Research On The Synthesis Of New Aluminum-zinc Bearing Alloy

Aluminum alloy has a lot of advantages, such as excellent thermal conductivity, highcorrosion resistance, richness in resources, and low price et al. Aluminum alloy graduallybecome the primary choice for mechanical parts. Al-Zn alloy with good resistance to wear,the matrix of Al-Zn has good comprehensive mechanical properties, and the phase of CuAl2in the matrix has high hardness. The hard phase is distributed in a soft base alloy.So thismaterial is a typical bearing material.Bearing materials which have been using currently contained lead et al. Lead is not onlydetrimental to environmental, but also harmful to human body. And tin is a scarce element onthe earth, if tin was used in bearing materials, it will lead to high cost of production. Thisstudy fabricate a new Al-Zn alloy bearing material. This material has a high performance andlower price, meantime it is not harmful to the environment.In order to solve the influence of Al-Zn alloy with high hardness applied on theperformance of bearing materials, increase the bearing rate of the materials, and improve thelubrication of sliding bearing, this study adopted powder metallurgy method to preparebearing alloy. The Zn and Al powders were mixed by mechanical milling, and the Highzinc-aluminium alloy bulk was made by pressing and sequent vacuum sintering in thismethod. This paper mainly studies the effect of content of Zn, pressing pressure and sinteringtemperature on the performance of bearing materials by the microstructure observation,Brinell hardness test and detection of the wear.The results show that: the pristine powders were weighted and mixed well according tothe mass fraction:70.5%Al,25%Zn,3%Cu,1%Mg, and0.5%Si.200MPa pressure isapplied on the mixed powder. Then specimens were sintered at410℃under vacuum in avacuum sintering furnace. After that, Brinell hardness of samples prepared was measured andreached47.5. In addition, the abrasion loss was only was0.0503g when the sample wassubjected to wearing test for360min under positive pressure of30Kg with M2000-typewearing machine. At last overall performance was proved to be excellent. And observed bySEM, the phase of CuAl2is evenly distributed in the aluminum matrix. It also meet the designrequirements of the distribution of hard points on soft substrate。...