赵大可,吴东江,牛方勇,马广义.激光能量输入对直接激光沉积莫来石陶瓷组织性能的影响[J].稀有金属材料与工程,2021,50(3):1007~1015.[Zhao Dake,Wu Dongjiang,Niu Fangyong,Ma Guangyi.Effect of laser energy input on microstructure and properties of directed laser deposition mullite ceramics[J].Rare Metal Materials and Engineering,2021,50(3):1007~1015.]
激光能量输入对直接激光沉积莫来石陶瓷组织性能的影响
投稿时间:2020-05-03  修订日期:2020-07-06
中文关键词:  增材制造  陶瓷  激光能量密度  孔隙  力学性能
基金项目:国家自然科学基金项目(面上项目,重点项目,重大项目);中央高校基本科研业务项目;辽宁省自然科学基金指导计划项目
中文摘要:
      直接激光沉积是一种重要的激光增材制造技术,在制备高熔点熔体自生氧化物陶瓷领域得到越来越多的应用。由于对激光增材制造陶瓷在不同激光能量作用下的影响规律及其内在机制理解不足,该技术更广泛的应用受到限制。为此,本文深入研究了激光能量密度对直接激光沉积熔体自生莫来石陶瓷孔隙/密度、微观组织和力学性能的影响。结果表明,较低激光能量密度(15 J/mm2)所制备的陶瓷样件边缘分布有尺寸较大的气孔,使得样件整体孔隙率较高,且表面粘粉严重,这与成形扫描速度大和硅酸盐熔体粘度高有关。而较高激光能量密度(90 J/mm2)虽然可以获得表面光滑、莫来石晶粒尺寸较小的陶瓷样件。但由于单位时间内输入熔池能量高,粉末蒸发产生的气孔来不及逃逸出熔池,使得样件心部形成较大的气孔,限制了样件的力学性能。在激光能量密度为45 J/mm2时,获得了表面相对光洁、孔隙率较低和力学性能较高的莫来石陶瓷样件。本文结果为直接激光沉积增材制造高性能陶瓷过程中合理选定工艺条件提供了理论指导及技术支撑。
Effect of laser energy input on microstructure and properties of directed laser deposition mullite ceramics
英文关键词:Additive manufacturing  ceramics  laser energy density  porosity  mechanical properties
英文摘要:
      Directed laser deposition is a significant laser additive manufacturing technology, and it has been widely utilized in the field of preparing high melting point melt growth oxide ceramics. Due to inadequate understanding of the influence law and internal mechanism of laser additive manufacturing ceramics under the action of different laser energy, the wider application of this technology is limited. In this study, the effects of laser energy density on the porosity/density, microstructure, and mechanical properties of directed laser deposition melt growth mullite ceramics were investigated. The results show that the mullite ceramic samples prepared with lower laser energy density (15 J/mm2) have large pores distributed on the edges, making the porosity of the specimen higher. The sample surface has serious sticky powder, which is related to the high scanning speed and the high viscosity of the silicate melt. The ceramic samples with a smooth surface and smaller mullite grain size were prepared by higher laser energy density (15 J/mm2). However, due to the high energy input into the molten pool per unit time, the pores generated by the evaporation of the powder are too late to escape from the molten pool, resulting in larger pores in the core of the sample, deteriorating the mechanical properties of the samples. The mullite ceramic samples with a relatively smooth surface, low porosity, and high mechanical properties can be obtained when the laser energy density is 45 J/mm2. The results of this study provide theoretical guidance and technical support for the rational selection of process conditions in the process of manufacturing high-performance ceramics with directed laser additive manufacturing.
作者单位E-mail
赵大可 大连理工大学精密与特种加工教育部重点实验室 zhdk_2018@mail.dlut.edu.cn 
吴东江 大连理工大学精密与特种加工教育部重点实验室  
牛方勇 大连理工大学精密与特种加工教育部重点实验室 niufangyong@dlut.edu.cn 
马广义 大连理工大学精密与特种加工教育部重点实验室  
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