| 摘要 |
Method of dimensionally stabilizing the interface between metal parts (26,27,28) of differing thermal expansion characteristics (TEC), regardless of temperature variations under normal designed use of such parts, comprising: (a) hot extruding a mixture of ceramic fibers (34) (i.e., Si3N4, SiC, Al2O3) and a powder of the metal having the higher TEC (i.e., Al, Ti, Mg) while aligning the fibers (34) generally along the direction of extrusion, to form an insert (32); (b) shaping said insert (32) to align its fibers generally in at least one direction of anticipated thermal growth that may interfere with the interface; (c) casting the insert in place within a first part (27,28) comprised of the higher TEC metal and with the insert's fibers (i) oriented as above, and (ii) preheated to a temperature no greater than 35-45% of the temperature of the molten light metal; and (d) bringing together the first metal part (27,28) with a second part (26) of lower TEC metal (i.e., Fe or steel) to form the interface. The insert (32) may be located in a mould in a manner to be totally enveloped by the molten light metal with the insert having a surface spaced a uniform, predetermined distance from the exterior of the cast light metal part, or the insert may be located to expose a surface thereof upon completion of the casting. |
