FAST-forge and structural integrity of demonstrator near net shape components produced from dissimilar titanium alloy powdersThursday (07.11.2019) 09:35 - 09:55 Part of:
Titanium alloys are used extensively in the aerospace sector due to the good combination of high strength-to-weight ratio and corrosion resistance. Many of the aerospace components are exposed to extreme service stress states and temperatures, which in some applications requires overengineering to avoid compromising the components performance when a single alloy is used. This will add more weight and it will make the final design less efficient. A potential solution to this issue could be the combination of dissimilar titanium alloys in subcomponent regions, achieved through diffusion bonding of powders via field assisted sintering technology (FAST-DB) and subsequent hot forging (FAST-forge). Such an approach will provide designers with a new hybrid process for producing near net shape titanium alloy components with forged properties.
In this project, near net shape titanium alloy demonstrator components are produced from oversized AM powders in just two solid-state steps; FAST-DB and hot forging. Three large FAST-DB disks have been fully consolidated at temperatures above and below the respective beta transus temperatures of alloys Ti-6Al-4V and Ti-6Al-2Sn-4Zr-2Mo. One FAST-DB disk sintered below the beta transus has been machined into pre-forge billets and then hot closed-die forged. A range of static and dynamic mechanical testing has been carried out to assess the structural integrity of the bonds. The microstructure and property evolution of the forged demonstrator components will be presented.