Study on Improvements of Tribological Properties of Magnesium Alloys: Diamond-Like Carbon Film Coating with the Interface Layer of Carbonaceous Film Containing Silicon

摘要

We study about tribological surface modifications of magnesium alloys with diamond-like carbon (DLC) films, developing an interface layer between magnesium alloy and DLC film. In our previous works, carbonaceous thin films containing silicon (Si-DLC) as the interface layer have relatively low intrinsic stresses by adjusting deposition conditions. The Si-DLC films were prepared on the magnesium alloy substrates and the DLC films were continuously deposited by RF plasma CVD method with tetramethylsilane and iso-butane as starting materials, respectively. As a result, the Si-DLC/DLC layers films show satisfied adhesion to the magnesium alloy, and specific wear rates of the surface modified magnesium alloy with the two-layers films display an excellent resistance behavior for the alumina ball (～10{sup}(-7) mm{sup}3/Nm), in comparison with non-coated magnesium alloy (～10{sup}(-3) mm{sup}3/Nm). In this study we can achieve tribological surface improvements of magnesium alloys with sufficient adhesion and durability for practical uses.