Microstructure and mechanical properties of TiAl alloys produced by rapid heating and open die forging of blended elemental powder compacts

Abstract

Ti-43Al-5V-4Nb (at%) intermetallic compounds were fabricated by a rapid heating and open die forging method using blended elemental powders. The process route consisted of powder blending, compacting, rapid heating, open die forging and heat treatment. During heating there is porosity in the blended and warm compacted powder billets which still persists after the first forging. In order to remove this difficulty a two stage forging process was used. A fully lamellar structure was seen in the TiAl alloy after heat treatment. Overall, the TiAl alloy showed moderately good mechanical properties at room temperature and good mechanical properties, with reasonable strength and good ductility at high temperatures.