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Steel 35CD4-HR vs 35CD4 +QT

Steel · 35CD4 temper comparison

35CD4-HR and 35CD4 +QT are two conditions of the same steel grade, 35CD4: HR (hot rolled) versus +QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 35CD4 +QT is the stronger of the two: yield strength 700 MPa (102 ksi) against 440 MPa (63.8 ksi) for 35CD4-HR, about 59% more; tensile strength follows at 950 MPa (138 ksi) vs 700 MPa (102 ksi). In exchange, 35CD4-HR is the more ductile: elongation 18% versus 14% for 35CD4 +QT, and 35CD4 +QT is harder (285 HB vs 215 HB).

35CD4-HRChoose it when the part is bent, formed or impact-loaded.

35CD4 +QTChoose it when strength drives the design.

35CD4-HR vs 35CD4 +QT: properties

35CD4-HR35CD4 +QT

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

700 MPa102 ksi
950 MPa138 ksi

Yield Strength (0.2% offset)

440 MPa63.8 ksi
700 MPa102 ksi

Elongation at Break

18%
14%

Compressive Strength

440 MPa63.8 ksi
700 MPa102 ksi

Shear Strength

420 MPa60.9 ksi
570 MPa82.7 ksi

Fatigue Strength (Endurance Limit)

340 MPa49.3 ksi
450 MPa65.3 ksi

Fracture Toughness (K_IC)

95 MPa·√m86.5 ksi·√in
85 MPa·√m77.4 ksi·√in

Charpy V-Notch Impact (RT)

50 J36.9 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

215 HB
285 HB

Hardness, Rockwell C

17 HRC
29 HRC

Hardness, Vickers

226 HV
300 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Reduction in Area 50%

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 1,490°C2,714 °F

Thermal

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

Thermal Conductivity

43 W/m·K24.8 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 450°C842 °F · 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).

Corrosion Resistance

10 / 100
12 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V

Manufacturability

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

Machinability

56 / 100
52 / 100

Machinability Rating (AISI 1212 = 100 %)

58%
55%

Weldability

48 / 100
45 / 100

Formability (cold)

40 / 100
30 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 65 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 33 MJ/kg14,187 BTU/lb · Embodied Carbon (primary production) 2.3 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 scale35CD4

35CD4-HR vs 35CD4 +QT — frequently asked

Is 35CD4 +QT stronger than 35CD4-HR?

Yes. 35CD4 +QT has a typical yield strength of 700 MPa (102 ksi) against 440 MPa (63.8 ksi) for 35CD4-HR — about 59% more. Tensile strength is 950 MPa (138 ksi) vs 700 MPa (102 ksi).

Which condition does FabDigit quote by default, HR or +QT?

+QT is the default 35CD4 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 35CD4-HR over 35CD4 +QT?

Pick 35CD4-HR when the part is bent, formed or impact-loaded. Pick 35CD4 +QT when strength drives the design.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 35CD4-HR and 35CD4 +QT 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.