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.

在极端环境下，基于固化的镍基合金被广泛用作结构材料，在这种环境下，需要高温强度，耐热性抗性和抗氧化特性。尽管近年来添加剂制造（AM）在制造金属组件方面变得更有竞争力，但由于控制晶体成核和生长方向的障碍，现有的AM方法仍然不足以制造方向固化的合金。这项探索性研究（急切）项目的早期概念赠款研究了基础研究，从而使激光金属沉积在磁场的帮助下生产高度取向的晶体金属。它有效地将AM方法的限制推向了许多行业的高端结构零件，包括航空航天，发电和汽车，产品开发时间较短，性能增强，并且以实惠的价格成本。研究目标是研究磁场对在激光金属沉积过程中基于Ni的合金晶体方向的基础科学。借助适当的设计和过程参数，该项目的AM方法有望减轻甚至消除圆柱的均值过渡现象，因此它可以产生具有可控方向和改善机械性能的高度取向的结晶基合金。通过在激光金属沉积中施加强静电场来实现晶体方向控制，从而使易于磁化轴与首选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提供前所未有的见解，以开发具有可控微结构的新一代高性能合金。

项目成果

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

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