激光熔覆H13-TiC复合涂层的力学性能测试与数值模拟

为提高热作模具钢的使用性能和寿命，利用激光熔覆技术在H13钢表面制备了H13-TiC复合涂层，研究了不同TiC含量下H13-TiC复合涂层的力学性能，并分析了各试样拉伸后的断口形貌。结果表明：激光熔覆后熔覆层硬度、强度都明显高于基体硬度、强度，这是熔覆层中弥散和细晶强化共同作用的结果；熔覆层的断裂机制是脆性断裂和塑性断裂的混合型。最后，基于Mori-Tanaka平均场理论，分析了颗粒增强H13-TiC复合涂层的弹塑性性能，理论预测与实验结果基本吻合。

Measurement and Numerical Simulation of Mechanical Properties for Laser Clad H13-TiC Composite Coatings

In order to improve the performance and longevity of the die steel, H13-TiC composite layers were made by laser cladding on the H13 die steel substrates. The influences of TiC content on mechanical properties of H13-TiC composite layer were studied. The fracture surfaces of various tensile specimens were analyzed respectively. The results indicate that the strength and hardness of the composite layers are obviously improved compared with the parent metal owing to the combined action of dispersive strength and thin grain of TiC, and the brittle fracture as well as the ductile fracture were found in the fracture of composite layers. And then, the elasto-plastic properties of the H13-TiC composite layers were discussed based on Mori-Tanaka method, the results show that the predictions of the model agree with experiments well.