Journal of Advanced Chemical Engineering

High coercivity and density Nd-Fe-B sintered magnets fabricated by hot isostatic pressing sintering

2^nd International Conference on Advances in Chemical Engineering and Technology

November 16-17, 2017 | Paris, France

Fang Yang, Zhimeng Guo, Haiying Wang and Junjie Hao

University of Science and Technology Beijing, China

Posters & Accepted Abstracts: J Adv Chem Eng

Abstract:

In this paper, the magnetic properties and microstructure were studied in Nd-Fe-B sintered magnets fabricated by hot isostatic pressing sintering (HIP). The sintering temperature of the magnets by HIP decreased to 1123 K, which was approximately 200 K lower than that of the magnets by vacuum sintering. In addition, the density of the magnets by HIP reached to 7.58 g/ cm3, while that of the magnets by vacuum sintering was 7.59 g/cm3. The microstructure of the magnets was optimized by HIP. The average grain size decreased from 9.09 μm to 7.58 μm, which was effective to enhance coercivity. As a result, the coercivity increased to 14.63 kOe, 8.4% higher than that of the magnets by vacuum sintering. Upon further increasing the sintering temperature of HIP, grain growth was obvious. Consequently, the lower magnetic properties of the magnets were caused.