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Steel 4335V (Modified 4340)-QT200 vs 4335V (Modified 4340)-QT220

Steel · 4335V (Modified 4340) temper comparison

4335V (Modified 4340)-QT200 and 4335V (Modified 4340)-QT220 are two conditions of the same steel grade, 4335V (Modified 4340): QT200 (Q&T 1380 MPa) versus QT220 (Q&T 1520 MPa). The chemistry is identical, so every difference below comes from the condition. 4335V (Modified 4340)-QT220 is the stronger of the two: yield strength 1,380 MPa (200 ksi) against 1,240 MPa (180 ksi) for 4335V (Modified 4340)-QT200, about 11% more; tensile strength follows at 1,520 MPa (220 ksi) vs 1,380 MPa (200 ksi). 4335V (Modified 4340)-QT220 is harder — 440 HB against 401 HB for 4335V (Modified 4340)-QT200 — which matters for wear surfaces and threads. 4335V (Modified 4340)-QT200 runs hotter in service (340°C vs 300°C continuous).

4335V (Modified 4340)-QT200Choose it when the part sees heat.

4335V (Modified 4340)-QT220Choose it when strength drives the design, or when surface hardness matters.

4335V (Modified 4340)-QT200 vs 4335V (Modified 4340)-QT220: properties

4335V (Modified 4340)-QT2004335V (Modified 4340)-QT220

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

1,380 MPa200 ksi
1,520 MPa220 ksi

Yield Strength (0.2% offset)

1,240 MPa180 ksi
1,380 MPa200 ksi

Elongation at Break

13%
12%

Reduction in Area

47%
43%

Compressive Strength

1,300 MPa189 ksi
1,440 MPa209 ksi

Shear Strength

840 MPa122 ksi
915 MPa133 ksi

Fatigue Strength (Endurance Limit)

660 MPa95.7 ksi
700 MPa102 ksi

Fracture Toughness (K_IC)

88 MPa·√m80.1 ksi·√in
75 MPa·√m68.3 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

401 HB
440 HB

Hardness, Rockwell C

43 HRC
46 HRC

Hardness, Vickers

425 HV
465 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 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.83 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,416°C2,581 °F · Liquidus Temperature 1,490°C2,714 °F

Thermal

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

Max Service Temperature (continuous)

340°C644 °F
300°C572 °F

Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Specific Heat Capacity 475 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 · Min Service Temperature -73°C-99 °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

27 / 100
22 / 100

Machinability Rating (AISI 1212 = 100 %)

27%
22%

Same in both: Weldability 22 / 100 · Formability (cold) 10 / 100 · Brazeability / Solderability 35 / 100 · Polishability 78 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.6 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 scale4335V (Modified 4340)

4335V (Modified 4340)-QT200 vs 4335V (Modified 4340)-QT220 — frequently asked

Is 4335V (Modified 4340)-QT220 stronger than 4335V (Modified 4340)-QT200?

Yes. 4335V (Modified 4340)-QT220 has a typical yield strength of 1,380 MPa (200 ksi) against 1,240 MPa (180 ksi) for 4335V (Modified 4340)-QT200 — about 11% more. Tensile strength is 1,520 MPa (220 ksi) vs 1,380 MPa (200 ksi).

Which condition does FabDigit quote by default, QT200 or QT220?

QT220 is the default 4335V (Modified 4340) 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.

Which is easier to machine, 4335V (Modified 4340)-QT200 or 4335V (Modified 4340)-QT220?

4335V (Modified 4340)-QT200, by a small margin. Both rate poor for machinability — 27/100 against 22/100 for 4335V (Modified 4340)-QT220.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4335V (Modified 4340)-QT200 and 4335V (Modified 4340)-QT220 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.