镀铝石墨烯/铝基复合粉末制备及其选择性激光熔化成形基础研究

The grapheme exhibits high strength, high toughness and high electrical conductivity, etc. The addition of grapheme could improve the comprehensive properties of the Al alloys, which makes it have promising prospects in applications such as mechanical, optical, thermal,electrical and other aspects. But there is density difference and poor wet between grapheme and Al, the grapheme easily agglomerates in Al matrix. It is difficult to prepare graphene/Al matrix composite powder for selective laser melting (SLM), which restricts its application in SLM additive manufacturing field. At present, the research on SLM forming of graphene/Al composite powder is less.. The project puts forward a method for coating Al on grapheme through organic aluminum chemical reduction, and combining milling under vacuum to prepare graphene/Al composite powders. Study thermodynamics and kinetics of chemical reduction reactions during which Al is coated on grapheme, and realize precision control of the process. Study the dispersion principle of grapheme in Al matrix during milling under vacuum, and provide theory guidance for preparation graphene/Al based composite powers. Study the solidification mechanism and interfacial bonding mechanism between grapheme and Al during SLM process, realize control of the microstructure and interfacial bonding strength, and prepare the high-performance graphene/Al composites. The project is intended to lay the groundwork for future research.

石墨烯具有高强度、高韧性和高导电性等优点，将其添加到铝合金中，可有效改善铝合金的综合性能，使其在力学、光学、热学、电学等方面具有重要应用潜力。由于石墨烯与铝密度相差大，润湿性差，在铝基体中易团聚，难以制备选择性激光熔化(SLM)成形用石墨烯/铝基复合粉末，制约其在SLM增材制造领域的应用，所以目前国内外对石墨烯/铝基复合粉末SLM成形的研究较少。. 本项目采用有机铝化学还原法对石墨烯表面镀铝，结合真空球磨法制备SLM成形用石墨烯/铝基复合粉末。通过研究石墨烯镀铝化学还原反应热力学及动力学行为，实现对镀铝过程的精确控制；研究球磨过程中石墨烯在铝基体中的分散规律，为制备铝基复合粉末提供指导。对石墨烯/铝基复合粉末SLM成形过程中凝固行为、石墨烯与基体界面结合机理进行研究，实现对SLM成形过程凝固组织及界面结合强度的控制，制备高性能石墨烯/铝基复合材料，为该技术的工程应用打下基础。

石墨烯具有高强度、高韧性和高导电性等优点，将其添加到铝合金中，可有效改善铝合金的综合性能，使其在力学、光学、热学、电学等方面具有重要应用潜力。由于石墨烯与铝密度相差大，润湿性差，在铝基体中易团聚，难以制备选择性激光熔化（SLM）成形用石墨烯/铝基复合粉末，制约其在增材制造领域的应用。本项目针对上述问题开展了大量研究，按照研究计划圆满完成了项目任务，取得的主要成果如下：.（1）提出了有机铝化学还原法对石墨烯表面镀铝，获得了石墨烯镀铝化学还原反应热力学及动力学行为。.（2）获得了球磨过程中石墨烯在铝基体中的分散规律，为制备铝基复合粉末提供了指导。.（3）揭示了石墨烯/铝基复合粉末SLM成形过程中凝固行为。.（4）揭示了石墨烯与基体界面结合机理。.（5）制备了高性能石墨烯/铝基复合材料。. 项目执行过程中发表SCI收录论文16篇，其中ESI热点/高被引论文2篇，授权发明专利12项，项目组成员参加国内会议2次，做大会特邀报告1次，获分会优秀报告1次，邀请国外专家交流访问4人次。获得中国有色金属工业科学技术奖一等奖1项、山西省自然科学奖二等奖1项。培养硕士研究生7名，博士生2名。