沉积气氛中CO对MT-Ti(C,N)的微观结构及应用性能的影响

Effect of CO in Deposition Gas on Microstructure and Application Performance of MT-Ti(C,N)

CVD涂层技术是一种被广泛应用于硬质合金可转位刀具的表面处理技术,TiN/MT-Ti(C,N)/α-Al_(2)O_(3)/TiN是目前主流的CVD(Chemical Vapor Deposition)多功能复合涂层,在CVD沉积气氛中添加CO是实现MT-Ti(C,N)的涂层结构、性能调控较为简洁的工业化方式。本文在CVD涂层沉积气氛中添加CO,制备了单层MT-Ti(C,N)及典型的MT-Ti(C,N)/α-Al_(2)O_(3)双层结构涂层,研究了CO添加量对其微观组织、力学性能、涂层结合力及切削性能的影响。结果表明,CO的添加不会改变Ti(C,N)的晶体结构,但会改变Ti(C,N)的晶粒取向,并随着CO添加量的提升逐步细化Ti(C,N)晶粒。CO添加量的变化会引起α-Al_(2)O_(3)取向的变化和涂层结合力的变化,当添加体积分数1%和2.5%的CO时,涂层的常温结合力较好,连续切削寿命较高。

CVD coating is a surface treatment technology widely used in cemented carbide indexable inserts.TiN/MTTi(C,N)/α-Al_(2)O_(3)/TiN is one of the mainstream CVD multifunctional composite coating.The addition of CO in CVD deposition gas is a simple industrial way to control the structure and properties of MT-Ti(C,N) coating.In this research,single-layer MTTi(C,N) and typical two-layer MT-Ti(C,N)/α-Al_(2)O_(3) coatings were prepared by adding CO in CVD deposition gas,and the effect of CO addition on the microstructure,mechanical properties,adhesion and cutting performance of the coatings were investigated.The results show that the addition of CO do not change the crystal structure of Ti(C,N) but changes the grain orientation of Ti(C,N),while Ti(C,N) grains are gradually refined with the increasing of the CO amount.In addition,changes in the CO amount results in the changes of the α-Al_(2)O_(3) orientation and coating adhesion.When the volume fraction of CO is 1% and 2.5%,the coating exhibits good room-temperature adhesion and long continuous cutting tool life.