梯度复合材料激光熔化沉积成形的研究进展

高性能梯度复合材料是为克服现有单一均质材料无法满足某些特殊性能要求或为充分发挥不同材料的性能潜力而发展的一类新型复合材料，其显著特征是材料的组分、结构及物性参数根据需要呈连续或梯度变化。激光熔化沉积成形技术采用逐点连续添加材料成形，赋予了该技术在材料组成、凝固组织、外形尺寸等控制上的极大柔性，是未来发展集材料设计、制备、成形及组织性能控制于一体的材料智能制备与成形技术的重要方向。着重介绍采用激光熔化沉积成形技术制备镍系、钛系梯度复合材料方面取得的最新研究进展，通过分析存在的问题和面临的挑战，指出了未来工作的主要方向。

Research Progress on Laser Direct Deposition of Gradient Composites

Advanced high performance gradient composites are one kind of new composites, which are developed to overcome the property limitation of homogeneous structure or expound the property potential of different materials. Their prominent characteristics represent as composition, microstructure and physical properties changing continuously or gradually as required. Laser melting deposition is a new additive manufacturing process. It provides great flexibility in control of materials composition, solidified microstructure, shape and dimensions and becomes an important development trend in integration and intelligent control which combines materials design, fabrication, forming, as well as microstructure and properties tailoring. In this paper, recent advances on gradient composites from Ni and Ti alloys prepared by laser direct deposition are introduced. Finally, some considerations for future research work are pointed out based on analysis of related problems and challenges.