硬质合金表面Ti系涂层退除后的界面性能研究

采用电弧离子镀技术(AIP)在YW2合金基体表面制备了TiAlN涂层，通过化学方法退除基体上的涂层，分析了硬质合金表面退除涂层后和镀覆涂层前成分和元素存在形态的变化。发现当样品在30%H₂O₂、草酸钾COOK(1.5mol·L-1)、缓蚀剂葡萄糖酸钠GA和NaOH，V_NaOH溶液∶V_30%H2O2∶V_COOK溶液=1∶1∶1，45 ℃时，45 min可以退除涂层，肉眼未观察到基体表面受腐蚀。涂层退除后样品表面光亮，呈现合金未镀覆涂层前颜色。通过对退镀后YW2基体和基体镀覆涂层前的表面XPS定性及定量分析发现，退除涂层后，基体表面W元素结合能和N元素主峰结合能与XPS结合能与参照表上对应结合能变化很小，元素的价态没有发生变化;镀覆TiAlN涂层时扩散到合金浅表层的Al，Ti，N元素，造成表面Al，Ti，N元素含量较镀覆涂层前增加，结合能位置偏移，形成AlN和TiN，有利于重新镀覆的涂层与合金基体的结合。

Study on the Interface Characteristics of Cemented Carbide after Stripping Ti Department Coatings

TiAlN Coatings were stripped by chemical method, which were deposited on YW2 Alloy by arc ion plating. The surface morphology and composition of the cemented carbide after stripping TiAlN coatings by chemistry method were analyzed. It was found that TiAlN coatings on the cemented carbide substrates could be removed by being taken in 30% of hydrogen peroxide and potassium oxalate in alkaline mixed solution(V_{NaOH solution}∶V_30%H2O2∶V_{COOK solution}=1∶1∶1)at 45 ℃ for 45 minutes. The surface of the cemented carbide substrate was bright，and the color was the same as that before depositing TiAlN coatings. The surface of the substrate after removing was studied by X-ray photoelectron spectrum (XPS). The results showed that binding energies of the W element and the main peak of N element on the substrate surface were much close to the criterion binding energy in the XPS data-base; and the valence of the element on the YW2 alloy changed little. The Al, Ti and N elements diffusing into the superficial zone of the sample during the coating depositing process made their contents increase and the band energy location offset after stripping the coating. TiN and AlN were formed, which benefit to increase the film-substrate cohesion during re-preparing coatings. The influence of stripping solution on the corrosion degree of cemented carbide substrate was small.