The ZrB₂-ZrC composite coating fabricated by ZrB₂-ZrC powder shows low density and poor properties. To improve the quality of ZrB₂-ZrC composite coating, Zr-B₄C powder was used as precursor and the ZrB₂-ZrC composite coating was successfully synthesized in situ on the surface of titanium alloy. The microstructure evolution and reaction mechanism of the Zr-B₄C composite powder in plasma spraying process were investigated. The microstructure and properties of the ZrB₂-ZrC composite coatings fabricated by ZrB₂-ZrC and Zr-B₄C composite powders were investigated comparatively. The results indicate that a dense and fine grain microstructure was formed in the in situ synthesized ZrB₂-ZrC composite coating, and the quality and properties of the coating were improved, which is attributed to the reaction between Zr and B₄C and then the improved melting degree of the powder during the plasma spraying process.

由ZrB ₂ -ZrC粉末制备的ZrB ₂ -ZrC复合涂层表现出低密度和差的性能。为了提高ZrB ₂ -ZrC复合涂层的质量，以Zr-B ₄ C粉末为前驱体，成功地在钛合金表面原位合成了ZrB ₂ -ZrC复合涂层。研究了Zr-B ₄ C复合粉末在等离子喷涂过程中的微观结构演变和反应机理。ZrB ₂ -ZrC和Zr-B ₄制备的ZrB ₂ -ZrC复合涂层的组织和性能对C复合粉进行了比较研究。结果表明，在原位合成的ZrB ₂ -ZrC复合涂层中形成了致密细晶粒的组织，涂层的质量和性能得到了改善，这归因于Zr与B ₄ C之间的反应。在等离子喷涂过程中改善了粉末的熔融度。