CYCLIC DEFORMATION AND TRIBOLOGICAL BEHAVIOR OF AN AMORPHOUS IRON-BASED ALLOY FILM

To study the cyclic deformation and tribological behavior of amorphous alloy films and blocks (powder compacts), two types of fatigue test (cyclic bending) apparatus, wear rate test apparatus and an apparatus for measuring static and kinetic friction coefficients were constructed. From the strain amplitude-lifetime curves obtained, it was found that the fatigue limit of the amorphous films is higher than that of ordinary metal films such as 304 stainless steel films and that the fatigue limit obtained by testing three types of amorphous films, i.e. iron-based, cobalt-based and nickel-based ones, in dry argon gas and in vacuum is even higher than that obtained by testing in air. The wear rate of amorphous iron-based alloy films is much less than that of crystalline specimens tested, and the wear volume tends to saturate above a certain sliding speed of the disc. As regards the static and kinetic friction coefficients of the amorphous specimens (mu-s and mu-k, respectively), both are lower than those of crystalline specimens, in particular, in the case of mu-k for amorphous-amorphous contact (mu-k = 0.04).