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Steel CPM M4-ANN vs CPM M4 HT-CRYO

Steel · CPM M4 temper comparison

CPM M4-ANN and CPM M4 HT-CRYO are two conditions of the same steel grade, CPM M4: ANN (annealed) versus HT-CRYO (hardened, cryogenically treated and multiple tempered, 64–66 HRC). The chemistry is identical, so every difference below comes from the condition. CPM M4 HT-CRYO is the stronger of the two: yield strength 2,100 MPa (305 ksi) against 550 MPa (79.8 ksi) for CPM M4-ANN, about 3.8 times as much; tensile strength follows at 2,300 MPa (334 ksi) vs 850 MPa (123 ksi). In exchange, CPM M4-ANN is the more ductile: elongation 12% versus 0.5% for CPM M4 HT-CRYO, and CPM M4 HT-CRYO is harder (740 HB vs 241 HB). CPM M4-ANN conducts electricity better (3.1 % IACS vs 2.5 % IACS). On the shop floor, CPM M4-ANN machines more easily (poor vs not recommended) and CPM M4-ANN welds better (poor vs not recommended).

CPM M4-ANNChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

CPM M4 HT-CRYOChoose it when strength drives the design.

CPM M4-ANN vs CPM M4 HT-CRYO: properties

CPM M4-ANNCPM M4 HT-CRYO

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

221 GPa32.1 Msi
225 GPa32.6 Msi

Tensile Strength (Ultimate)

850 MPa123 ksi
2,300 MPa334 ksi

Yield Strength (0.2% offset)

550 MPa79.8 ksi
2,100 MPa305 ksi

Elongation at Break

12%
0.5%

Reduction in Area

22%
0.5%

Compressive Strength

900 MPa131 ksi
4,200 MPa609 ksi

Shear Strength

520 MPa75.4 ksi
1,400 MPa203 ksi

Fatigue Strength (Endurance Limit)

380 MPa55.1 ksi
900 MPa131 ksi

Fracture Toughness (K_IC)

45 MPa·√m41 ksi·√in
19 MPa·√m17.3 ksi·√in

Charpy V-Notch Impact (RT)

22 J16.2 ft·lbf
5 J3.7 ft·lbf

Hardness, Brinell

241 HB
740 HB

Hardness, Rockwell C

23 HRC
65 HRC

Hardness, Vickers

253 HV
830 HV

Same in both: Shear Modulus 84 GPa12.2 Msi · Bulk Modulus 168 GPa24.4 Msi · Poisson's Ratio 0.28 · Hardness, Rockwell B 99 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.97 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,250°C2,282 °F · Liquidus Temperature 1,400°C2,552 °F

Thermal

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

Thermal Conductivity

24 W/m·K13.9 BTU/hr·ft·°F
22 W/m·K12.7 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.2 µm/m·K6.2 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 540°C1,004 °F · Min Service Temperature -50°C-58 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

3.1 % IACS
2.5 % IACS

Electrical Resistivity

5.6×10⁻⁷ Ω·m22 µΩ·in
6.9×10⁻⁷ Ω·m27.2 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

18 / 100
20 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.5 V

Manufacturability

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

Machinability

25 / 100
4 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
3%

Weldability

20 / 100
5 / 100

Formability (cold)

14 / 100
1 / 100

Same in both: Brazeability / Solderability 45 / 100 · Polishability 65 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 75 MJ/kg32,244 BTU/lb · Embodied Carbon (primary production) 5.2 kg CO₂/kg · Embodied Water 110 L/kg13.2 gal/lb · Typical Recycled Content 20%

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 scaleCPM M4

CPM M4-ANN vs CPM M4 HT-CRYO — frequently asked

Is CPM M4 HT-CRYO stronger than CPM M4-ANN?

Yes. CPM M4 HT-CRYO has a typical yield strength of 2,100 MPa (305 ksi) against 550 MPa (79.8 ksi) for CPM M4-ANN — about 3.8 times as much. Tensile strength is 2,300 MPa (334 ksi) vs 850 MPa (123 ksi).

Which condition does FabDigit quote by default, ANN or HT-CRYO?

ANN is the default CPM M4 condition in the FabDigit quote flow. 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, CPM M4-ANN or CPM M4 HT-CRYO?

CPM M4-ANN. Its machinability rates poor (25/100) against not recommended (4/100) for CPM M4 HT-CRYO; for welding the order is CPM M4-ANN first (poor, 20/100) then CPM M4 HT-CRYO (not recommended, 5/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in CPM M4-ANN and CPM M4 HT-CRYO 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.