C90700 Gear Bronze is a hard, strong alloy with good corrosion resistance, especially in seawater. As a bearing material it resists both wear and fatigue applications. It is moderately machinable. C 907 is widely used for gears and worm wheels, bearings, marine fittings, piston rings and pump components.
Weight % | Cu(1)(2) | Sn | Pb | Zn | Fe | Sb | Ni+Co | S | P(3) | Al | Si | Mn |
---|---|---|---|---|---|---|---|---|---|---|---|---|
minimum | 88.0 | 10.0 | — | — | — | — | — | — | — | — | — | — |
maximum | 90.0 | 12.0 | .50 | .50 | .15 | .20 | .50 | .05 | .30 | .005 | .005 | — |
(1) Cu + sum of named elements, 99.4% min.
(2) In determining Cu-min., Cu may be calculated as Cu + Ni.
(3) For continuous castings, P shall be 1.5% max.
Characteristics | English | Metric | |
---|---|---|---|
Nominal density | 20°C / 68°F | 0.317 lbs/in3 | 8.77 g/cm3 |
Melting range | Liquidus | 1830 °F | 999 °C |
Solidus | 1528 °F | 831 °C | |
Specific heat | 20°C / 68°F | 0.09 BTU/lb – °F | 377 J/KG- °K |
Coefficient of
thermal expansion |
68°F – 392°F
20°C – 200°C |
10.2 micro in/in- °F | 18.4 micro m/m- °K |
Thermal conductivity | 20°C / 68°F | 40.8 BTU/ft- hr – °F | 70.6 W/m – °K |
Electrical resistivity | 20°C / 68°F | 15 nΩ ∙ m | |
Electrical conductivity | Volumetric:
20°C / 68°F |
10% IACS |
Temper | Tensile | Hardness | ||||
---|---|---|---|---|---|---|
Ultimate | Yield | Elongation in 50 mm
(2 in.) |
Rockwell B | |||
KSI | MPa | KSI | MPa | % | ||
As cast | 303 | 44 | 152 | 22 | 20 | 47 |
Heat treated | 379 | 55 | 207 | 30 | 16 | 65 |
Centrifugal / Sand Castings | Continuous Castings | Ingot |
---|---|---|
ASTM – B427 | ASTM – B504 | ASTM – B30 |