抄録
Cantilever type rotating bending fatigue tests were performed using A5052 aluminum alloy with hybrid coating of tungsten carbide including 12% cobalt (WC-12Co) interlayer and diamond-like carbon (DLC) film in order to investigate the effect of hybrid coating on the fatigue behavior. The WC-12Co layer was thermally sprayed by a high velocity oxygen fuel (HVOF) method on A5052 with the thickness of 70, 120 and 17011m. After that the DLC film was deposited with the thickness of 15[im. The fatigue strength of A5052 with WC-12Co single layer coating was improved compared with that of A5052 without coating and with the increase of thickness of WC-l2Co single layer, the fatigue strength was more improved. The fatigue strength of A5052 with the hybrid coating of 70tim WC-12Co and 15pm DLC film was more improved than that of A5052 with 70[tm WC-l2Co single layer coating and the hybrid coating was effective to improve the fatigue strength. However the effect of hybrid coating was not apparent in A5052 with thicker WC-l2Co layer of 120 and 170tim. Whether the hybrid coating is effective or not depends on that the DLC film could suppress the cracking of WC-12Co layer.
