FabDigitFabDigit

Steel 4028-IH vs 4028-QT205

Steel · 4028 temper comparison

4028-IH and 4028-QT205 are two conditions of the same steel grade, 4028: IH (induction hardened) versus QT205. The chemistry is identical, so every difference below comes from the condition. 4028-QT205 is the stronger of the two: yield strength 745 MPa (108 ksi) against 450 MPa (65.3 ksi) for 4028-IH, about 66% more; tensile strength follows at 1,000 MPa (145 ksi) vs 620 MPa (89.9 ksi). 4028-QT205 is the more ductile: elongation 12% versus 10% for 4028-IH, and 4028-IH is harder (460 HB vs 302 HB). 4028-IH runs hotter in service (200°C vs 175°C continuous). On the shop floor, 4028-QT205 machines more easily (fair vs poor) and 4028-QT205 welds better (30 vs 15 out of 100).

4028-IHChoose it when the part sees heat.

4028-QT205Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

4028-IH vs 4028-QT205: properties

4028-IH4028-QT205

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

620 MPa89.9 ksi
1,000 MPa145 ksi

Yield Strength (0.2% offset)

450 MPa65.3 ksi
745 MPa108 ksi

Elongation at Break

10%
12%

Reduction in Area

30%
40%

Compressive Strength

520 MPa75.4 ksi
505 MPa73.2 ksi

Shear Strength

380 MPa55.1 ksi
350 MPa50.8 ksi

Fatigue Strength (Endurance Limit)

400 MPa58 ksi
420 MPa60.9 ksi

Hardness, Brinell

460 HB
302 HB

Hardness, Vickers

490 HV
318 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Charpy V-Notch Impact (RT) 20 J14.8 ft·lbf · Hardness, Rockwell B 89 HRB

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.

Thermal Conductivity

42 W/m·K24.3 BTU/hr·ft·°F
44 W/m·K25.4 BTU/hr·ft·°F

Max Service Temperature (continuous)

200°C392 °F
175°C347 °F

Same in both: Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.2 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7.5 % IACS
8 % IACS

Electrical Resistivity

2.3×10⁻⁷ Ω·m9.06 µΩ·in
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) -0.62 V · Corrosion Resistance 11 / 100

Manufacturability

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

Machinability

20 / 100
42 / 100

Machinability Rating (AISI 1212 = 100 %)

20%
45%

Weldability

15 / 100
30 / 100

Formability (cold)

5 / 100
10 / 100

Same in both: Castability 40 / 100 · Brazeability / Solderability 60 / 100 · Polishability 45 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 35%

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 scale4028

4028-IH vs 4028-QT205 — frequently asked

Is 4028-QT205 stronger than 4028-IH?

Yes. 4028-QT205 has a typical yield strength of 745 MPa (108 ksi) against 450 MPa (65.3 ksi) for 4028-IH — about 66% more. Tensile strength is 1,000 MPa (145 ksi) vs 620 MPa (89.9 ksi).

Which condition does FabDigit quote by default, IH or QT205?

CD is the default 4028 condition in the FabDigit quote flow (neither IH nor QT205). 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, 4028-IH or 4028-QT205?

4028-QT205. Its machinability rates fair (42/100) against poor (20/100) for 4028-IH; for welding the order is 4028-QT205 first (poor, 30/100) then 4028-IH (poor, 15/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4028-IH and 4028-QT205 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.