| 摘要 |
<p>This invention relates to a hard metal wearing piece, especially for tools, which is covered at least on the places subjected to wear with stratified protecting coating. This stratified protecting coating comprises at least five superimposed layers, at least two of them being of different compositions; furthermore, the internal layer in contact with the substrate is a layer of carbide, the external layer is a layer of boride or carbide, and the intermediary layers are of carbide, nitride, oxide, boride, and/or of mixed compounds thereof.</p> |
