ABSTRACT
This paper used carbonyl iron powder and carbide powder as raw materials to prepare high carbon M2 powder metallurgy high-speed steel through the cold compaction-sintering method. The evolution of microstructure and properties of the material at different sintering temperatures were emphatically studied. The results show that: The microstructure of the samples is that different types of carbides are uniformly dispersed in the matrix. Since the dissolution of the original carbides is a continuous process, the precipitated carbides are constantly changing with the increase of sintering temperature. Moreover, M2 steel achieves sintering densification near the solidus temperature, the sintering window is expanded to 10–15°C. In the sintering temperature range, the carbides in the samples are fine and uniformly dispersed. The material sintered at 1225°C has the best mechanical properties, with a bending strength of 2754 MPa, and a hardness of 51 HRC. In addition, mechanical properties are greatly improved by heat treatment.
Acknowledgements
This research is supported by National Key R&D Program of China (2016YFB0700302).
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No potential conflict of interest was reported by the author(s).
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Notes on contributors
Junhao Yang
Junhao Yang is currently a PhD student of Central South University. His research interests are Fe-based powder metallurgy materials and materials characterisation.
Rutie Liu
Rutie Liu is a Professor of Central South University. His research interests mainly focus on Fe-based powder metallurgy materials, Cu-based powder metallurgy friction materials and porous materials.
Xiang Xiong
Xiang Xiong is a Professor of Central South University. His research interests are in the fields of advanced powder metallurgy material preparation techniques and ceramic matrix composites.
Huaizhuang Luan
Huaizhuang Luan is a PhD student of Central South University.
Yanrong Hao
Yanrong Hao is a graduate student of Central South University.
Baozhen Yang
Baozhen Yang is a PhD student of Central South University.
Jie Chen
Jie Chen is an Associate Professor of Central South University. Her research interests are Cu-based powder metallurgy friction materials and porous material.