Cu含量和烧结温度对Fe-Cu基粉末冶金复合材料摩擦磨损性能的影响

Effect of Copper Content and Sintering Temperature on Friction and Wear Properties of Powder-metallurgical Fe-Cu Based Composites

研究了铜含量和烧结温度对Fe-Cu基粉末冶金复合材料摩擦磨损性能影响。结果表明,Cu含量为20%~60%,随着Cu含量的提高耐磨性能先随之提高,Cu含量为40%时耐磨性能达到最优值,平均摩擦系数最小为0.172,磨损量为0.007 g;随着Cu含量的进一步提高耐磨性能反而降低。烧结温度为1096~1296℃时,随着烧结温度的提高耐磨性能随之提高,温度达到1196℃时耐磨性能达到最优,平均摩擦系数最小为0.123,磨损量为0.0018 g;烧结温度再提高耐磨性能反而降低。在最优工艺烧结过程中液相Al分别与Fe和Cu基体生成固溶体,使材料的密度和强度提高。MnS分解后,Mn与Fe基体生成固溶体,部分C也与Fe基体生成固溶体,两者促进了合金的固溶强化。其余的单质C,使合金的润滑性能提高。烧结后,Cu晶粒组织变得均匀细小,在Fe基中以网状形式存在。以上各组元的特殊作用使Fe-Cu基复合耐磨材料具有优异的耐磨性能。

The effect of Cu content and sintering temperature on the friction and wear properties of powder-metallurgical Fe-Cu based composites was investigated.The results show that the wear resistance first increases with the increase of Cu content within a range of 20%~60%Cu.Then the wear resistance reaches the optimum with the average friction coefficient of 0.172 and wear loss of 0.007 g for the composite with 40%Cu.However,the wear resistance begins to decrease when the Cu content further increases.Similarly,the wear resistance first increases with the increase of sintering temperature within the range of 1096~1296 oC.Then the wear resistance achieves the optimum with the average friction coefficient of 0.123 and wear loss of 0.0018 g for the composite sintered at 1196 oC.When sintering at higher temperatures,the wear resistance decreases again.During sintering with optimal process parameters,the molten Al may form solid solution with Fe and Cu,which improves the density and strength of the composite.Meanwhile,the decomposition of MnS yields atomic Mn,which mainly forms solid solution with Fe.Also,a part of C in the composite also forms solid solution with Fe.The above facts may in turn generate the solid solution strengthening of the Fe-Cu based alloy.Besides,there exists residual elemental carbon in the Fe-Cu based alloy,which enhances the lubrication of the alloy.After sintering,the grains of Cu become finer presenting as a network in the Fe based matrix.The excellent wear resistance of Fe-Cu based composite can be attributed to the special functions of the individual component of the composite.