,050 MPa152 ksi

Shear Strength

710 MPa103 ksi
780 MPa113 ksi

Fatigue Strength (Endurance Limit)

520 MPa75.4 ksi
580 MPa84.1 ksi

Fracture Toughness (K_IC)

75 MPa·√m68.3 ksi·√in
85 MPa·√m77.4 ksi·√in

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

380 HB
405 HB

Hardness, Rockwell C

41 HRC
43 HRC

Hardness, Vickers

400 HV
425 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

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

Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · 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 270 J/g116 BTU/lb · Max Service Temperature (continuous) 250°C482 °F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7 % IACS · Electrical Resistivity 2.4×10⁻⁷ Ω·m9.45 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

28 / 100
24 / 100

Machinability Rating (AISI 1212 = 100 %)

28%
24%

Weldability

50 / 100
68 / 100

Formability (cold)

25 / 100
50 / 100

Same in both: Brazeability / Solderability 25 / 100 · Polishability 45 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 31 MJ/kg13,328 BTU/lb · Embodied Carbon (primary production) 2.3 kg CO₂/kg · Embodied Water 60 L/kg7.2 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 scaleXAR 400

XAR 400 QT-400HB-THICK vs XAR 400 QT-400HB-THIN — frequently asked

Is XAR 400 QT-400HB-THIN stronger than XAR 400 QT-400HB-THICK?

Yes. XAR 400 QT-400HB-THIN has a typical yield strength of 1,050 MPa (152 ksi) against 950 MPa (138 ksi) for XAR 400 QT-400HB-THICK — about 11% more. Tensile strength is 1,300 MPa (189 ksi) vs 1,180 MPa (171 ksi).

Which condition does FabDigit quote by default, QT-400HB-THICK or QT-400HB-THIN?

QT-400HB is the default XAR 400 condition in the FabDigit quote flow (neither QT-400HB-THICK nor QT-400HB-THIN). 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 welds better, XAR 400 QT-400HB-THICK or XAR 400 QT-400HB-THIN?

XAR 400 QT-400HB-THIN. Its weldability rates good (68/100) against fair (50/100) for XAR 400 QT-400HB-THICK.

Ready to make it?

Upload a CAD file and FabDigit prices the part in XAR 400 QT-400HB-THICK and XAR 400 QT-400HB-THIN 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.