利用纳米颗粒特殊的热学性能和力学性能,在制造粉末冶金齿轮的原料铁粉(微米级)中添加1%和3%(质量分数)的纳米铁粉,先后进行混料、压制和渗碳烧结等制造工序,然后将得到的齿轮进行硬度、密度、显微组织和断口形貌等测试分析。试验结果表明,添加纳米粉末的样品可以将烧结和渗碳两个工艺过程在920 ℃加热时同时完成,并且样品的硬度和密度均有一定程度的提高。

The nanometer material has many special properties such as surface effect,stability and small dimension effect that different from other materials. It can decrease the sintering temperature and the number of the hole of iron basic powder metallurgy parts. Using these special calorifics and mechanics properties,add 1% and 3% in mass percent nanometer iron powder into the raw iron powder (micron class) of producing powder metallurgy gear wheel′s,and carry through different manufacturing processes such as mixing the materials,pressing and carbonizing sintering,then carry out analysis for the test of hardness,density,microstructure of the samples. The result shows that all the samples can be sintered successfully at 920 ℃ for carbonizing technique and present study shows that the hardness and density can be improved.