Copper Alloy C85900-M02 vs C85900-M04
Copper Alloy · C85900 temper comparison
C85900-M02 and C85900-M04 are two conditions of the same copper alloy grade, C85900: M02 (as centrifugally cast) versus M04 (as pressure die cast). The chemistry is identical, so every difference below comes from the condition. C85900-M04 is the stronger of the two: yield strength 195 MPa (28.3 ksi) against 125 MPa (18.1 ksi) for C85900-M02, about 56% more; tensile strength follows at 370 MPa (53.7 ksi) vs 310 MPa (45 ksi). In exchange, C85900-M02 is the more ductile: elongation 25% versus 15% for C85900-M04, and C85900-M04 is harder (85 HB vs 65 HB). On the shop floor, C85900-M02 welds better (30 vs 20 out of 100).
C85900-M02Choose it when the part is bent, formed or impact-loaded, or when it will be welded.
C85900-M04Choose it when strength drives the design.
C85900-M02 vs C85900-M04: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all copper alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all copper alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
Same in both: Shear Modulus 37 GPa5.4 Msi · Bulk Modulus 101 GPa14.6 Msi · Poisson's Ratio 0.34
Physical
Density and transition temperatures.
Same in both: Density 8.4 g/cm³0.3 lb/in³ · Melting Point (Solidus) 875°C1,607 °F · Liquidus Temperature 930°C1,706 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Same in both: Specific Heat Capacity 380 J/kg·K0.09 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 21 µm/m·K11.7 µin/in·°F · Latent Heat of Fusion 165 J/g70.9 BTU/lb · Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -100°C-148 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.25 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Castability 85 / 100 · Brazeability / Solderability 85 / 100 · Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 45 MJ/kg19,347 BTU/lb · Embodied Carbon (primary production) 3.2 kg CO₂/kg · Embodied Water 250 L/kg30 gal/lb · Typical Recycled Content 90%
Strength versus weight
Yield strength against density for every copper alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
C85900-M02 vs C85900-M04 — frequently asked
Is C85900-M04 stronger than C85900-M02?
Yes. C85900-M04 has a typical yield strength of 195 MPa (28.3 ksi) against 125 MPa (18.1 ksi) for C85900-M02 — about 56% more. Tensile strength is 370 MPa (53.7 ksi) vs 310 MPa (45 ksi).
Which condition does FabDigit quote by default, M02 or M04?
M01 is the default C85900 condition in the FabDigit quote flow (neither M02 nor M04). 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, C85900-M02 or C85900-M04?
C85900-M02, by a small margin. Both rate very good for machinability — 80/100 against 75/100 for C85900-M04; for welding the order is C85900-M02 first (poor, 30/100) then C85900-M04 (poor, 20/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in C85900-M02 and C85900-M04 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.