用等离子喷涂强化零件表面和修复零件时,预热是必要的。预热可以减少粉末颗粒与零件喷涂表面的温差,降低涂层产生的残余应力。但预热温度和保温时间不同,又会使零件生成不同性质和不同厚度的氧化膜,从而影响涂层与基件的结合强度。预热温度和保温时间与零件的尺寸、形状、传热系数及线膨胀系数有关。本文研究了45号钢试件喷涂复合粉镍包铝时,预热温度、保温时间对涂层结合强度的影响。 Preheating is necessary when using plasma spraying to reinforce part surfaces and repair parts. Preheating can reduce the temperature difference between the powder particles and the sprayed surface of the part and reduce the residual stress generated by the coating. But the preheating temperature and holding time are different, will make the parts generate different nature and different thickness of the oxide film, thus affecting the coating and the base of the bonding strength. Preheat temperature and holding time and the part size, shape, heat transfer coefficient and linear expansion coefficient. In this paper, the effect of preheating temperature and holding time on the bonding strength of 45 # steel was investigated.