Papers by Author: Jonathan D.H. Paul

Abstract: β solidifying γ titanium aluminide alloys exhibit fine and homogeneous microstructures in the cast condition, in particular if the alloys contain B as a grain refining agent. Following work in the literature [1], it is demonstrated that the grain refining effect due to B is solely attributed in such alloys to its effect on the solid-state β/α transformation. The results further show that grain refinement in these materials can be obtained by a simple heat treatment, even if the microstructure has been extensively coarsened through prior heat-treatment.

Abstract: The processing of large or near-net shaped parts from g-TiAl alloys is extremely challenging. The forging of large-scale TiAl-parts is hampered by the unavailability of high-quality, chemical homogenous pre-material. However, using an innovative combination of forging and joining large discs of TiAl with excellent mechanical properties can be produced. Metal Injection Moulding (MIM) facilitates the production of near-net shaped parts of high-strength TiAl-alloys with strength comparable to the cast condition.