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Steel P420QH-QT vs P420QH QT-100-160

Steel · P420QH temper comparison

P420QH-QT and P420QH QT-100-160 are two conditions of the same steel grade, P420QH: QT (quenched and tempered) versus QT-100-160 (QT). The chemistry is identical, so every difference below comes from the condition. P420QH-QT is the stronger of the two: yield strength 470 MPa (68.2 ksi) against 415 MPa (60.2 ksi) for P420QH QT-100-160, about 13% more; tensile strength follows at 590 MPa (85.6 ksi) vs 550 MPa (79.8 ksi). P420QH-QT is harder — 195 HB against 180 HB for P420QH QT-100-160 — which matters for wear surfaces and threads.

P420QH-QTChoose it when strength drives the design, or when surface hardness matters.

P420QH-QT vs P420QH QT-100-160: properties

P420QH-QTP420QH QT-100-160

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

590 MPa85.6 ksi
550 MPa79.8 ksi

Yield Strength (0.2% offset)

470 MPa68.2 ksi
415 MPa60.2 ksi

Elongation at Break

22%
21%

Reduction in Area

60%
55%

Compressive Strength

470 MPa68.2 ksi
415 MPa60.2 ksi

Shear Strength

360 MPa52.2 ksi
330 MPa47.9 ksi

Fatigue Strength (Endurance Limit)

280 MPa40.6 ksi
260 MPa37.7 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

195 HB
180 HB

Hardness, Rockwell B

92 HRB
88 HRB

Hardness, Rockwell C

12 HRC
9 HRC

Hardness, Vickers

205 HV
190 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 0.3

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °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 39 W/m·K22.5 BTU/hr·ft·°F · Specific Heat Capacity 460 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) 400°C752 °F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.2 % 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) -0.62 V · Corrosion Resistance 13 / 100

Manufacturability

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

Machinability

48 / 100
52 / 100

Machinability Rating (AISI 1212 = 100 %)

58%
62%

Weldability

68 / 100
64 / 100

Formability (cold)

45 / 100
42 / 100

Same in both: Brazeability / Solderability 45 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 29 MJ/kg12,468 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 45 L/kg5.4 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 scaleP420QH

P420QH-QT vs P420QH QT-100-160 — frequently asked

Is P420QH-QT stronger than P420QH QT-100-160?

Yes. P420QH-QT has a typical yield strength of 470 MPa (68.2 ksi) against 415 MPa (60.2 ksi) for P420QH QT-100-160 — about 13% more. Tensile strength is 590 MPa (85.6 ksi) vs 550 MPa (79.8 ksi).

Which condition does FabDigit quote by default, QT or QT-100-160?

QT is the default P420QH condition in the FabDigit quote flow. 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.

When should I choose P420QH-QT over P420QH QT-100-160?

Pick P420QH-QT when strength drives the design, or when surface hardness matters.

Ready to make it?

Upload a CAD file and FabDigit prices the part in P420QH-QT and P420QH QT-100-160 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.