物理气相沉积CrN和AlCrN薄膜的摩擦学性能

发布时间：2018-02-14 17:19

  本文关键词： 物理气相沉积 CrN薄膜 AlCrN薄膜 摩擦学性能　出处：《中国地质大学(北京)》2017年硕士论文　论文类型：学位论文

【摘要】：物理气相沉积是改善机械零部件表面摩擦学性能的重要表面工程技术。本文针对切削刀具的高温磨损问题采用阴极电弧离子镀法制备了CrN和AlCrN薄膜,然后对CrN和AlCrN薄膜进行常温摩擦磨损试验,并分别在大气和真空环境中对AlCrN薄膜进行热处理。采用磁控溅射法制备了4种不同参数的AlCrN薄膜,在大气环境中对其进行热处理。选择参数:Ar气流量100 sccm的样品进行高温摩擦磨损试验。利用三维白光形貌仪、扫描电子显微镜、纳米压痕仪和摩擦磨损实验仪等分析测试仪器测试分析了薄膜的表面形貌、组织结构、硬度和相组成。探讨氮化物薄膜常温和高温摩擦学性能及机理。结果如下:(1)阴极电弧离子镀制备的CrN薄膜表面平整,缺陷较少,其纳米硬度和弹性模量分别为28 GPa和350 GPa。对磨球为Si3N4陶瓷球时,CrN薄膜的磨损机制主要为磨粒磨损,伴有少量的氧化和粘着磨损,316L不锈钢的磨损机制主要为磨粒磨损和塑形变形,伴有少量的氧化和粘着磨损。对磨球为52100钢球时,CrN薄膜的主要磨损机制为粘着磨损,伴有少量的氧化,316L不锈钢的磨损机制主要为粘着磨损,伴有少量的氧化和磨粒磨损。(2)阴极电弧离子镀制备的AlCrN薄膜表面平整,由CrN、AlCrN和AlN三种相组成,薄膜纳米硬度为18 GPa,弹性模量为290 GPa。干摩擦条件下,AlCrN薄膜具有良好的承载能力,磨损机制主要为磨粒磨损。在PAO4润滑油条件下,其磨损率随载荷的增大而增大,其磨损机制主要为粘着磨损,并有轻微的磨粒磨损。大气环境下,AlCrN薄膜在800℃时开始出现氧化相Cr2O3,并且在800℃下仍能保持较高的纳米硬度和弹性模量,分别为15 GPa和260 GPa。(3)磁控溅射法制备的4种参数的AlCrN薄膜表面没有明显差别,整体平整致密,薄膜表面有CrN、AlCrN、AlN三种氮化物相,Al元素和Cr元素的氧化产物Al2O3和Cr2O3有效提高了薄膜的抗氧化性和力学性能。Ar/N2气体流量为100s ccm/50 sccm的AlCrN薄膜与SiC球对磨时,高温条件下的摩擦系数均高于20℃时的摩擦系数。20℃条件下AlCrN薄膜的磨损机制主要是磨粒磨损,同时有粘着磨损和氧化磨损,高温条件下,AlCrN薄膜的磨损机制是塑性变形、磨粒磨损、氧化磨损和粘着磨损的复合磨损。
[Abstract]:Physical vapor deposition is an important surface engineering technology to improve the tribological properties of mechanical parts. In this paper, CrN and AlCrN thin films were prepared by cathode arc ion plating for cutting tool wear at high temperature. Then the CrN and AlCrN thin films were tested by friction and wear at room temperature, and the AlCrN films were heat-treated in atmosphere and vacuum respectively. Four kinds of AlCrN thin films with different parameters were prepared by magnetron sputtering. The heat treatment was carried out in atmospheric environment. The friction and wear tests were carried out at high temperature by selecting the sample with the flow rate of 1: ar gas for 100 sccm. The three dimensional white light profilometer, scanning electron microscope, scanning electron microscope (SEM) were used. Nano-indentation instrument and friction and wear tester etc., the surface morphology, microstructure and structure of the film were tested and analyzed. Hardness and phase composition. Tribological properties and mechanism of nitride films at room and high temperatures are discussed. The results are as follows: the surface of CrN films prepared by cathodic arc ion plating is flat and the defects are less. The wear mechanism of CrN film is mainly abrasive wear when the grinding ball is Si3N4 ceramic ball, and the wear mechanism of 316L stainless steel with a small amount of oxidation and adhesive wear is mainly abrasive wear and plastic deformation. The main wear mechanism of CrN film is adhesive wear when the grinding ball is 52100 steel ball, and the adhesive wear is the main wear mechanism of stainless steel with a small amount of oxidized 316L stainless steel. The surface of AlCrN film prepared by cathodic arc ion plating with a small amount of oxidation and abrasive wear is smooth, which consists of three phases: CrNO AlCrN and AlN. The nano-hardness of the film is 18 GPaand the elastic modulus is 290GPa. the thin film has good bearing capacity under dry friction condition. The wear mechanism is mainly abrasive wear. Under the condition of PAO4 lubricating oil, the wear rate increases with the increase of load, and the wear mechanism is mainly adhesive wear. At 800 鈩，

本文编号：1511208