| 摘要 |
Aluminium base alloys for use as the bearing layer of a bearing made from a bi-metallic strip comprise (a) 3% cadmium, 1% copper, 1% nickel, remainder aluminium, (b) 4% silicon, 1% cadmium. remainder aluminium, (c) 5%-7% tin, 1% copper, 1.5% silicon, 0.5% nickel, remainder aluminium, (d) 15%-30% tin (usually 17.5% to 22.5%) 1% copper, 0.3% impurities, remainder aluminium. Cobalt plating. Steel strip is plated with cobalt electrolytically in a bath comprising 504 grams/litre of cobalt sulphat, 17 grams/litre of sodium chloride and 45 grams/litre of boric acid. The solution has a pH of about 5.2 and may be used at 75 DEG F. A period of about 85 seconds at a current density of 40 amps/ft2 deposits 0.00005 inches of cobalt. Cobalt-phosphorus is plated on the steel strip in a solution containing 30 grams/litre cobalt chloride, 10 grams/litre sodium hypophosphite, 50 grams/litre ammonium chloride and 100 grams/litre sodium citrate. The solution has a pH of between about 8 to 9 and at a temperature of 195 DEG F about 5 minutes immersion is required for a deposit of 0.00005 inches. |
