C87500 / CDA 875 Copper and silicon bronze alloys
Casting standards :
| ASTM (B Series) | B584 |
| SAE (J Series) | J462 |
| Federal (QQ-C- Series) | 390 |
Composition of specifications :
| Minimum | Maximum | |
| Copper (Cu) | 79 | |
| Lead (Pb) | 0.5 | |
| Zinc (Zn) | 12 | 16 |
| Aluminum (Al) | – | 0.5 |
| Silicon (Si) | 3 | 5 |
| Copper + sum of named elements | 99.5 | 5 |
Properties of specifications :
| Heat treatment “F” indicates a melt | Heat treatment status | Minimum |
| Tensile strength (ksi) | F | 60 |
| Yield strength (0.5% extension under load) (ksi) | F | 24 |
typical properties :
| Heat treatment status | Typical | |
| Area reduction (%) | 20 | |
| Elasticity module (ksi) | 15400 | |
| Hardness (Brinell) (HB @ 500kg) | 115 | |
| Machinability (% of free cut brass) | 50 | |
| Fatigue strength (10 ^ 8 cycles) (ksi) | 22 | |
| Fatigue strength (10 ^ 8 cycles) (ft-lb) | 32 | |
| Compressive strength (0.001 in. set/in.) (ksi) | 26.5 | |
| Compressive strength (0.010 in. set/in.) (ksi) | 43 | |
| Compressive strength (0.100 in. set/in.) (ksi) | 75 | |
| Creep Strength (0.00001% per hour) (ksi) | 28 @ 350F | |
| Melting range (Liquidus-Solidus)(F) | 1510-1683 | |
| Coefficient of thermal expansion (per F @ 68-400F) | 0.0000109 | |
| Thermal conductivity (Btu/sq.ft/ft./hr/F @ 68F) | 16 | |
| Specific heat(Btu/lb/F @ 68F) | 0.09 | |
| Electrical conductivity (% IACS @ 68F) | 6.7 | |
| Density(lb/cu.in. @ 68F) | 0.299 | |
| Casting temperature (Light castings) (F) | 1900-2000 | |
| Casting Temperature (Heavy Castings) (F) | 1800-1900 | |
| Shrinking model makers (in/ft) | 15/64 | |
| Slag | Low | |
| Gassing | Medium | |
| Fluidity | High | |
| Elongation (2 inch gauge length) (%) | F | 17 |