AlCrN/VN多层涂层力学性能及其热稳定性  

Mechanical Properties and Thermal Stability of AlCrN/VN Multilayer Coatings

作　　者：万强 罗畅 魏民 李晓峰 肖洋轶 王鹏 张俊[3] 杨兵[3] WAN Qiang;LUO Chang;WEI Min;LI Xiao-feng;XIAO Yang-yi;WANG Peng;ZHANG Jun;YANG Bing(School of Engineering, Huazhong Agricultural University, Wuhan 430070, China;Dating Boiler andPressure Vessel Inspection Center Co., Ltd, Hefei 230031, China;School of Power &Mechanical Engineering, Wuhan University, Wuhan 430072, China)

机构地区：[1]华中农业大学工学院,武汉430070 [2]大唐锅炉压力容器检验中心有限公司,合肥230031 [3]武汉大学动力与机械学院,武汉430072

出　　处：《表面技术》2019年第4期130-136,共7页Surface Technology

基　　金：国家自然科学基金(U1832127);中央高校基本业务经费(2662016QD045);湖北省自然科学基金(2018CFB227)~~

摘　　要：目的制备高硬度自润滑AlCrN/VN纳米多层复合涂层,提升刀具耐磨性,增加刀具寿命。方法采用多弧离子镀技术在单晶硅(100)、不锈钢以及硬质合金基底上沉积不同调制周期的Al Cr N/VN纳米多层涂层,系统研究涂层力学性能、滑动摩擦性能及高温稳定性。涂层制备采用Al_(70)Cr_(30)合金和单质V靶材,EDS结果显示涂层Al/Cr比例接近靶材成分,V元素原子比约为30%。利用扫描电镜(SEM)、原子力显微镜(AFM)以及X射线衍射技术(XRD)表征涂层显微结构,采用显微硬度仪以及滑动摩擦试验研究涂层硬度以及摩擦性能随调制周期的变化。最后对调制周期为24nm的涂层进行氧化实验,并测试其硬度与摩擦系数。结果沉积涂层厚度以及相组成几乎不受调制周期的影响。沉积涂层硬度与调制周期紧密关联,摩擦系数随着调制周期的减小而逐渐降低。当调制周期为24 nm时,涂层获得最大硬度,为3970HV_(0.05),此时涂层表面最为光滑(Ra=33.6 nm)。对调制周期为24 nm的多层涂层进行不同温度下空气氧化并测定其硬度与摩擦系数,结果表明硬度随着氧化温度升高到400、500、700℃而下降至1474、1248、370HV_(0.05),摩擦系数随之大幅度升高。结论 VN涂层的加入使得AlCrN涂层硬度降低,摩擦系数降低,且其硬度以及摩擦系数受到调制周期的显著影响,涂层经400℃氧化后,硬度值大幅度降低,热稳定性不好。The preparation of AlCrN/VN nano-multilayered coating with high hardness and self-lubricating properties aims to prolong the service life by improving the wear properties of cutting tools. AlCrN/VN nano multi-layer coatings with different bilayer thickness(deposited with different rpm) were deposited onto Si(100), stainless steel and cemented carbide substrates by cathodic arc ion-plating with Al70Cr30 and V targets to study the mechanical properties, sliding friction and high thermal stability. The Al:Cr atomic ratios of AlCrN coatings measured by EDS were closed to the ratio of Al70Cr30 target composition and V was about 30 at%. The microstructure of coatings was characterized by SEM, AFM, and XRD. The variation of hardness and friction properties along with the bilayer period was studied by micro-hardness test and sliding test. The oxidation test was carried out in samples with a bilayer thickness of 24 nm to investigate the hardness and friction coefficient. The compositions,thickness and phase structure were hardly affected by the bilayer thickness. The hardness was depended on the bilayer thickness and the friction coefficient decreased with increasing bilayer thickness. The maximum hardness 3970 HV0.05 was obtained when bilayer thickness was 24 nm. Meanwhile, the coating also showed the smoothest surface with roughness of 33.6 nm. After oxidation, the hardness of coating with a bilayer thickness of 24 nm decreased from 1474 to 1248, 370 HV0.05 as the temperature increased from 400 to 500, 700 ℃ and friction coefficient increased greatly. The addition of VN coating can reduce the hardness and friction coefficient of AlCrN coating which are affected obviously by the bilayer period. After oxidation at 400 ℃, the hardness of coating decreases dramatically, indicating the poor thermal stability.

关 键 词：AlCrN/VN 多弧离子镀 调制周期 显微结构 力学性能 热稳定性 

分 类 号：TG174.442[金属学及工艺—金属表面处理]