激光合金化引入亚微米MC型增强相的研究

为了研究不同反应方式的原位合成或直接添加所引入的碳化物增强相对碳化物强化铁基复合涂层耐磨性能的影响,采用CO2激光器在T10钢表面激光合金化制备TiC/Fe基复合涂层,对涂层的组织结构、显微硬度和耐磨性能进行了检测和分析。结果表明,合金化层组织致密无缺陷,由γ-CrFe7C0.5相+亚微米MC相(M=Ti,Cr,W)组成,其中奥氏体在磨损过程中由于加工硬化转变成马氏体;直接添加增强相的磨损失重是原位合成反应生成增强相的2倍～3倍;Ti+C化合反应生成的碳化物含量高于TiO2+C还原反应,耐磨性能更优异。该实验结果对制备TiC强化Fe基复合涂层时陶瓷相的最佳引入方式,有一定的指导借鉴作用。

Submicron MC-type reinforced coating produced by laser alloying

In order to study the influence of carbides produced by in situ synthesis of various chemical reactions or direct addition on wear resistance of carbide reinforced composite coatings, TiC reinforced Fe-based composite coatings were prepared on T10 steel substrate by laser alloying. Then their microstructures, phases, microhardness and wear properties were investigated and analyzed. Results showed that compact and non-defective alloy layers were obtained, consisting of γ-CrFe7C0.5 and submicron MC(M＝Ti, Cr, W) particles. Austenite transformed into martensite in wear testing because of processing hardening. Wear weight loss of direct addition was 2 times to 3 times larger than that of in situ synthesis. The content of carbides produced through combination reaction between Ti and C was higher than that produced through reduction reaction between TiO2 and C, which led to a better tribological performance. The results can serve as a guide in selecting the best method of the ceramic phase introduction when preparing TiC reinforced Fe-based composite coatings.