FeCoCrNiMo high-entropy alloys prepared by powder metallurgy processing for diamond tool applications

ABSTRACT

High-entropy alloys (HEAs) show good mechanical properties like high strength, hardness and wear resistance, and this makes them attractive for application in diamond tools. However, there are severe obstacles to improving the mechanical properties of normal diamond tools with metal-matrix alloys. Here, we report the formation of FeCoCrNiMo HEAs by powder metallurgy processing, starting from a gas-atomised powder followed by mechanical milling and consolidation by spark plasma sintering. Our results show that FeCoCrNiMo HEAs with pure FCC phase can be obtained by this method. Specimens with higher hardness can be obtained at higher temperatures and low pressures, while specimens with higher bending strength are formed at lower temperatures and pressures. FeCoCrNiMo HEAs have remarkably higher hardness and better wear behaviour than metal-matrices commonly in used diamond tools, which indicates that a new type of diamond tool with superior properties can be realised from HEAs.

Special theme block on high entropy alloys, guest edited by Paula Alvaredo Olmos, Universidad Carlos III de Madrid, Spain, and Sheng Guo, Chalmers University, Gothenburg, Sweden.

KEYWORDS:

• High-entropy alloys
• gas-atomised
• mechanical milling
• spark plasma sintering
• wear behaviour

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Mingyang Zhang Ph.D. candidate, Powder Metallurgy Research Institute, Central South University, Changsha, People's Republic of China.

Wei Zhang Ph.D, Associate Professor Powder Metallurgy Research Institute, Central South University, Changsha, People's Republic of China.

Yong Liu Ph.D Professor & Director, Powder Metallurgy Research Institute, Central South University, Changsha, People's Republic of China.

Bin Liu Ph.D Associate Professor, Powder Metallurgy Research Institute, Central South University, Changsha, People's Republic of China.

Jingshi Wang Master, Powder Metallurgy Research Institute, Central South University, Changsha, People's Republic of China.

Additional information

Funding

This work was supported by National Natural Science Foundation of China: [grant number 51201185]; Postdoctoral Foundation Supported Project of CSU  [grant number 148700].