Abstract
In order to investigate the effect of coating condition on the fatigue properties of high strength steel, the four point bending fatigue tests were carried out for martensitic stainless steel with TiN film coated by arc ion plating (AIP) method. TiN film having 2μm thick was deposited onto the substrate surface under four kind of the bias voltage; V_B=0, -60, -160 and -260V. For V_B=0, -160V and -260V, the fatigue limit increased. The highest fatigue limit of σ_<max>=900MPa was obtained for V_B=-160V. For V_B=-60V and -260V with film delamination, the fatigue limit was decreased by coating. It appears that the fatigue properties of the coatings strongly depend on the crack initiation behavior. The fatigue crack initiated from subsurface in the substrate independent of bias voltages and the crack initiation life depended on the surface roughness, adhesive strength, residual stress, elastic modulus, and hardness of the films.
