High Cycle Fatigue Damage of HVAF WC-10Co4Cr Coating

The high cycle fatigue (HCF) properties of chrome plating and WC-10Co4Cr coating prepared by HVAF (high velocity air fuel) on 300M steel were tested.The crack and delamination mechanism of the coatings after HCF were analyzed by means of SEM and EDS.The results indicate that many parallel cracks,perpendicular to the loading direction,were found on WC-10Co4Cr coating after 2/3 HCF life,indicating normal fracture.Delamination of WC-10Co4Cr coating was observed near to the fracture surface after fatigue fracture,and with the increase of load,the delamination area increased.No obvious crack was found on chrome plating after fracture.There was a little delamination of the coating under high load.