| 摘要 |
<p>1527449 Making ferrous martensitic sintered bodies FORD MOTOR CO Ltd 14 June 1977 [26 Oct 1976] 24766/77 Heading C7D A ferrous based compact with a martensitic structure is made by impacting the ferrous particles at ambient temperature e.g. in a ball mill, with Fe or Cu balls at least 50 times larger than the particles to cold work the particles and cool them with Cu or Fe. The coated particles are then compacted and sintered e.g. at 2000-2100‹F. The particles used are preferably machine turnings which are heat treated to form at least 80% martensitic structure and then milled to chips of -30 mesh. The Fe or Cu balls used in impacting are at least 0À1 inch diameter.</p> |
