过渡层厚度对TiN涂层结合性能的影响

Effect of Transition Layer Thickness on the Bonding Properties of TiN Coating

为了研究过渡层厚度对涂层结合性能的影响机理和规律,采用阴极弧离子镀技术在钛合金表面制备TiN涂层,以Ti作为过渡层,通过调整过渡层厚度来对比涂层的断裂韧性、显微硬度、断口形貌以及结合强度的变化规律。结果显示:TiN涂层均沿(111)密排面择优取向,涂层断口均呈现柱状晶结构。随着过渡层厚度的增加,涂层的断裂韧性先增加后减小,断口韧窝逐渐变大、加深,由沿晶断裂发展为穿晶断裂,结合强度先增加后降低,在过渡时间9 min时达到最高值62 N。沉积最佳厚度的Ti过渡层能够吸收变形能量、控制残余应力,能有效提高涂层的结合性能。

For studying the effect mechanism and regularity of the transition layer thickness on the bonding properties of coatings,TiN coatings were prepared on the surface of titanium alloy through cathodic arc ion plating technology using Ti as the transition layer.The change rules of fracture toughness,micro-hardness,fracture morphology and bonding strength of the coating were studied by adjusting the thickness of the transition layer.Results showed that all TiN coatings showed a preferred orientation along(111)close-packed surface,and the coating fractures presented a columnar crystal structure.As the thickness of the transition layer increased,the fracture toughness of the coating first increased and then decreased,and the fracture dimples gradually became larger and deeper,resulting in a change from inter-granular fracture to trans-granular fracture.Meanwhile,the bonding force of the coating increased first and then decreased,and reached the highest value of 62 N when the transition time was 9 minutes.In general,the Ti transition layer with the optimal thickness could absorb deformation energy,control residual stress,and improve the bonding properties of the coating effectively.