选区激光熔化铝合金及其复合材料的研究进展

Research Progress of Selective Laser Melting of Aluminum Alloy and Composites

颗粒增强铝基复合材料因其高比强度、比刚度及优异的耐腐蚀性能等特点,在航空航天等领域应用前景广阔。选区激光熔化技术(SLM)为其提供了一种高效、经济、绿色的制备方式,但该技术对工艺控制水平要求极高,成形过程中粉末构成、激光功率、扫描速度及设备条件等因素对成形产品组织和性能的影响巨大。本文介绍了SLM的基本原理和各个工艺参数对熔池性能的影响,归纳总结了铝合金和铝基复合材料熔池的形成过程,讨论了SLM过程的组织演化和相关参数及增强颗粒等因素对微观组织和性能演化的影响,另外还专门介绍了新兴的外加物理场辅助的增材制造技术。最后,分析了SLM技术目前存在的问题,并展望了未来研究的趋势。

Particle reinforced aluminum matrix composites have the characteristics of high specific strength,specific stiffness and excellent corrosion resistance.It has broad application prospects in aerospace and other fields.Selective laser melting(SLM)technology provides an efficient,economical and green fabrication method for it.However,the technology has extremely high requirements on the level of process control.During the forming process,factors such as powder composition,laser power,scanning speed and equipment conditions have a great influence on the microstructure and properties of the formed products.In this paper,the basic principle of selective laser melting and the influence of various process parameters on the performance of molten pool are introduced.The formation process of molten pool of aluminum alloy and aluminum matrix composites is summarized.The microstructure evolution of selective laser melting process and the influence of related parameters and reinforced particles on the evolution of microstructure and properties are discussed.Additionally,the emerging additive manufacturing technologies assisted by an applied physical field are specifically presented.Finally,the current problems of SLM technology are analysed and future research trends are envisaged.