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Steel Y30-IH vs Y30 QT30-34HRC

Steel · Y30 temper comparison

Y30-IH and Y30 QT30-34HRC are two conditions of the same steel grade, Y30: IH (induction hardened) versus QT30-34HRC. The chemistry is identical, so every difference below comes from the condition. Y30 QT30-34HRC is the stronger of the two: yield strength 830 MPa (120 ksi) against 560 MPa (81.2 ksi) for Y30-IH, about 48% more; tensile strength follows at 1,000 MPa (145 ksi) vs 700 MPa (102 ksi). Y30 QT30-34HRC is the more ductile: elongation 12% versus 10% for Y30-IH, and Y30-IH is harder (560 HB vs 302 HB). Y30 QT30-34HRC runs hotter in service (300°C vs 200°C continuous). On the shop floor, Y30 QT30-34HRC machines more easily (fair vs poor) and Y30 QT30-34HRC welds better (poor vs not recommended).

Y30 QT30-34HRCChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

Y30-IH vs Y30 QT30-34HRC: properties

Y30-IHY30 QT30-34HRC

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

700 MPa102 ksi
1,000 MPa145 ksi

Yield Strength (0.2% offset)

560 MPa81.2 ksi
830 MPa120 ksi

Elongation at Break

10%
12%

Reduction in Area

28%
35%

Compressive Strength

600 MPa87 ksi
540 MPa78.3 ksi

Shear Strength

430 MPa62.4 ksi
600 MPa87 ksi

Fatigue Strength (Endurance Limit)

450 MPa65.3 ksi
430 MPa62.4 ksi

Fracture Toughness (K_IC)

42 MPa·√m38.2 ksi·√in
50 MPa·√m45.5 ksi·√in

Charpy V-Notch Impact (RT)

12 J8.9 ft·lbf
18 J13.3 ft·lbf

Hardness, Brinell

560 HB
302 HB

Hardness, Vickers

580 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 · Hardness, Rockwell B 93 HRB

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.

Thermal Conductivity

44 W/m·K25.4 BTU/hr·ft·°F
47 W/m·K27.2 BTU/hr·ft·°F

Max Service Temperature (continuous)

200°C392 °F
300°C572 °F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.7 µm/m·K6.5 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8.8 % IACS
9.6 % IACS

Electrical Resistivity

1.96×10⁻⁷ Ω·m7.72 µΩ·in
1.8×10⁻⁷ Ω·m7.09 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
48 / 100

Machinability Rating (AISI 1212 = 100 %)

20%
50%

Weldability

8 / 100
25 / 100

Formability (cold)

5 / 100
10 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 50 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 45 L/kg5.4 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 scaleY30

Y30-IH vs Y30 QT30-34HRC — frequently asked

Is Y30 QT30-34HRC stronger than Y30-IH?

Yes. Y30 QT30-34HRC has a typical yield strength of 830 MPa (120 ksi) against 560 MPa (81.2 ksi) for Y30-IH — about 48% more. Tensile strength is 1,000 MPa (145 ksi) vs 700 MPa (102 ksi).

Which condition does FabDigit quote by default, IH or QT30-34HRC?

CD is the default Y30 condition in the FabDigit quote flow (neither IH nor QT30-34HRC). 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, Y30-IH or Y30 QT30-34HRC?

Y30 QT30-34HRC. Its machinability rates fair (48/100) against poor (20/100) for Y30-IH; for welding the order is Y30 QT30-34HRC first (poor, 25/100) then Y30-IH (not recommended, 8/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in Y30-IH and Y30 QT30-34HRC 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.