【作者】 李瑞迪； 周科朝； 袁铁锤； 刘咏； 史玉升； 祝弘滨；

【Author】 Li Ruidi;Zhou Kechao;Yuan Tiechui;Liu Yong;Shi Yusheng;Zhu Hongbin;State Key Laboratory of Powder Metallurgy,Central South University;State Key Laboratory of Material Forming and Mould Technology,Huazhong University of Science and Technology;CRRC Research Institute Co.,Ltd.;

【机构】 中南大学粉末冶金国家重点实验室； 华中科技大学材料成形与模具技术国家重点实验室； 中车工业研究院有限公司；

【摘要】 以探月、火星探测、空间站建设等为代表我国航天事业正蓬勃发展。铝合金激光增材制造(Selective Laser Melting,SLM)较好地契合了航天领域对材质轻量化、结构镂空轻量化的迫切需求,有望成为下一代运载火箭、卫星等核心零部件成形的关键技术。因此,开发出新一代增材制造高强铝合金,已经成为当前航天增材领域亟待完成的一个重要基础研究任务。在国家重点研发计划、国家自然科学基金的支持下,与中车开展合作,针对现有增材制造商用铝合金性能不足难题,提出基于层错能效应发展增材制造铝镁合金新型强韧化机理。针对易裂问题,从SLM铝镁合金的热裂机理出发,揭示了合金成分与凝固应力敏感性因子、层错能及力学性能的关系,发现了激光增材制造高镁含量铝合金中存在9R相。通过抑裂机制-层错能效应强韧化机制-成分设计-疲劳性能-构件质量控制的系统研究,制备了屈服强度520MPa,拉伸强度570MPa,延伸率12%的增材制造铝合金。研发的铝合金粉末已成形出200×200mm的复杂零件,且通过疲劳性能测试,在中车工业获得应用验证。更多还原

【Abstract】 China’s aerospace industry is developing vigorously,represented by lunar exploration,Mars exploration,and space station construction.Aluminum alloy laser additive manufacturing(SLM) meets the urgent needs of the aerospace industry for lightweight materials and hollow structures,and is expected to become a key technology for the formation of core components such as next-generation launch vehicles and satellites.Therefore,the development of a new generation of additive manufacturing high-strength aluminum alloys has become an important basic research task urgently to be completed in the current aerospace additive field With the support of the National Key R&D Program and the National Natural Science Foundation of China,it cooperated with CRRC to address the problem of insufficient performance of the existing additive manufacturing commercial aluminum alloys,and proposed the development of new strengthening and toughening of additive manufacturing aluminum-magnesium alloys based on the stacking fault energy effect.mechanism.Aiming at the problem of easy cracking,starting from the hot cracking mechanism of SLM aluminum-magnesium alloy,the relationship between alloy composition and solidification stress sensitivity factor,stacking fault energy and mechanical properties was revealed,and 9 R was found in laser additive manufacturing of high-magnesium aluminum alloy.Mutually.Through the systematic research of crack suppression mechanism-stacking fault energy effect strengthening and toughening mechanism-composition design-fatigue performance-component quality control,an additively manufactured aluminum alloy with a yield strength of 520 MPa,a tensile strength of 570 MPa and an elongation of 12% was prepared.The aluminum alloy powder developed has been formed into complex parts with a size of 200 x200 mm,and has passed the fatigue performance test,and has obtained application verification in CRRC.更多还原