Microstructure and mechanical properties of high carbon M2 powder metallurgy high-speed steel prepared by the carbide addition

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.

KEYWORDS:

• Powder metallurgy high-speed steel
• carbide
• microstructure evolution
• mechanical properties

Acknowledgements

This research is supported by National Key R&D Program of China (2016YFB0700302).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research is supported by the National Key R&D Program of China [2016YFB0700302].

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.