Investigation of Silver Synthesis to Reduce Friction and Wear of TiAl-Based Composites

Abstract

The urgency of development in the aviation industry has motivated further optimization of TiAl alloys with respect to friction and wear. In this paper, dendritic silver has been prepared to improve the behavior under friction and wear of TiAl-10 wt.%Ag (TA10A) printed via selective laser melting (SLM). Associated properties were examined using a ball-on-disk tribometer. A friction coefficient of 0.28 and wear rate of 1.51 × 10−4 mm3 N−1 m−1 were observed at 450 °C, both of which were lower than the values obtained at other temperatures. The relatively higher expansion coefficient at 450 °C was beneficial to the extraction of silver from TA10A, which accelerated the enrichment of silver on wear scar. Low tensile strength of silver makes it amenable to significant plastic deformation, and as a result, it can spread out easily over wear scars, and increase its area of distribution to form a silver-rich lubrication layer. The high plastic ductility of silver induced the lubrication layer to be well maintained during wear, resulting in a low friction coefficient and wear rate.