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在热作模具钢H13基体上通过激光熔覆制备出TiC/H13复合涂层,研究不同TiC含量对复合涂层抗回火(600℃)性能的影响。利用扫描电镜、能谱仪和显微硬度计对激光熔覆涂层回火前后的组织、成分、硬度进行了对比分析和测试。TiC质量分数小于25 wt.%时,涂层与基体之间保持良好的结合,没有出现明显缺陷,当质量分数为25 wt.%时,颗粒周围出现微裂纹。能谱分析表明复合涂层中的颗粒主要成分是Ti和C。激光熔覆TiC/H13复合涂层回火处理10h和回火前对比,晶粒明显长大,随着TiC含量增加,涂层晶粒越细小,TiC弥散分布于晶界处,抑制枝晶的生长,起到细化晶粒的效果;回火20h和回火10h的对比发现晶粒长大不明显。硬度测试显示随着TiC质量分数的增加,熔覆层硬度明显增加,回火后仍保持很高的硬度。
The TiC / H13 composite coatings were prepared by laser cladding on hot-work die steel H13, and the effect of different TiC content on the anti-tempering (600 ℃) properties of the composite coating was studied. The microstructure, composition and hardness of the laser cladding coatings before and after tempering were analyzed and compared with SEM, EDS and microhardness tester. TiC mass fraction of less than 25 wt.%, The coating and the substrate to maintain a good combination of no obvious defects, when the mass fraction of 25 wt.%, Micro-cracks around the particles. EDS analysis showed that the main components of the composite coating particles are Ti and C. The laser cladding TiC / H13 composite coating tempering 10h after tempering compared with the pre-tempering, the grain grew obviously, with the TiC content increased, the smaller the grain size of the coating, TiC dispersed in the grain boundary, the inhibition of dendrite Growth, played the role of grain refinement; tempering 20h and tempering 10h comparison found that grain growth is not obvious. Hardness test shows that with the increase of TiC mass fraction, the hardness of cladding layer increases obviously, and remains high after tempering.