恒电位对TiN涂层在人工海水环境中腐蚀磨损的影响

目的研究不同恒电位对TiN涂层在人工海水环境中腐蚀磨损行为的影响。方法用多弧离子镀系统在316不锈钢上沉积TiN涂层。通过XRD测试、纳米压痕硬度测试、膜基结合力测试、电化学工作站测试、不同恒电位下磨蚀实验和涂层的磨痕截面轮廓测试,分别评价TiN涂层的相结构、硬度、结合力、电化学性能、摩擦系数、磨损率,并通过扫描电子显微镜对涂层表面形貌、截面形貌和磨痕形貌进行分析。结果在摩擦条件下,TiN涂层的开路电位随着滑动摩擦时间的增加而逐渐降低。TiN涂层在不同恒电位(-1V、-0.5 V、OCP、0 V)下滑动摩擦,平均摩擦系数分别为0.392,0.416、0.324、0.348。磨损率分别为1.8117×10-6、3.1123×10-6、4.5958×10-6、7.7724×10-6 mm3/(N·m)。在0.5 V下,涂层被磨穿。TiN涂层在人工海水环境中的主要腐蚀磨损破坏机制为磨粒磨损和疲劳点蚀。结论提高加载电位,涂层的磨损量和磨损率同步增大。在-1、-0.5 V,OCP下,由腐蚀促进磨损的损失量占TiN涂层损失总量的比重逐渐增大,依次为0%、41.78%、61.77%。在0 V时,TiN涂层产生了由磨损促进腐蚀的损失量,占TiN涂层损失总量的比例为6.1%。

Effects of Constant Potential on Corrosive Wear of TiN Coating in Artificial Seawater Environment

The work aims to study effects of different constant potential on corrosive wear behavior of TiN coating in artifi-cial seawater environment. TiN coating was deposited on 316 stainless steel with multi-arc ion plating system. Phase structure,hardness, adhesion, electrochemical properties, friction coefficient and wear rate were evaluated by performing XRD test, na-noindentation hardness test, film-substrate adhesion test, electrochemical workstation test, abrasion test at different constant po-tential and section profile test of coating grinding crack were evaluated. Surface morphology, section morphology and grinding crack morphology of the coatings were analyzed with SEM. Under the friction condition, open circuit potential declined gradu-ally with the increase of sliding friction time. At different constant voltage (-1 V, -0.5 V, OCP, 0 V), average friction coefficient was 0.392, 0.416, 0.324, 0.348, respectively. Wear rate was 1.8117×10-6mm3/(N·m), 3.1123×10-6mm3/(N·m), 4.5958×10-6 mm3/(N·m), 7.7724×10-6mm3/(N·m), respectively. At 0.5 V, the coating was worn out. Main corrosive wear mechanisms of TiN coating in artificial seawater were abrasive wear and fatigue pitting. With the increase of load potential, wear volume and wear rate of TiN coating increase simultaneously. At the potential of (-1 V, -0.5 V, OCP), as corrosion-accelerated wear loss accounts for a higher proportion of total loss, namely 0%, 41.78%, 61.77% and 75.61%. At 0 V, wear-accelerated loss is gener-ated on TiN coating, which accounts for about 6.1% of the total loss.