| 摘要 |
A composite lightweight engine poppet valve (10, 110, 210) that has a valve head portion (12, 112, 212) and at least a portion of the stem portion (14, 114, 214) made from a titanium intermetallic material attached by way of a solid state attachment to a nickel base alloy transition piece (16, 116, 216) that is heat treated for high creep resistance. The tip portion (18, 118, 218) made from conventional material is first attached to one end of the transition piece. The transition piece (16, 116, 216) is cut to a desired length and then attached preferably by friction welding to the titanium intermetallic stem portion (14, 114, 214) at a preselected distance (d1, d2, or d3). The tip portion (18, 118, 218) made from conventional material is then attached to the other end of the transition piece. In another embodiment, a second hollow stem portion (215) is attached to the transition piece (216) and the tip portion (218) is then attached thereto.
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