Abstract: Plasma spraying process experiments on different subsracts,in cluding TC4 titanium alloy,45 steel,6061 aluminium alloy and fine copper,were conducted at same process parameters.The interface morphology between coats and substrate was observed under metallographic microscope and scanning electron microscope.The bonding strength between coats and substracte was also detected.The effects of the substract character on the residual stress,the interface bonding state and bonding strength of coating were also analysed.The results manifested that the physical paremeters of the substract,such as coefficient of thermal expansion,thermal conductivity,specific heat capacity,have a direct effect upon the residual stress and interface bonding state of coating,which then influences the bonding strength between coating and substrats.Establishing proper spraying procedure corresponding to different substract is a key approach to improve the bonding strength between coating and substract.