Abstract:
The surfaces of 2219 Al-alloy,an advanced material in lightweight design of structural parts in automotive and aircraft industries,were modified with the Al
2O
3-doped Ni-coatings deposited by plasma spraying of Ni and Al
2O
3 micron powders.The influence of the Al
2O
3-content on the microstructure and tribological behavior of the coating was experimentally studied with X-ray diffraction,scanning electron and conventional mechanical tools The results show that the Al
2O
3-doping had a major impact.Specifically,the Al
2O
3-doping significantly increased the hardness up to 3 times higher than that of the substrate at most; as the Al
2O
3-content increased from 15% to 40%,the hardness increased,accompanied by the decreases of both the wear-rate and friction coefficient,possibly because the “black-spot” area,mainly comprising Al and Al
2O
3,considerably increased.In addition,the oxidative wear was found to be responsible for the wear mechanism.