发明名称 |
METHOD OF MANUFACTURING AN ALUMINIUM PISTON WITH A HARD OXIDE COATED HEAD |
摘要 |
<p>For a piston consisting of an Al-Si alloy having a mean linear grain diameter of the Silicon eutectic of more than 3 mu m for combustion engines and provided with a hard-oxidized top, the structure of the base material to be oxidized is subjected to a grain refinement in the depth to be oxidized so that the silicon eutectic has a mean linear grain diameter of less than 3 mu m, preferably less than 2.5 mu m. By this means, the resistance to erosion of the hard-oxide layer is improved. The grain refinement may be effected in the respective zones during the casting of the piston or thereafter by re-melting those zones prior to oxidizing. If the risk of erosion exists only in specific locally limited zones of a relatively large hard-oxide surface, then a grain refinement confined to these zones is sufficient.</p> |
申请公布号 |
EP0062173(B1) |
申请公布日期 |
1988.06.08 |
申请号 |
EP19820101945 |
申请日期 |
1982.03.11 |
申请人 |
MAHLE GMBH |
发明人 |
HERRMANN, RUDIGER;SCHLOSSER, DETLEF, DIPL.-ING.;WIMMER, HEINZ |
分类号 |
C22F1/043;C22C21/02;C22C21/04;C22F1/04;F02B3/06;F02F3/00;F02F3/12;(IPC1-7):F02F3/12;C22F3/00;C23C8/10 |
主分类号 |
C22F1/043 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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