Si含量对TiAlSiN纳米复合涂层的微观结构和力学性能的影响

Influence of Si Content on Microstructure and Mechanical Properties of TiAlSiN Nanocomposite Coatings

采用不同Si含量的TiAlSi复合靶,在Si基底片上用射频磁控溅射工艺沉积了TiAlSiN纳米复合涂层,采用X射线衍射仪(XRD)、高分辨透射电子显微镜(HRTEM)和纳米压痕技术研究了Si含量对TiAlSiN涂层的微观结构和力学性能的影响.结果表明:TiAlSiN涂层内部形成了Si3N4界面相包裹TiAlN纳米等轴晶粒的纳米复合结构.随着Si含量的增加,TiAlSiN涂层的结晶程度先增加后降低,涂层内部的晶粒尺寸先减小后趋于平稳,涂层的力学性能先升高后降低.当Si与TiAl原子比为3∶22时获得的最高硬度和弹性模量分别为37.1GPa和357.3 GPa.

Using TiA1Si targets with different Si contents,TiA1SiN nanocomposite coatings were deposited in Si substrate by R.F. magnetron sputtering. By means of X-ray diffraction （XRD）, high resolution transmission electron microscopy （HRTEM） and nano-indentation techniques,the influences of Si content on microstructure and mechanical properties of TiA1SiN nanocomposite coatingswere investigated. The results show that the nanocomposite structure with TiA1N nanocrystallites surrounded by Si3N4 interracial phase formed within the TiA1SiN coating. With the increase of Si content, the crystallization degree of TiA1SiN coating first increased and then decreased, grain size of the coatings firstdecreased and then kept stable, the mechanical properties of the coatings first improvedand then reduced. When the ratio of Si （atom%） and TiA1 （atom%） constituents was 3：22, the maximum hardness and elastic modulus could respectively reach 37.1 GPa and 357.3 GPa.