磁控溅射ZrAlN薄膜的硬度和断裂韧性

Hardness and Toughness of Magnetron Sputtering ZrAlN Films

采用磁控溅射技术在钛合金和单晶Si上沉积原子分数x(Al)分别为5%、23%、47%、63%的ZrAlN薄膜,并考察了薄膜硬度和断裂韧性。采用场发射扫描电镜观察截面形貌,X射线衍射(X-Ray Diffraction,XRD)分析物相结构。采用纳米压入仪进行10 mN加载、卸载试验,分析了薄膜的弹塑性变形特性;采用压入法定量比较了薄膜的断裂韧性。试验发现:原子分数x(Al)分别为5%、23%、47%、63%的ZrAlN薄膜对应硬度分别为24.5、40.1、17.1、19.1 GPa;对应断裂韧性分别为1.47、3.17、1.13、1.58 MPa·m1/2;x(Al)=23%的薄膜保持了ZrN的金属键特性,韧性最好;而x(Al)=47%的薄膜表现强烈离子键特性,韧性最差。XRD表明:x(Al)分别为5%和23%时,Al原子固溶到ZrN晶粒中,保持ZrN立方结构;而x(Al)分别为47%和63%时,形成纤锌矿AlN第二相。

ZrAlN films containing variable amounts of aluminum,namely x( Al) = 5%,23%,47%, 63%,are deposited onto TC6 and Si wafers by magnetron sputtering method in an argon / nitrogen gas mixture,and hardness and toughness of films are investigated. The morphology of coatings is investigated by Field Emission Scanning Electron Microscopy( FESEM),the microstructure is studied by X-Ray Diffraction( XRD). The plastic deformation characteristics of thin films are analyzed from 10 mN loading / unloading test by nano-indenter. The fracture toughness of films is determined from the length of radial cracks on the applied diamond indenter load 1. 96 N. The experiment discovers: x( Al) = 5%,23%, 47%,63% ZrAlN films possess corresponding hardness values of 24. 5,40. 1,17. 1,19. 1GPa,corresponding fracture toughness values of 1. 47,3. 17,1. 13,1. 58 MPa·m0. 5,respectively,thus x( Al) = 23%,thin film maintains ZrN metallic bond characteristics,and possesses the best toughness,but x( Al) =47% film displays intense ionic bond characteristic and poorest toughness. XRD indicates that x( Al) =5%,23%,Al dissolves within ZrN grains,whereas x( Al) =47%,63%,Al forms wurtzite AlN second phase.