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Steel 18Kh2N4MA-N vs 18Kh2N4MA-QT500

Steel · 18Kh2N4MA temper comparison

18Kh2N4MA-N and 18Kh2N4MA-QT500 are two conditions of the same steel grade, 18Kh2N4MA: N (normalized) versus QT500 (Q&T 500–560). The chemistry is identical, so every difference below comes from the condition. 18Kh2N4MA-N is the stronger of the two: tensile strength 1,200 MPa (174 ksi) against 1,030 MPa (149 ksi) for 18Kh2N4MA-QT500, about 17% more. In exchange, 18Kh2N4MA-QT500 is the more ductile: elongation 16% versus 12% for 18Kh2N4MA-N, and 18Kh2N4MA-N is harder (350 HB vs 310 HB). 18Kh2N4MA-QT500 runs hotter in service (400°C vs 200°C continuous).

18Kh2N4MA-NChoose it when strength drives the design.

18Kh2N4MA-QT500Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

18Kh2N4MA-N vs 18Kh2N4MA-QT500: properties

18Kh2N4MA-N18Kh2N4MA-QT500

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

1,200 MPa174 ksi
1,030 MPa149 ksi

Yield Strength (0.2% offset)

900 MPa131 ksi
880 MPa128 ksi

Elongation at Break

12%
16%

Reduction in Area

48%
62%

Compressive Strength

930 MPa135 ksi
1,000 MPa145 ksi

Shear Strength

720 MPa104 ksi
750 MPa109 ksi

Fatigue Strength (Endurance Limit)

530 MPa76.9 ksi
480 MPa69.6 ksi

Fracture Toughness (K_IC)

65 MPa·√m59.2 ksi·√in
105 MPa·√m95.6 ksi·√in

Charpy V-Notch Impact (RT)

60 J44.3 ft·lbf
130 J95.9 ft·lbf

Hardness, Brinell

350 HB
310 HB

Hardness, Rockwell C

37 HRC
32 HRC

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 163 GPa23.6 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 1,490°C2,714 °F

Thermal

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

Max Service Temperature (continuous)

200°C392 °F
400°C752 °F

Same in both: Thermal Conductivity 33 W/m·K19.1 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.5 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -70°C-94 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Resistivity 3.5×10⁻⁷ Ω·m13.8 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 14 / 100

Manufacturability

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

Machinability

19 / 100
28 / 100

Machinability Rating (AISI 1212 = 100 %)

16%
27%

Weldability

24 / 100
22 / 100

Formability (cold)

16 / 100
18 / 100

Same in both: Brazeability / Solderability 45 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 36 MJ/kg15,477 BTU/lb · Embodied Carbon (primary production) 2.7 kg CO₂/kg · Embodied Water 70 L/kg8.4 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 scale18Kh2N4MA

18Kh2N4MA-N vs 18Kh2N4MA-QT500 — frequently asked

Is 18Kh2N4MA-N stronger than 18Kh2N4MA-QT500?

Yes. 18Kh2N4MA-N has a typical tensile strength of 1,200 MPa (174 ksi) against 1,030 MPa (149 ksi) for 18Kh2N4MA-QT500 — about 17% more.

Which condition does FabDigit quote by default, N or QT500?

QT200 is the default 18Kh2N4MA condition in the FabDigit quote flow (neither N nor QT500). 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, 18Kh2N4MA-N or 18Kh2N4MA-QT500?

18Kh2N4MA-QT500, by a small margin. Both rate poor for machinability — 28/100 against 19/100 for 18Kh2N4MA-N.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 18Kh2N4MA-N and 18Kh2N4MA-QT500 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.