摘要
目的研究选择性激光熔化(SLM)技术制备的成形钨的微观组织和力学性能。方法采用纯钨粉末作为原材料,利用SLM技术制备了高密度的纯钨试样,系统研究其孔隙与裂纹的形成机理。同时,利用光学显微镜、显微维氏硬度计和压缩实验等分析手段,分别沿水平面(x-y)和垂直平面(z-x)对其微观组织与力学性能进行分析,探究SLM成形纯钨的各向异性。结果成功制备了相对密度为97.79%的高致密纯钨试样,在水平面上,组织主要为呈长条形的柱状晶,在垂直平面上,组织为粗大的胞状晶,断口形貌表现为典型的宏观脆性断裂特征。在水平面上,试样具有更高的抗压强度(1100 MPa)和显微硬度(427±5)HV。结论孔隙的形成主要与Marangoni效应有关,而裂纹的产生主要取决于材料本身的特性和SLM工艺参数。组织的各向异性导致2个平面的力学性能有一定差异。
The work aims to investigate the microstructure and mechanical properties of tungsten fabricated by the Selective Laser Melting(SLM)technology.Pure tungsten powder was employed as the raw material to fabricate high-density tungsten samples through the Selective Laser Melting (SLM) technology. The formation mechanisms of pores and cracks were system-atically studied. Additionally, analysis was carried out with optical microscopy, micro Vickers hardness testing, and compression experiments, from both the horizontal (x-y) and vertical (z-x) planes, to explore the anisotropy of SLM-fabricated tungsten. The experimental outcomes demonstrated the successful fabrication of highly dense pure tungsten samples with a relative density of 97.79%. The microstructure analysis revealed elongated columnar crystals in the horizontal plane, whereas a coarser cellular structure was observed in the vertical plane. The fracture surface exhibited typical macroscopic brittle fracture characteristics. Moreover, in the horizontal plane, the samples exhibited superior compressive strength (1 100 MPa) and microhardness (427±5)HV. Pore formation is primarily affected by the Marangoni effect, while crack generation is mainly governed by material characteristics and SLM process parameters. The anisotropy in microstructure leads to mechanical property variations in the two planes.
作者
苏玉东
汪志勇
范小松
马建国
吴杰峰
朱协彬
翟华
SU Yu-dong;WANG Zhi-yong;FAN Xiao-song;MA Jian-guo;WU Jie-feng;ZHU Xie-bin;ZHAI Hua(School of Materials Science and Engineering,Anhui Polytechnic University,Anhui Wuhu 241000,China;University of Science and Technology of China,Hefei 230026,China;Institute of Plasma Physics,Hefei Institute of Physical Sciences,Chinese Academy of Sciences,Hefei 230031,China;Anhui Provincial Key Laboratory of Special Welding Technology,Anhui Huainan 232063,China;Anhui Province Key Lab of Aerospace Structural Parts Forming Technology and Equipment,HFUT,Hefei 230009,China)
出处
《精密成形工程》
北大核心
2023年第9期168-174,共7页
Journal of Netshape Forming Engineering
基金
中国科学院合肥物质科学研究院院长基金(YZJJ2022QN25)
等离子体所科学基金(DSJJ-2021-06)
中央高校基本科研业务费专项资金(PA2022GDSK0058)。
关键词
钨
SLM
致密度
显微硬度
抗压强度
tungsten
SLM
density
microhardness
compressive strength
