Densification Behavior and Microstructure Evolution of Mo Manocrystals by Microwave Sintering

Ruihu Wang,1,2

Shilei Li,1

Peng Hu,1,*Email

Shuqun Chen,1

Jinshu Wang1,*Email

1Key Laboratory of Advanced Functional Materials, Education Ministry of China, Faculty of Materials and Manufacture, Beijing University of Technology, Beijing, 100124, China

2School of Metallurgical Engineering, Xi’an University of Architecture and Technology, Shaanxi, 710043, China

Abstract

Fabrication of full-densified Mo metal with fine grain size and uniform microstructure is highly desired to improve its mechanical property. In this work, microwave-field-assisted thermal sintering was utilized to promote the fast densification of Mo nanocrystals, and the compact with high relative density of 99.8 % and fine grain size of 2.09 μm was obtained at 1450 °C for 0.5 h with heating rate of 20 °C/min, which is much superior to the compact with density of 99.13 % and grain size of 7 μm fabricated by traditional thermal sintering at 1500 °C for 1 h. Further theoretical and experimental investigation reveals that effective volume heating transfer with low activation energy provides strong driven-force for densification of nanosized Mo powder at low temperature.

Densification Behavior and Microstructure Evolution of Mo Manocrystals by Microwave Sintering