氧化锆掺杂激光熔覆涂层成形、结构与增韧机制

本文利用氧化锆陶瓷在不同凝固成形条件下具有相结构变化的特点,将其作为激光熔覆涂层的增韧相.激光熔覆试验结果表明含氧化锆增韧激光熔覆涂层成形关键在于控制熔池熔体的流动性,低的激光线功率密度有助于分层现象的消除:扫描电镜和能谱分析表明氧化锆陶瓷在熔覆层中没有显著的富集,且点状弥散分布较均匀,同时XRD图谱证明激光熔覆层中氧化锆为单斜相结构,达到了利用氧化锆相变消除残余热应力裂纹的目的,从而可以解决激光熔覆裂纹产生的关键问题.

Study on the forming,structure and toughening mechanism of coating intermingled with ZrO2 by laser cladding

Under different solidification condition,ZrO2 ceramic had different phase-structure properties.therefore,it was used for the toughening phase of coating of laser cladding in this paper.The results of cladding tests showed that coating forming of laser cladding containing depended on the flow properties,and lower laser power density was helpful to avoid delamination phenomena of coating material.SEM and EDS analyzing indicated ZrO2 ceramic didn't have notable enrichment,but its distributing were uniformity in cladding coating.At one time,XRD Spectrum proved phase structure of ZrO2 ceramic in cladding coating was monoclinic,it could avoid residual hot stress by means of phase transformation of ZrO2 ceramic,so that the key problem about the crack in laser cladding was solved.