自蔓延TiC/Ni功能梯度涂层热熔损性能研究

Erosion Behavior of TiC/Ni Functionally Gradient Coating by SHS/PHIP

利用自蔓延高温合成结合准热等静压技术(SHS/PHIP),在H13钢表面成功制备了TiC/Ni梯度功能涂层。在700℃铝液中对涂层进行0.5h和2h的静态热熔损试验,采用XRD分析熔损涂层的物相,采用SEM-EDS观察熔损涂层的组织并分析成分。结果表明,熔损涂层的主要物相为TiC、Ni、TiO_2和AlNi_3。涂层表层失效原因为Ni粘结相被浸蚀以及TiC骨架结构被氧化。涂层内部以侵蚀Ni粘结相为主,TiC骨架仍保持原有组织结构。TiC耐铝液浸蚀性能强于Ni粘结相。

The TiC/Ni functionally gradient coating on H13 steel surface was prepared by self-propagating high temperature synthesis and pseudo hot isostatic pressing（SHS/PHIP）.TiC/Ni functionally gradient coatings were measured in melted aluminum for 0.5 hand 2 hstatic erosion test at 700 ℃.The coating phases after erosion were analyzed by XRD,and the microstructure and composition of the coatings were observed by SEM-EDS.The results show that the main phase of the coating is composed of TiC,Ni,TiO2 and AlNi3.The surface failure of coating is attributed to the corroded Ni binder phase and the oxidized TiC framework.The subsurface failure of coating is mainly caused by the erosion of Ni binder phase,while the TiC framework remains the original structure.The erosion resistance of TiC is better than that of Ni binder phase.