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Steel 4027-N vs 4027-QT315

Steel · 4027 temper comparison

4027-N and 4027-QT315 are two conditions of the same steel grade, 4027: N (normalized) versus QT315 (Q&T 315 °C). The chemistry is identical, so every difference below comes from the condition. 4027-QT315 is the stronger of the two: yield strength 760 MPa (110 ksi) against 415 MPa (60.2 ksi) for 4027-N, about 83% more; tensile strength follows at 950 MPa (138 ksi) vs 655 MPa (95 ksi). In exchange, 4027-N is the more ductile: elongation 26% versus 15% for 4027-QT315, and 4027-QT315 is harder (285 HB vs 179 HB). 4027-N runs hotter in service (400°C vs 250°C continuous). On the shop floor, 4027-N machines more easily (good vs fair) and 4027-N welds better (good vs fair).

4027-NChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

4027-QT315Choose it when strength drives the design.

4027-N vs 4027-QT315: properties

4027-N4027-QT315

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

655 MPa95 ksi
950 MPa138 ksi

Yield Strength (0.2% offset)

415 MPa60.2 ksi
760 MPa110 ksi

Elongation at Break

26%
15%

Reduction in Area

60%
51%

Compressive Strength

415 MPa60.2 ksi
790 MPa115 ksi

Shear Strength

435 MPa63.1 ksi
620 MPa89.9 ksi

Fatigue Strength (Endurance Limit)

320 MPa46.4 ksi
440 MPa63.8 ksi

Fracture Toughness (K_IC)

95 MPa·√m86.5 ksi·√in
62 MPa·√m56.4 ksi·√in

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
35 J25.8 ft·lbf

Hardness, Brinell

179 HB
285 HB

Hardness, Rockwell B

88 HRB
78 HRB

Hardness, Vickers

188 HV
300 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

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
43 W/m·K24.8 BTU/hr·ft·°F

Max Service Temperature (continuous)

400°C752 °F
250°C482 °F

Same in both: Specific Heat Capacity 470 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
7.3 % IACS

Electrical Resistivity

2.3×10⁻⁷ Ω·m9.06 µΩ·in
2.35×10⁻⁷ Ω·m9.25 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

58 / 100
42 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
45%

Weldability

60 / 100
42 / 100

Formability (cold)

46 / 100
18 / 100

Same in both: Castability 40 / 100 · Brazeability / Solderability 70 / 100 · Polishability 60 / 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 scale4027

4027-N vs 4027-QT315 — frequently asked

Is 4027-QT315 stronger than 4027-N?

Yes. 4027-QT315 has a typical yield strength of 760 MPa (110 ksi) against 415 MPa (60.2 ksi) for 4027-N — about 83% more. Tensile strength is 950 MPa (138 ksi) vs 655 MPa (95 ksi).

Which condition does FabDigit quote by default, N or QT315?

A is the default 4027 condition in the FabDigit quote flow (neither N nor QT315). 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, 4027-N or 4027-QT315?

4027-N. Its machinability rates good (58/100) against fair (42/100) for 4027-QT315; for welding the order is 4027-N first (good, 60/100) then 4027-QT315 (fair, 42/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4027-N and 4027-QT315 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.