TiC含量对激光熔覆铁基涂层特性的影响

Effect of TiC Content on the Properties of Fe Based Coating by Laser Cladding

采用10 kW光纤激光进行激光熔覆铁基TiC涂层的试验研究,探讨不同TiC含量对铁基熔覆层宏观质量的影响,采用金相显微镜表征熔覆层的组织结构特征,采用MM-U10G型磨损试验机测定熔覆层的耐磨性。结果表明:不同TiC含量粉末得到的激光熔覆层表面成形平整。随着TiC质量分数的提高,熔覆层含Ti量不断提升,开裂倾向加大。当TiC质量分数为0时,熔覆层显微组织主要呈现为枝晶组织,组织较均匀。当TiC质量分数为10%时,出现第二相。随TiC比例的提高,第二相数量增多,且颗粒尺寸更大,分布更密集,熔覆层显微硬度也呈上升趋势。当TiC质量分数为30%时,熔覆层的硬度整体呈现为最高,范围为920~1400 HV。熔覆层的耐磨性也会随着TiC质量分数的提高而提升。

A 10 kW fiber laser was used to conduct the experimental study on the Fe-based TiC coating by laser cladding in this paper.Effect of different TiC content on the macroscopic quality of Fe-based cladding was discussed.Optical microscope was adopted to reveal the microstructure and phase structure of the coatings.Furthermore,a MM-U10 G type friction wear tester was used to measure the wear resistance of the coatings.Results show that,the surface of laser cladding layer with different TiC content is formed smoothly.With the improvement of TiC mass fraction,Ti content of cladding layer increases continuously and the cracking tendency increases.When the TiC mass fraction was 0,the microstructure of the cladding layer was mainly dendrite with uniform microstructure.When the TiC mass fraction was 10%,the second phase occurs.And with the increase of TiC content,the number of the second phase increases,the particle size is larger,the distribution is denser,and the microhardness of cladding layer also increases.When the TiC mass fraction is 30%,the hardness of the cladding layer is the highest overall,which is ranging from 920-1400 HV.The wear resistance of cladding layer is also increasing with the improvement of TiC content.