ABSTRACT

In this study, monolayer TiN and multilayer TiN/Ti coatings involving different modulation ratios were deposited on Ti–6Al–4V substrate. Ti interlayers in the multilayer TiN/Ti coatings were prepared under gradient negative bias of –800, –600, and –400 V, with corresponding durations of 2, 2, and 1 min. Mechanical properties and crack' s resistance of the coatings were explored. Damage morphology of coating cross-section was characterized by the focused ion beam (FIB) method. Finite element modelling was used to analyse the stress field. Multilayer TiN/Ti coatings show better impact resistance than monolayer TiN coating. Tensile stress decrease with the increase of interfaces. Gradient bias Ti interlayers restrain crack propagation by cracks deflection and branch. Erosion resistance was evaluated by sand erosion test. Crack propagation and connection account for the coatings failure: the deeper the crack propagation, the higher the erosion rate.

摘要

在这项研究中，涉及不同调制比的单层 TiN 和多层 TiN/Ti 涂层沉积在 Ti-6Al-4V 基板上。多层 TiN/Ti 涂层中的 Ti 夹层是在 –800、–600 和 –400 V 的梯度负偏压下制备的，相应的持续时间为 2、2 和 1 分钟。研究了涂层的机械性能和抗裂性。通过聚焦离子束（FIB）方法表征涂层横截面的损伤形态。有限元建模用于分析应力场。多层 TiN/Ti 涂层显示出比单层 TiN 涂层更好的抗冲击性。拉伸应力随着界面的增加而降低。梯度偏置 Ti 夹层通过裂纹偏转和分支来抑制裂纹扩展。耐蚀性通过砂蚀试验评价。