EAGER: External Magnetic Field Assisted Laser Metal Deposition of Highly Oriented Crystalline Ni-Based Alloys

EAGER：外部磁场辅助激光金属沉积高取向晶态镍基合金

• 批准号: 1746147
• 负责人: Jing Shi
• 金额: $ 7.5万
• 依托单位: University of Cincinnati Main Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1746147&HistoricalAwards=false
• 关键词: EAGER; External; Magnetic; Field; Assisted

Directionally solidified nickel-based alloys are widely used as structural materials under extreme environments, where high-temperature strength, thermal creep resistance, and anti-oxidation properties are required. Although additive manufacturing (AM) has become more competitive in manufacturing metal components in recent years, the existing AM methods are still inadequate to fabricate directionally solidified alloys because of the obstacles in controlling crystal nucleation and growth orientations. This EArly-concept Grant for Exploratory Research (EAGER) project investigates fundamental research enabling laser metal deposition to produce highly oriented crystal metals with the help of magnetic fields. It effectively pushes the limit of AM methods to manufacturing high-end structural parts for a number of industries including aerospace, power generation, and automotive, with shorter product development times and enhanced performance, and at affordable costs. The research objective is to investigate the fundamental science of magnetic field effects on crystal orientation of Ni-based alloys in a laser metal deposition process. With the proper design and process parameters, this project's AM method is expected to mitigate or even eliminate the columnar to equiaxed transition phenomenon, and thus it can produce highly oriented crystalline Ni-based alloys with controllable orientation and improved mechanical properties. Crystal orientation control is realized by applying a strong static magnetic field in laser metal deposition, so that the angle between the easy magnetization axis and the preferred growth direction in in line with that between magnetic field and thermal flux. Comprehensive mechanical property measurements and microstructure characterization will be carried out to validate the effectiveness of the method. The crystal orientation control mechanism will provide unprecedented insight on developing a new generation of high performance alloys with controllable microstructure.

定向凝固镍基合金广泛用作极端环境下的结构材料，要求具有高温强度、抗热蠕变性和抗氧化性能。尽管近年来增材制造（AM）在制造金属部件方面变得更具竞争力，但由于控制晶体成核和生长方向方面的障碍，现有的增材制造方法仍然不足以制造定向凝固合金。这个早期概念探索性研究资助 (EAGER) 项目研究基础研究，使激光金属沉积能够在磁场的帮助下生产高度取向的晶体金属。它有效突破了增材制造方法的极限，为航空航天、发电和汽车等多个行业制造高端结构零件，缩短了产品开发时间，提高了性能，并且成本低廉。研究目的是研究激光金属沉积过程中磁场对镍基合金晶体取向影响的基础科学。通过适当的设计和工艺参数，该项目的增材制造方法有望减轻甚至消除柱状到等轴转变现象，从而可以生产出高取向的晶态镍基合金，其取向可控并改善机械性能。激光金属沉积中通过施加强静磁场来实现晶体取向控制，使易磁化轴与择优生长方向之间的角度与磁场和热通量之间的角度一致。将进行全面的机械性能测量和微观结构表征，以验证该方法的有效性。晶体取向控制机制将为开发具有可控微观结构的新一代高性能合金提供前所未有的见解。

项目成果

Texture control of Inconel 718 superalloy in laser additive manufacturing by an external magnetic field

激光增材制造中通过外部磁场控制 Inconel 718 高温合金的织构

• DOI: 10.1007/s10853-019-03569-7
• 发表时间: 2019-03-29
• 期刊: Journal of Materials Science
• 影响因子: 4.5
• 作者: Yachao Wang;Jing Shi
• 通讯作者: Jing Shi