调制比对Cr/CrN/Cr/CrAlN多层膜结构及性能的影响

目的 探究Cr/CrN/Cr/CrAlN多层膜的最佳调制比.方法 利用电弧离子镀技术,在TC4钛合金上制备了不同调制比的Cr/CrN/Cr/CrAlN多层膜.利用扫描电子显微镜观察膜层表面和截面形貌;用Image-Pro分析软件对表面的大颗粒进行定量分析;利用X射线衍射法表征膜层的晶体结构;采用维氏硬度计测量膜层的显微硬度;采用划痕试验仪测量膜层与基体之间的结合力(临界载荷);通过基片弯曲法测量并计算得到膜层的残余应力;利用根据ASTM G76-05标准特制的AS600-喷砂试验机进行了抗冲蚀性能测试;采用三维表面轮廓仪测量冲蚀坑深度.结果 膜层表面质量和生长取向与LCr/CrN:LCr/CrAlN调制比密切相关,随着Cr/CrN比例的增加,膜层表面质量越来越好,择优取向由(111)晶面转为(200)晶面.多层膜的硬度随Cr/CrN比例的增加,呈下降趋势,结合力、残余应力和韧性则随之呈先升后降的趋势,并在LCr/CrN:LCr/CrAlN为1:2时,达到最佳.多层膜的抗砂粒冲蚀性能变化与力学性能变化一致,在LCr/CrN:LCr/CrAlN为1:2时达到最佳,其抗冲蚀能力是TC4基材的3倍以上,多层膜呈典型的脆性断裂失效形式.结论 在调制比LCr/CrN:LCr/CrAlN=1:2时,膜层获得最佳的抗冲蚀性能.

Effects of Modulation Ratios on the Structures and Properties of Cr/CrN/Cr/CrAlN Multilayer

In order to study the effect of modulation ratio on the structure and properties of Cr/CrN/Cr/CrAlN multilayers. Cr/CrN/Cr/CrAlN multilayers with different modulation ratios were prepared on TC4 titanium alloy by arc ion plating. Scanning electron microscope (SEM) was used to observe the surface and section morphologies of the film, and Image-Pro software was used to quantitatively analyze the large particles on the surface. The crystal structure of the film was characterized by X-ray diffraction. The microhardness of the film was measured by Vickers hardness tester, and the binding force (critical load) between the film and matrix was measured by scratch tester. The residual stress of the film was measured and calculated by the substrate bending method. According to ASTM G76-05 standard, AS600-sandblasting tester was used to test the anti-erosion performance. The depth of offset pits was measured by 3D surface profilometer. The results showed that LCr/CrN:LCr/CrAlN modulation ratio was closely correlated with the surface quality of the films. With the increase of Cr/CrN ratio, the surface quality of the films became better and the preferred orientation changed from (111) plane to (200) plane. The hardness of multilayer films decreased with the increase of Cr/CrN ratio, while the bonding force, residual stress and toughness increased first and then decreased, and reached the best when the ratio of LCr/CrN:LCr/CrAlN was 1:2. The sand erosion resistance of multilayer film was also consistent with the main mechanical properties, and it was the best when LCr/CrN:LCr/CrAlN was 1:2. The erosion resistance of multilayer film was 3 times higher than that of TC4 substrate. The fracture surface of the multilayer film revealed a typically brittle feature. When the modulation ratio LCr/CrN:LCr/CrAlN=1:2, the film has the best anti-erosion performance.