B和Si掺杂对CrAlN涂层结构和切削钛合金寿命的影响  

Effects of B and Si Doping on CrAlN Coating Structure and Tool Life of Cutting Titanium Alloy

作　　者：王羽中 史耀耀[1] 张国飞 贺云鹏 WANG Yu-zhong;SHI Yao-yao;ZHANG Guo-fei;HE Yun-peng(School of Mechanical and Electrical Engineering,Northwestern Polytechnical University,Xi'an 710072,China;Zhuzhou Cemented Carbide Cutting Tools Co.,Ltd.,Hunan Zhuzhou 412007,China)

机构地区：[1]西北工业大学机电学院,西安710072 [2]株洲钻石切削刀具股份有限公司研发中心,湖南株洲412007

出　　处：《表面技术》2023年第10期360-366,393,共8页Surface Technology

基　　金：国家科技重大专项(2017-Ⅶ-0002-0095)。

摘　　要：目的 CrAlN涂层以其优异的抗氧化性能被广泛应用于切削刀具涂层领域,针对CrAlN涂层热稳定性较低,在超过900℃后会发生热分解,导致其力学性能显著下降的问题,通过B、Si共掺杂方法改善CrAlN涂层的性能。方法 采用阴极弧蒸发方法制备Cr_(0.42)A1_(0.58)N、Cr_(0.35)Al_(0.59)B_(0.06)N、Cr_(0.37)Al_(0.54) Si_(0.09)N涂层,借助X射线衍射仪(XRD)、扫描电子显微镜(SEM)、纳米压痕仪,通过划痕和切削实验研究B和Si掺杂对CrAlN涂层晶体结构、硬度、结合力、热性能和切削寿命的影响。结果 Cr_(0.42)A1_(0.58)N和Cr_(0.35)A1_(0.59)B_(0.06)N涂层为单相立方结构,Cr_(0.37)Al_(0.54)Si_(0.09)N涂层为立方和六方的两相结构;Cr_(0.42)A1_(0.58)N、Cr_(0.35)Al_(0.59)B_(0.06)N、Cr_(0.37)A1_(0.54)Si_(0.09)N涂层的硬度分别为(29.8±1.5)、(36.9±1.4)、(33.8±1.6)GPa,与基体的结合力分别为116.2、58.3、58.0 N;通过B和Si掺杂抑制了CrAlN涂层的热分解过程,Cr-N键的断裂起始温度由Cr_(0.42)A1_(0.58)N的1 000℃提高到Cr_(0.35)Al_(0.59)B_(0.06)N的1 200℃和Cr_(0.37)Al_(0.54)Si_(0.09)N的1 100℃;在1 100℃下氧化15 h后,Cr_(0.42)A1_(0.58)N、Cr_(0.35)Al_(0.59)B_(0.06)N、Cr_(0.37)Al_(0.54)Si_(0.09)N涂层的氧化层厚度分别为2.38、1.80、0.53μm。结论 通过B和Si掺杂提高了CrAlN涂层的力学性能、热稳定性和抗氧化性,其中CrAlBN涂层呈现出最优异的热稳定性和切削性能,CrAlSiN涂层的抗氧化性最佳。Because CrAlN coating has excellent oxidation resistance components,it is widely used in the field of cutting tool coating.However,the thermal decomposition of CrAlN coating above 900℃ leads to a drop in mechanical properties.Therefore,B and Si doping method was adopted in this study to further improve the performance of CrAlN coating.The structure,hardness,cohesion,thermal and machining properties of Cr_(0.)4_(2)A1_(0.58)N,Cr_(0.35)Al_(0.59)B_(0.06)N and Cr_(0.37)Al_(0.54)Si_(0.09)N deposited by cathodic arc evaporation were investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM),nano-indentation,scratch test and cutting experiment.The Cr_(0.42)Al_(0.58)N and Cr_(0.37)Al_(0.54)Si_(0.09)N coatings presented a single phase cubic structure,whereas the Cr_(0.35)Al_(0.59)B_(0.06)N coating was mixed cubic-wurtzite structure.Cr_(0.42)Al_(0.58)N coating presented typical columnar crystal morphology along the growth direction.The addition of B and Si inhibited the growth of columnar crystals.The fracture morphology of Cr_(0.35)Al_(0.59)B_(0.06)N coating and Cr_(0.37)Al_(0.54)Si_(0.09)N coating was composed of fine columnar crystals and nanocrystals respectively.The solid solution strengthening and grain refinement caused by B and Si doping increased the hardness of the coating from(29.8±1.5)GPa of Cr_(0.42)A1_(0.58)N coating to(36.9±1.4)GPa of Cr_(0.35)Ak_(0.59B0.06)N coating and(33.8±1.6)GPa of Cr_(0.37)A1_(0.54)Si_(0.09)N coating.However,B and Si doping reduced the cohesion with substrate from 116.2 N of Cr_(0.42)Al_(0.58)N coating to 58.3 N and 58.0 N of Cr_(0.35)Al_(0.59)B_(0.06)N and Cr_(0.37)Al_(0.54)Si_(0.09)N.The grain refinement caused by the addition of B and Si reduced the elastic modulus of the coating.The elastic modulus of Cr_(0.42)Al_(0.58)N,Cr_(0.35)Al_(0.59)B_(0.06)N and Cr_(0.37)Al_(0.54)Si_(0.09)N coatings was 523.6,484.8 and 431.7 GPa respectively.The addition of B and Si improved the plastic deformation resistance of the coating.The ratios of H~3/E~2 of Cr_(0.42)Al_(0.58)N,Cr_(0

关 键 词：Cr_(1–x)Al_(x)N涂层 多元掺杂 热稳定性 抗氧化性 切削性能 

分 类 号：TG113.12[金属学及工艺—物理冶金]