Densification and crack suppression in selective laser melting of pure molybdenum

作者：Wang, Dianzheng; Yu, Chenfan; Ma, Jing; Liu, Wei^*; Shen, Zhijian^*

来源：Materials and Design, 2017, 129: 44-52.

DOI：10.1016/j.matdes.2017.04.094

• Selective laser melting
• Pure molybdenum
• Powders spheroidization
• Crack growth
• Grain boundary structure

In this study, dense and crack-free pure Mo has been fabricated by selective laser melting. In order to obtain densification, the precursor powders were granulated and processed by plasma spheroidization. Parts of density of 10.16 g/cm(3) (99.1% of theoretical density) were obtained with spherical powders because of its increased laser absorptivity and packing density. The crack growth behaviors under various scanning strategies are analyzed by electron backscattered diffraction. The interlocking grain boundary structure, which increased the crack growth resistance and caused crack deviation, is formed under layer-wise rotated laser scanning. Cracks can be fully suppressed by applying the designed supporting structure. This study provides a novel route for the fabrication of complex Mo parts.

• 出版日期2017-9-5
• 单位清华大学