磁控溅射TiAlNO薄膜的结构与力学性能

Structure and mechanical properties of TiAlNO thin films prepared by RF reactive magnetron sputtering

采用独立的Ti靶和Al靶,用射频反应磁控溅射方法,逐步控制氧流量在高速钢(W18Cr4V)基体上沉积了一系列具有不同氧含量的TiAlNO薄膜。研究了氧流量对薄膜组织结构、硬度和摩擦性能的影响。结果表明,在(Ti,Al)N中加入氧形成由(Ti,Al)(N,O)纳米晶和(TiO2,Al2O3)非晶组成的复合结构。随着氧流量的增加,薄膜中晶体相晶格常数逐步减小,其取向则逐步从(111)为主转变为(111)和(200)混合。同时薄膜硬度缓慢地下降,摩擦系数和磨损量先减少后增大,在氧流量为0.9 sccm时达到最小值。研究同时表明,当氧流量为0.9 sccm时薄膜具有最小摩擦系数和高耐磨性,同时保持了高硬度,综合性能最好。

A series of TiAlNO thin films with different oxygen contents were deposited on high-speed （W18Cr4V） steel by RF reactive magnetron sputtering process using separate Ti and Al targets. The effects of oxygen flow rate on microstructure, microhardness, friction coefficient and wear rate were subsequently studied. The results indicated that the incorporation of （Ti, Al）N is prone to form nc-（Ti,Al）（N,O）/a-（TiO2,Al2O3） structure. With increase of oxygen flow rate the lattice parameter of nanocrystallites in thin films gradually decreases, while its preferred orientation transformes from dominant （111） to mixed （111） and （200）. Simultaneously the film hardness gradually decreases. Both friction coefficient and wear rate decreases with oxygen flow rate, and their minimums are obtained at an oxygen flow rate 0.9sccm. An increase in both values is followed with further increase of oxygen flow rate. The thin films deposited at an oxygen flow rate of 0.9sccm possesse the best mechanical properties with minimum friction coefficient and high to wear-off hardness.