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Steel M7-ANN vs M7 CD-ANN

Steel · M7 temper comparison

M7-ANN and M7 CD-ANN are two conditions of the same steel grade, M7: ANN (annealed) versus CD-ANN (cold drawn / centreless ground, annealed). The chemistry is identical, so every difference below comes from the condition. M7 CD-ANN is the stronger of the two: yield strength 600 MPa (87 ksi) against 520 MPa (75.4 ksi) for M7-ANN, about 15% more; tensile strength follows at 880 MPa (128 ksi) vs 830 MPa (120 ksi). In exchange, M7-ANN is the more ductile: elongation 18% versus 14% for M7 CD-ANN.

M7-ANNChoose it when the part is bent, formed or impact-loaded.

M7 CD-ANNChoose it when strength drives the design.

M7-ANN vs M7 CD-ANN: properties

M7-ANNM7 CD-ANN

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

830 MPa120 ksi
880 MPa128 ksi

Yield Strength (0.2% offset)

520 MPa75.4 ksi
600 MPa87 ksi

Elongation at Break

18%
14%

Reduction in Area

30%
25%

Compressive Strength

1,600 MPa232 ksi
1,700 MPa247 ksi

Shear Strength

520 MPa75.4 ksi
550 MPa79.8 ksi

Fatigue Strength (Endurance Limit)

380 MPa55.1 ksi
400 MPa58 ksi

Fracture Toughness (K_IC)

40 MPa·√m36.4 ksi·√in
38 MPa·√m34.6 ksi·√in

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
16 J11.8 ft·lbf

Hardness, Brinell

235 HB
245 HB

Hardness, Rockwell B

99 HRB
100 HRB

Hardness, Vickers

248 HV
258 HV

Same in both: Elastic (Young's) Modulus 207 GPa30 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 7.95 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,250°C2,282 °F · Liquidus Temperature 1,430°C2,606 °F

Thermal

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

Same in both: Thermal Conductivity 24 W/m·K13.9 BTU/hr·ft·°F · Specific Heat Capacity 420 J/kg·K0.1 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.9 µm/m·K6.1 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 500°C932 °F · Min Service Temperature -60°C-76 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 3.1 % IACS · Electrical Resistivity 5.5×10⁻⁷ Ω·m21.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.55 V · Corrosion Resistance 18 / 100

Manufacturability

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

Machinability

32 / 100
30 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
42%

Formability (cold)

15 / 100
12 / 100

Same in both: Weldability 12 / 100 · Castability 25 / 100 · Brazeability / Solderability 45 / 100 · Polishability 65 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 44 MJ/kg18,917 BTU/lb · Embodied Carbon (primary production) 3.3 kg CO₂/kg · Embodied Water 70 L/kg8.4 gal/lb · Typical Recycled Content 40%

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 scaleM7

M7-ANN vs M7 CD-ANN — frequently asked

Is M7 CD-ANN stronger than M7-ANN?

Yes. M7 CD-ANN has a typical yield strength of 600 MPa (87 ksi) against 520 MPa (75.4 ksi) for M7-ANN — about 15% more. Tensile strength is 880 MPa (128 ksi) vs 830 MPa (120 ksi).

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

ANN is the default M7 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.

When should I choose M7-ANN over M7 CD-ANN?

Pick M7-ANN when the part is bent, formed or impact-loaded. Pick M7 CD-ANN when strength drives the design.

Ready to make it?

Upload a CAD file and FabDigit prices the part in M7-ANN and M7 CD-ANN 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.