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Steel S700MC vs X65

Steel · grade comparison

Steel S700MC and X65 are both steel grades. S700MC is the stronger of the two: yield strength 740 MPa (107 ksi) against 495 MPa (71.8 ksi) for X65, about 49% more; tensile strength follows at 810 MPa (117 ksi) vs 570 MPa (82.7 ksi). In exchange, X65 is the more ductile: elongation 32% versus 14% for S700MC, and S700MC is harder (245 HB vs 180 HB). S700MC runs hotter in service (300°C vs 250°C continuous) and X65 conducts heat better (47 W/m·K vs 40 W/m·K). On the shop floor, X65 machines more easily (good vs fair) and X65 sits in a lower cost tier (budget, $) than S700MC (standard, $$).

S700MCChoose it when strength drives the design, or when the part sees heat.

X65Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

S700MC vs X65: properties

S700MCX65

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
207 GPa30 Msi

Shear Modulus

81 GPa11.7 Msi
80 GPa11.6 Msi

Poisson's Ratio

0.3
0.29

Tensile Strength (Ultimate)

810 MPa117 ksi
570 MPa82.7 ksi

Yield Strength (0.2% offset)

740 MPa107 ksi
495 MPa71.8 ksi

Elongation at Break

14%
32%

Reduction in Area

55%
68%

Compressive Strength

740 MPa107 ksi
495 MPa71.8 ksi

Shear Strength

490 MPa71.1 ksi
350 MPa50.8 ksi

Fatigue Strength (Endurance Limit)

360 MPa52.2 ksi
270 MPa39.2 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
200 MPa·√m182 ksi·√in

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
260 J192 ft·lbf

Hardness, Brinell

245 HB
180 HB

Hardness, Rockwell B

100 HRB
89 HRB

Hardness, Rockwell C

23 HRC
—

Hardness, Vickers

255 HV
190 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,460°C2,660 °F
1,425°C2,597 °F

Liquidus Temperature

1,510°C2,750 °F
1,505°C2,741 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³

Thermal

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

Thermal Conductivity

40 W/m·K23.1 BTU/hr·ft·°F
47 W/m·K27.2 BTU/hr·ft·°F

Max Service Temperature (continuous)

300°C572 °F
250°C482 °F

Min Service Temperature

-40°C-40 °F
-45°C-49 °F

Same in both: Specific Heat Capacity 470 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 270 J/g116 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
8.6 % IACS

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
2×10⁻⁷ Ω·m7.87 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.62 V
-0.68 V

Same in both: Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

45 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
60%

Weldability

85 / 100
90 / 100

Formability (cold)

65 / 100
70 / 100

Brazeability / Solderability

50 / 100
45 / 100

Polishability

50 / 100
40 / 100

Sustainability

Primary-production footprint per kilogram.

Typical Recycled Content

25%
20%

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 40 L/kg4.8 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

103 kN·m/kg
73 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.4 MN·m/kg

Modulus of Resilience

1,304 kJ/m³
592 kJ/m³

Thermal Diffusivity

10.8 mm²/s
12.7 mm²/s

Thermal Shock Resistance Index

13
11

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 scaleS700MCX65

Manufacturing and finishing

CapabilityS700MCX65
Sheet metalYes—
Default conditionTMCP—
Relative cost$$ Standard$ Budget
Min. machined wall——
Best machined surface——
Black OxideYes—
CerakoteYes—
Chrome PlatingYes—
E-CoatingYes—
Hot-Dip GalvanizingYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—
Powder CoatingYes—
Tin PlatingYes—
Zinc PlatingYes—
Zinc-Flake (Dip-Spin) CoatingYes—
Zinc-Nickel PlatingYes—

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

S700MC vs X65 — frequently asked

Is S700MC stronger than X65?

Yes. S700MC has a typical yield strength of 740 MPa (107 ksi) against 495 MPa (71.8 ksi) for X65 — about 49% more. Tensile strength is 810 MPa (117 ksi) vs 570 MPa (82.7 ksi).

Which is cheaper, S700MC or X65?

X65 is the lower-cost material: it sits in the budget tier ($) while S700MC is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, S700MC or X65?

X65. Its machinability rates good (55/100) against fair (45/100) for S700MC; for welding the order is X65 first (excellent, 90/100) then S700MC (excellent, 85/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in S700MC and X65 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.