Identifying the significance of Sn addition on the tribological performance of Ti-based bulk metallic glass composites

Tailoring the properties of an engineering material with low coefficient of friction (COF) and high wear resistance has been a long goal in the tribological research. It is particularly true for the bulk metallic glass composites (BMGCs), which are promising for a large range of advanced applications. Although the materials design and mechanical properties have been extensively investigated, knowledge of their tribological behaviors is still lacking. Ball-on-block wear tests were thus conducted to investigate the effect of Sn addition on the tribological behaviors of Ti45Zr25Nb6Cu5Be17 BMGCs under different normal loads. Nano-indentation and nano-scratch tests were carried out to study the phase-specific wear properties of the crystalline dendrite and amorphous matrix in BMGCsrespectively. Preferred wear and delamination in the dendrite phase as a result of the plastic mismatch between the two constituent phases is responsible for the abrasive wear in the Ti47Zr25Nb6Cu5Be17 and Ti46Zr25Nb6Cu5Be17Sn1 BMGCs While, mechanically driven tribolayer during sliding enables oxidative wear and improved tribological properties in the Ti45Zr25Nb6Cu5Be17Sn2 BMGC. Based on the synergistic mechanical and chemical effects, the underlying relationship between the intrinsic dendrite properties and the wear behaviors of BMGC was revealed. (C) 2018 Elsevier B.V. All rights reserved.