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Steel P3 vs P6

Steel · grade comparison

Steel P3 and P6 are both steel grades. P6 is the stronger of the two: yield strength 415 MPa (60.2 ksi) against 340 MPa (49.3 ksi) for P3, about 22% more; tensile strength follows at 655 MPa (95 ksi) vs 540 MPa (78.3 ksi). In exchange, P3 is the more ductile: elongation 28% versus 20% for P6, and P6 is harder (195 HB vs 160 HB). P3 runs hotter in service (400°C vs 300°C continuous) and P3 conducts heat better (40 W/m·K vs 34 W/m·K).

P3Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

P6Choose it when strength drives the design.

P3 vs P6: properties

P3P6

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

540 MPa78.3 ksi
655 MPa95 ksi

Yield Strength (0.2% offset)

340 MPa49.3 ksi
415 MPa60.2 ksi

Elongation at Break

28%
20%

Reduction in Area

60%
55%

Compressive Strength

345 MPa50 ksi
420 MPa60.9 ksi

Shear Strength

350 MPa50.8 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

250 MPa36.3 ksi
300 MPa43.5 ksi

Fracture Toughness (K_IC)

110 MPa·√m100 ksi·√in
95 MPa·√m86.5 ksi·√in

Charpy V-Notch Impact (RT)

110 J81.1 ft·lbf
90 J66.4 ft·lbf

Hardness, Brinell

160 HB
195 HB

Hardness, Rockwell B

84 HRB
92 HRB

Hardness, Vickers

—
205 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Liquidus Temperature

1,500°C2,732 °F
1,490°C2,714 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F

Thermal

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

Thermal Conductivity

40 W/m·K23.1 BTU/hr·ft·°F
34 W/m·K19.6 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

11.9 µm/m·K6.6 µin/in·°F
11.8 µm/m·K6.6 µin/in·°F

Latent Heat of Fusion

270 J/g116 BTU/lb
250 J/g107 BTU/lb

Max Service Temperature (continuous)

400°C752 °F
300°C572 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8.5 % IACS
—

Electrical Resistivity

2×10⁻⁷ Ω·m7.87 µΩ·in
3×10⁻⁷ Ω·m11.8 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability Rating (AISI 1212 = 100 %)

65%
70%

Weldability

65 / 100
60 / 100

Castability

35 / 100
40 / 100

Polishability

50 / 100
60 / 100

Same in both: Machinability 62 / 100 · Formability (cold) 70 / 100 · Brazeability / Solderability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

30 MJ/kg12,898 BTU/lb
34 MJ/kg14,617 BTU/lb

Embodied Carbon (primary production)

2.2 kg CO₂/kg
2.4 kg CO₂/kg

Embodied Water

50 L/kg6 gal/lb
60 L/kg7.2 gal/lb

Typical Recycled Content

30%
45%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

69 kN·m/kg
83 kN·m/kg

Modulus of Resilience

282 kJ/m³
420 kJ/m³

Thermal Diffusivity

11.1 mm²/s
9.4 mm²/s

Same in both: Specific Stiffness (E / density) 26.1 MN·m/kg · Thermal Shock Resistance Index 9

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 scaleP3P6

Manufacturing and finishing

CapabilityP3P6
Default condition——
Relative cost$$ Standard$$ Standard
Min. machined wall——
Best machined surface——

Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

P3 vs P6 — frequently asked

Is P6 stronger than P3?

Yes. P6 has a typical yield strength of 415 MPa (60.2 ksi) against 340 MPa (49.3 ksi) for P3 — about 22% more. Tensile strength is 655 MPa (95 ksi) vs 540 MPa (78.3 ksi).

Which is cheaper, P3 or P6?

Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which welds better, P3 or P6?

P3. Its weldability rates good (65/100) against good (60/100) for P6.

Ready to make it?

Upload a CAD file and FabDigit prices the part in P3 and P6 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.