| 引用本文: | 郭溪溪,路媛媛,林守钢,赖境,刘德健.ZrO2陶瓷颗粒在激光作用下组织形貌演变规律[J].材料科学与工艺,2019,27(2):22-28.DOI:10.11951/j.issn.1005-0299.20180072. |
| GUO Xixi,LU Yuanyuan,LIN Shougang,LAI Jing,LIU Dejian.The evolution mechanism of morphology and microstructure of ZrO2 ceramic powders under laser irradiation[J].Materials Science and Technology,2019,27(2):22-28.DOI:10.11951/j.issn.1005-0299.20180072. |
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| 摘要: |
| 采用激光表面处理技术制备ZrO2复合热障涂层可使陶瓷颗粒与金属之间实现冶金结合，增加结合强度，但由于陶瓷颗粒和金属热膨胀系数之间的差异，制备大面积复合热障涂层仍存在比较严重的开裂问题.为降低复合材料层的开裂倾向，更好地控制ZrO2陶瓷颗粒的离散规律，本文针对激光熔注过程中陶瓷颗粒的熔化问题，采用高速摄像、扫描电子显微镜研究了氧化锆陶瓷颗粒进入熔池前后激光对其形貌与离散规律的影响规律.结果表明，在激光能量密度较低的情况下，激光直接作用于氧化锆陶瓷颗粒会导致单个ZrO2陶瓷颗粒发生裂解现象；当激光能量密度高于2.5 J/mm2时，ZrO2陶瓷颗粒熔化严重并发生球化现象.在激光熔注过程中，由于受到激光和高温熔池的双重作用，氧化锆陶瓷颗粒内部晶粒长大，高能量大尺寸晶界促进了Ti熔体向ZrO2陶瓷颗粒内部扩散. |
| 关键词: 激光 氧化锆 形貌 复合材料 高速摄像 |
| DOI：10.11951/j.issn.1005-0299.20180072 |
| 分类号:TG174.45 |
| 文献标识码:A |
| 基金项目:"十三五"装备预研共用技术项目(41423030503). |
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| The evolution mechanism of morphology and microstructure of ZrO2 ceramic powders under laser irradiation |
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GUO Xixi1, LU Yuanyuan2, LIN Shougang1, LAI Jing1, LIU Dejian1
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(1. School of Material Science and Engineering,Huazhong University of Science and Technology, Wuhan 430074,China; 2. Hubei University of Technology Engineering and Technology College, Wuhan 430064, China)
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| Abstract: |
| The ZrO2 composite thermal barrier coating prepared by laser surface treatment technology can achieve metallurgical bonding and increase bonding strength between ceramic particles and metal. However, there are still serious cracking problems in the preparation of large-area composite thermal barrier coatings due to the difference between the thermal expansion coefficients of ceramic particles and metals. To reduce the cracking tendency of the composite layer and control the dispersion rule of ZrO2 ceramic particles during the laser melt injection process, the effect of the laser irradiation on the morphology and dissociation of ZrO2 ceramic particles before and after being injected into the molten pool was studied by high-speed camera and scanning electron microscopy. The results show that cracking of the ZrO2 ceramic particle occurred when the laser beam was irradiated onto the ZrO2 ceramic particles with a lower energy density, while serious melting and spheroidization of the ZrO2 ceramic particles happened when the laser energy density is higher than 2.5 J/mm3. During the laser melt injection process, the grain size of ZrO2 ceramic particles increased clearly due to the action of the laser beam and high temperature molten pool, and the large grain-boundary with high energy promoted the infiltration of Ti melt into the ZrO2 ceramic particles |
| Key words: laser ZrO2 morphology composite material high-speed camera |
