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Steel 100CrMnSi6-4 +AR vs 100CrMnSi6-4 +QT 60-64HRC

Steel · 100CrMnSi6-4 temper comparison

100CrMnSi6-4 +AR and 100CrMnSi6-4 +QT 60-64HRC are two conditions of the same steel grade, 100CrMnSi6-4: +AR (hot rolled) versus +QT 60-64HRC (hardened and tempered). The chemistry is identical, so every difference below comes from the condition. 100CrMnSi6-4 +QT 60-64HRC is the stronger of the two: yield strength 1,900 MPa (276 ksi) against 520 MPa (75.4 ksi) for 100CrMnSi6-4 +AR, about 3.7 times as much; tensile strength follows at 2,200 MPa (319 ksi) vs 950 MPa (138 ksi). In exchange, 100CrMnSi6-4 +AR is the more ductile: elongation 12% versus 1% for 100CrMnSi6-4 +QT 60-64HRC, and 100CrMnSi6-4 +AR is harder (280 HB vs 195 HB). 100CrMnSi6-4 +AR runs hotter in service (200°C vs 120°C continuous) and 100CrMnSi6-4 +AR conducts heat better (41 W/m·K vs 35 W/m·K). On the shop floor, 100CrMnSi6-4 +AR machines more easily (poor vs not recommended).

100CrMnSi6-4 +ARChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

100CrMnSi6-4 +QT 60-64HRCChoose it when strength drives the design.

100CrMnSi6-4 +AR vs 100CrMnSi6-4 +QT 60-64HRC: properties

100CrMnSi6-4 +AR100CrMnSi6-4 +QT 60-64HRC

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

950 MPa138 ksi
2,200 MPa319 ksi

Yield Strength (0.2% offset)

520 MPa75.4 ksi
1,900 MPa276 ksi

Elongation at Break

12%
1%

Reduction in Area

25%
40%

Compressive Strength

560 MPa81.2 ksi
2,400 MPa348 ksi

Shear Strength

600 MPa87 ksi
1,300 MPa189 ksi

Fatigue Strength (Endurance Limit)

420 MPa60.9 ksi
800 MPa116 ksi

Charpy V-Notch Impact (RT)

10 J7.4 ft·lbf
4 J3 ft·lbf

Hardness, Brinell

280 HB
195 HB

Hardness, Rockwell B

105 HRB
92 HRB

Hardness, Vickers

295 HV
760 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 166 GPa24.1 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.81 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,450°C2,642 °F

Thermal

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

Thermal Conductivity

41 W/m·K23.7 BTU/hr·ft·°F
35 W/m·K20.2 BTU/hr·ft·°F

Max Service Temperature (continuous)

200°C392 °F
120°C248 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -50°C-58 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

2.6×10⁻⁷ Ω·m10.2 µΩ·in
2.5×10⁻⁷ Ω·m9.84 µΩ·in

Same in both: Electrical Conductivity 7 % IACS

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

30 / 100
8 / 100

Machinability Rating (AISI 1212 = 100 %)

25%
5%

Weldability

8 / 100
3 / 100

Formability (cold)

15 / 100
2 / 100

Polishability

85 / 100
90 / 100

Same in both: Brazeability / Solderability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.3 kg CO₂/kg · Embodied Water 60 L/kg7.2 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 scale100CrMnSi6-4

100CrMnSi6-4 +AR vs 100CrMnSi6-4 +QT 60-64HRC — frequently asked

Is 100CrMnSi6-4 +QT 60-64HRC stronger than 100CrMnSi6-4 +AR?

Yes. 100CrMnSi6-4 +QT 60-64HRC has a typical yield strength of 1,900 MPa (276 ksi) against 520 MPa (75.4 ksi) for 100CrMnSi6-4 +AR — about 3.7 times as much. Tensile strength is 2,200 MPa (319 ksi) vs 950 MPa (138 ksi).

Which condition does FabDigit quote by default, +AR or +QT 60-64HRC?

+AC is the default 100CrMnSi6-4 condition in the FabDigit quote flow (neither +AR nor +QT 60-64HRC). 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, 100CrMnSi6-4 +AR or 100CrMnSi6-4 +QT 60-64HRC?

100CrMnSi6-4 +AR. Its machinability rates poor (30/100) against not recommended (8/100) for 100CrMnSi6-4 +QT 60-64HRC; for welding the order is 100CrMnSi6-4 +AR first (not recommended, 8/100) then 100CrMnSi6-4 +QT 60-64HRC (not recommended, 3/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 100CrMnSi6-4 +AR and 100CrMnSi6-4 +QT 60-64HRC 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.