| 摘要 |
Process for the manufacture of sintered articles made of fast steel of good compactness and having good frictional properties. This process of manufacture comprises the following stages: a) the starting powders are supplied: a1) prealloyed steel (C 0.6 to 1.5, W 1 to 17, Mo 0.1 to 10, Cr 3 to 15, V 0.5 to 6, Co < 15 %, Cu < 15 %, impurities and Fe: the remainder) a2) a powder of an alloy belonging to the group (cuprophosphorus, ferroboron) giving, in the case of the charge, an overall content of 0.7 to 1.5 % of metalloid element P or B a3) optionally graphite, the overall content of the charge being between 0.6 and 2.5 % a4) optionally additives (solid lubricant and/or cutting additive), b) these powders are mixed and c) they are compressed into the form of articles d) the articles are sintered under neutral gas at a temperature of between 1080 and 1160 DEG C e) they are cooled at at least 40 DEG C/min between the sintering temperature and 500 DEG C. The articles obtained are characterised by their composition, their structure, their compactness and their hardness. They are typically cold and/or hot rubbing components (temperature </= approximately 850 DEG C) such as: cams, skids, pump vanes, valve seats.
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