粉末靶脉冲磁控溅射制备CrBMoS固体润滑硬质涂层

Synthesis and Tribological Properties of Composite CrBMoS Coatings by Pulsed Magnetron Sputtering of Powders

粉末靶封闭非平衡磁场脉冲磁控溅射是一种方便靶材配比、节约靶材成本的高效磁控溅射工艺,其特点是将固体粉末按成分需求配比,直接作为磁控靶体。CrB_2则因其高硬度而常被作为硬质耐磨材料使用,MoS_2因其低摩擦系数常作为固体润滑剂使用。本研究则将CrB_2和MoS_2两种粉末按Cr∶Mo原子比1∶1混合,利用粉末靶封闭非平衡磁场脉冲磁控溅射系统在304不锈钢表面制备硬质固体润滑涂层,探讨脉冲频率对CrBMoS涂层结构及性能的影响。用示波器测量靶电位曲线,分别用扫描电子显微镜、X射线衍射分析涂层形貌及相结构,表面形貌轮廓仪测量涂层厚,纳米压痕仪检测涂层纳米硬度,划痕仪测量涂层结合力及摩擦磨损实验机测量涂层摩擦系数。结果表明,在脉冲"开-关"状态转换时,靶电位由"负"转"正"过程中,"正"电位突升。随脉冲频率增高,涂层的沉积速率降低,沉积速率与有效沉积时间因子成正比。涂层致密、无缺陷,涂层晶体择优取向分别为CrB_2(111)及MoS_2(200)。涂层纳米硬度最高可达19 GPa,摩擦系数最小低至0.02。结果表明粉末靶封闭非平衡脉冲磁控溅射法制备的CrBMoS涂层具有较高硬度的同时,还具有良好的固体润滑效果。

The CrBMoS composite coatings were deposited by pulsed closed field unbalanced magnetron sputtering of the mixed CrB2 and MoS2 powders（ Cr∶ Mo = 1∶ 1 at. %） on substrate of 304 stainless steel. The influence of the frequency and ＂pulse-fact＂（ defined as the product of width and duty-cycle and describing effective deposition time） of target voltage on the microstructures,phases and tribological behavior of the coatings was investigated with X-ray diffraction,scanning electron microscopy and conventional mechanical probes. The preliminary results show that the frequency and pulse-factor have a major impact. For instance,the deposition rate increased with an increase of pulse-factor but decreased with an increase of frequency. Grown under the optimized conditions,the compact uniform columnar CrBMoS coatings with fairly strong interfacial adhesion,comprising CrB2111 and MoS2200 preferentially-grown grains,displayexcellent tribological properties,including the highest nano-hardness of 19 GPa and the lowest friction coefficient of 0. 02.