强磁场下退火提高增材制造Ti-6Al-4V合金力学性能的研究（英文）  

Improved Mechanical Properties of Additive Manufactured Ti-6Al-4V Alloy via Annealing in High Magnetic Field

作　　者：赵瑞峰[1] 李金山[1] 张颖 李佩璇 王嘉祥 邹程雄 唐斌[1] 寇宏超[1] 甘斌 张亮 王军[1] 王毅[1] Zhao Ruifeng;Li Jinshan;Zhang Ying;Li Peixuan;Wang Jiaxiang;Zou Cheng- xiong;-Tang Bin;Kou Hongchao;Gan Bin;Zhang Liang;Wang Jun;William Yi Wang(State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi'an 710072,China;Shanghai Engineering Research Center of 3D Printing Materials,Shanghai 200437,China;Shanghai Research Institute of Materials,Shanghai 200437,China)

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072 [2]上海3D打印材料工程研究中心,上海200437 [3]上海材料研究所,上海200437

出　　处：《稀有金属材料与工程》2018年第12期3678-3685,共8页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China (51690163);National Key Research and Development Program of China (2016YFB0701304,2016YFB0701303);Project to Strengthen Industrial Development at the Grass-Roots Level (TC160A310/19);Shanghai Rising—star Program(18QB1400600).

摘　　要：基于提出的一种崭新的磁场驱动方法有效地提高了激光选区熔化Ti-6Al-4V合金的力学性能。通过X射线衍射、光学显微镜、扫描电子显微镜和原子力显微镜,系统地表征了初始态和在7 T强磁场下退火30 min的样品的微观结构。其中,退火温度分别选取在低于β转变温度的400和800℃,以及高于β转变温度的1200℃。键合电荷密度不仅可以表征由Al和V原子引起的晶格畸变,还可以从电子和原子本质上揭示固溶强化机制和马氏体相变机制。由于退火时间较短,经7T强磁场400和1200℃退火的试样的极限抗拉强度和伸长率均比初始态的试样有所提高。上述结果表明,通过热和磁场的耦合效应,可以预期改变激光选区熔化Ti-6Al-4V合金的相变热力学,进而有效地优化其微观结构。这一设想的验证将有助于开发一种有效提高增材制造材料的力学性能的新型磁场驱动方法。A novel magnetic-field-driving approach was proposed and used to efficiently enhance the mechanical properties of selective laser melting (SLM)Ti-6Al-4V.The microstructures of the as-built and the SLM specimens annealed at 400,800℃ below the β transus,and 1200℃ above the β transus for 30min in the high magnetic field of 7 T were comprehensively characterized in terms of X-ray diffraction,optical microscope,scanning electron microscope,and atomic force microscope.Lattice distortions induced by Al and V atoms were characterized by bonding charge density,providing an insight into the atomic and electronic basis for the solid solution strengthening mechanism and the martensitic transformation mechanism.Referring to the as-built specimens, the ultimate tensile strength and the elongation of annealed specimens at 400 and 1200℃ in 7T high magnetic field increase due to the short annealing time.Based on the coupling effect offorce field induced by the heat and magnetic,it is expected that the microstructures of SLM Ti-6Al-4V would be conventionally optimized through changing the phase transformation thermodynamics. The validation of this hypothesis will pave a path to develop a novel magnetic-field-driving approach efficiently enhancing the mechanical properties of additive manufactured materials.

关 键 词：TI-6AL-4V 激光选区熔化 热处理 键合电子密度 

分 类 号：TG156.2[金属学及工艺—热处理] TG146.23[金属学及工艺—金属学]