| 摘要 |
PCT No. PCT/GB87/00830 Sec. 371 Date Jul. 21, 1989 Sec. 102(e) Date Jul. 21, 1989 PCT Filed Nov. 20, 1987 PCT Pub. No. WO88/03961 PCT Pub. Date Jun. 2, 1988.Sintered ferrous alloys of at least 90% theoretical density are obtained by sintering a powder mixture containing atomized copper-free ferrous slloy, copper phosphide and, optionally, copper, copper alloy and/or graphite to provide a sintered alloy containing, in percentages by weight, 0.6-2.5% carbon, 2-8% chromium, 4.2-20% copper, 0.5-10% molybdenum, 0.4-1.2 % phosphorus, 1-20% tungsten, 1-5% vanadium, and optionally, up to 12% cobalt, up to 2% manganese and up to 2% nickel and the balance being iron and less than 2% impurities. The % carbon content is in the range CCC % -0.1% to CCC % +0.3% (where CCC % is the calculated carbon content =(CWE/20)-0.4 and CWE=% tungsten content +twice % molybdenum content +six times % vanadium content) and the copper phosphide contains 2 to 14% phosphorus. The sintered compact is cooled at a rate which prevents hardening and can subsequently be machined and/or heat treated.
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