TiB whiskers reinforced high temperature titanium Ti60 alloy composites with novel network microstructure

摘要

TiB whiskers reinforced high temperature titanium Ti60 alloy (TiBw/Ti60) composites with a novel network microstructure have been successfully fabricated by the system of large spherical Ti60 powders and fine TiB_2 powders. The results show that the minimum temperature fabricating the composites by reaction hot pressing (RHP) is established to be 1300℃ due to usage of high temperature titanium Ti60 alloy. The TiB whiskers are in situ synthesized around large Ti60 matrix particles and then formed a novel three-dimensional (3D) network microstructure. The tensile strength of 8 vol.% TiBw/Ti60 composites with a network microstructure is increased by 61.1%, 57.4% and 45.5% compared with that of the monolithic Ti60 alloy at 600 °C, 700 °C and 800 °C, respectively. The superior improvement can be mainly attributed to the network microstructure, grain refinement and usage of large spherical Ti60 powders.