G. Welsch, Case Western Reserve University, Cleveland, OH; J. Hausmann, K. Baumann, S. Lenser, K. Kelm, L. Chernova, K. Weber, S. Reh, Deutsches Zentrum für Luft- und Raumfahrt, Inst, Köln, Germany; W. Smarsly, MTU Aero Engines, München, Germany
An objective of processing is to shape the microstructure of a structural material to enable its performance in a finished product, e.g., by providing high strength, stiffness, and reliability. Microstructures that exhibit these properties can be formed in (α/β) as well as in (α2/γ) titanium alloys through methods which effect high degrees of refinement in composition and microstructure. The refinements concern (1) alloy homogeneity and uniformity, (2) grain- and colony size, (3) volume fraction and distribution of phases, (4) lattice misfit at phase boundaries, (5) texture, (6) residual stress, and (7) crystal defects that comprise mobile dislocations. Processing strategies are proposed for exemplar (α/β)-Ti-6Al-4V and (α2/γ)-Ti-Al alloys.
Summary: An objective of processing is to shape the microstructure of a structural material to enable its performance in a finished product, e.g., by providing high strength, stiffness, and reliability. Microstructures that exhibit these properties can be formed in (á/â) as well as in (á2/ã) titanium alloys through methods which effect high degrees of refinement in composition and microstructure. The refinements concern (1) alloy homogeneity and uniformity, (2) grain- and colony size, (3) volume fraction and distribution of phases, (4) lattice misfit at phase boundaries, (5) texture, (6) residual stress, and (7) crystal defects that comprise mobile dislocations. Processing strategies are proposed for exemplar (á/â)-Ti-6Al-4V and (á2/ã)-Ti-Al alloys.
