VN基硬质耐磨涂层的制备及其性能

目的在N2及其与C2H2混合气氛下,制备VN基硬质耐磨涂层,研究VN基涂层的结构及力学、耐磨、抗腐蚀性能,为工业化应用积累科学数据。方法采用阳极层离子源辅助阴极电弧离子镀系统,在高速钢衬底上制备VN、VCN和VCN/VN多层涂层,系统研究多层涂层调制周期厚度变化对涂层晶体结构、表面形貌、硬度、耐磨性及耐腐蚀性能的影响。结果 C原子的加入和VCN/VN多层涂层调制周期的变化对VCN/VN涂层的晶体结构、表面形貌、硬度、摩擦系数及耐腐蚀性能均有明显影响。随着VCN/VN涂层调制周期的增加,VN(200)衍射峰逐渐减弱并宽化,VN (111)衍射峰消失,涂层表面金属熔滴大颗粒数量减少,小颗粒数量明显增加。VN涂层硬度为1890HV,VCN涂层硬度为2290HV,VN/VCN多层涂层硬度为2350HV左右。对磨材料为氧化铝时,VN涂层的摩擦系数为0.74左右,VCN涂层和VCN/VN涂层的摩擦系数明显降低,在0.60左右,磨损机理由以磨削磨损为主(VN涂层)逐渐转化为粘着磨损为主(S5),磨削磨损起次要作用。随着C原子的加入和VCN/VN多层涂层调制周期的变化,涂层耐腐蚀性能明显增强,自腐蚀电位由VN的-0.26 V增大到VCN的-0.14 V,自腐蚀电流密度由1.63′10^-5 A/cm^2降低到2.7′10(-6) A/cm^2。结论采用阳极层离子源辅助电弧离子镀技术可制备VN基硬质耐磨涂层,C元素的加入可有效提高VN涂层的硬度,降低VN涂层的摩擦系数,增强VN涂层的耐腐蚀性能。VCN/VN多层涂层通过周期厚度的调制可以有效提高VN基涂层的硬度、耐磨及耐腐蚀性能。

Preparation and Properties of VN Based Antiwear Hard Coatings

The work aims to deposit VN based hard coatings under the gas mixture of N2 and C2H2 to investigate microstructure and mechanical, tribological and corrosion properties and provide scientific data for industrial application. VN, VCN and VCN/VN multi-layer coatings were deposited on high speed steel substrates by cathodic arc ion plating assisted by an anode layer ion source to study the effects of the modulation period on microstructure and mechanical, tribological and corrosion properties of multi-layer coatings. The addition of C atom and variation of the modulation period both had obvious influence on the crystal structure, surface morphology, hardness, friction coefficient and corrosion resistance of VCN/VN coatings. With the increase of the modulation period of VCN/VN, the diffraction peak of VN(200) was gradually weakened and broadened, and the diffraction peaks of VN(111) disappeared. The number of the large size particles on the coating surface decreased while the number of the small size particles increased. The microhardness of VN coatings, VCN coatings and VN/VCN multi-layer coating was 1890 HV, 2290 HV and 2350 HV. For alumina ball, the friction coefficient of VN coating was about 0.74, and the friction coefficients of VCN coating and VCN/VN coatings obviously decreased, about 0.60. The wear mechanism was mainly grinding wear(VN coating) and gradually transformed to adhesive wear(S5) and the grinding wear played the minor role. With addition of C atom and variation of the modulation period of VCN/VN multi-layer coating, the corrosion resistance of coating obviously increased and the corrosion potential increased from-0.26 V of VN to-0.14 V of VCN while the corrosion current density decreased from 1.63′10-5 A/cm2 to 2.7′10-5 A/cm2. Cathodic arc ion plating assisted by an anode layer ion source can be used to deposit VN based hard coating. The addition of C atom can effectively increase the hardness of VN coating and reduce the friction coefficient, thus strengthening the corrosion resistance. The thickness modulation of VCN/VN multi-layer coating can effectively improve the hardness and wear and corrosion resistance of VN based coating.