标题：Effect of boron addition on thermal and mechanical properties of Co-Cr-Mo-C-(B) glass-forming alloys
作者：Kim, Jeong Tae; Hong, Sung Hwan; Bian, Xilei; Gokuldoss, Prashanth Konda; Song, Kaikai; Eckert, Jurgen; Park, Jin Man; Kim, Ki Buem
作者机构：[Kim, Jeong Tae; Bian, Xilei; Gokuldoss, Prashanth Konda; Eckert, Jurgen] Austrian Acad Sci, Erich Schmid Inst Mat Sci, Jahnstr 12, A-8700 Leoben, Aus 更多
通讯作者：Park, Jin Man
通讯作者地址：[Kim, KB]Sejong Univ, Dept Adv Mat Engn, Seoul 143747, South Korea;[Park, JM]Samsung Elect Co Ltd, GTC, 129 Samsung Ro, Suwonsi 443742, Gyeonggi Do, S 更多
关键词：Metallic glasses; Thermal stability; Thermal properties; Mechanical; properties; Casting; Microstructure
摘要：In this work, we investigated the effect of boron addition on glass-forming ability and mechanical properties of Co-Cr-Mo-C alloys. The starting alloy was (Co0.65Cr0.13Mo0.22)(80)C-20 derived from the Co65Cr13Mo22 ternary eutectic composition. This alloy is almost fully crystalline and exhibits brittle mechanical properties. Replacing carbon with boron allows obtaining bulk metallic glasses (BMGs) and bulk metallic glass composites. The designed alloys show very high strength (similar to 4100 MPa), wide super-cooled liquid region (similar to 100 K) and large endothermic enthalpy of the supercooled liquid region (similar to 35 J/g), indicating high thermal stability. The electronegativity difference and supercooled liquid region of the present alloys are comparable to rare-earth elements containing BMGs. The physical properties of the present alloys corresponded well with the alloy design strategy based on the unified parameter using the glass transition temperature, fracture strength, and molar volume. Furthermore, we propose the optimum compositional condition for glass formation by controlling the carbon-to-boron ratio and the influence of carbon on phase formation in this alloy system is discussed.