J. Mater. Sci. Technol. ›› 2020, Vol. 43: 135-143.DOI: 10.1016/j.jmst.2020.01.004

• Research Article • Previous Articles     Next Articles

New para-magnetic (CoFeNi)50(CrMo)50-x(CB)x (x = 20, 25, 30) non-equiatomic high entropy metallic glasses with wide supercooled liquid region and excellent mechanical properties

Kim Jeong Taeab*(), Hong Sung Hwanb, Park Jin Manc, Jürgen Eckertad, Kim Ki Buemb*()   

  1. a Erich Schmid Institute of Materials Science, Austrian Academy of Sciences (ÖAW), Jahnstraβe 12, 8700, Leoben, Austria
    b Hybrid Materials Center (HMC), Department of Nanotechnology and Advanced Materials Engineering, Sejong University, 209, Neungdong-ro, Gwangjin-gu, Seoul, 143-747, Republic of Korea
    c Global Technology Center (GTC), Samsung Electronics Co., Ltd, 129 Samsung-ro, Yeongtong-gu, Suwonsi, Gyeonggi-do, 443-742, Republic of Korea
    d Department of Materials Science, Chair of Materials Physics, Montanuniversität Leoben, Jahnstraße 12, 8700, Leoben, Austria
  • Received:2019-08-05 Accepted:2019-09-18 Published:2020-04-15 Online:2020-04-26
  • Contact: Tae Kim Jeong,Buem Kim Ki

Abstract:

In this study, high entropy metallic glasses (HEMGs) were developed through a combination of concepts for designing metallic glasses (main element + transition metal + metalloid element) and high-entropy alloys (more than five elements, each element having an atomic concentration between 5 at.% and 35 at.%). The developed metallic glass alloys are composed of Co-Fe-Ni main elements, transition metals (Cr, Mo) and metalloid elements (C, B). Moreover, the present work reports the thermal, mechanical and magnetic properties of (CoFeNi)50(CrMo)50-x(CB)x alloys with x = 20, 25, 30. The developed as-spun HEMGs exhibit typical paramagnetic properties even for a high amount of ferromagnetic elements (Co, Fe, and Ni) and have high elastic modulus (103-160 GPa) and hardness (14-27 GPa), thus possessing mechanical properties similar to well-known Co-based metallic glasses (Co-Cr-Mo-C-B system). In addition, some of the bulk samples prepared with a diameter of 2 mm form bulk metallic glasses with a high compressive strength around 3.5 GPa. The mechanisms determining the stability of the supercooled liquid, as well as the paramagnetic and mechanical properties for the developed non-equiatomic HEMGs, are discussed.

Key words: Metallic glasses, Paramagnetism, High entropy alloys, Phase stability