Miniature mechanical testing of LMD-fabricated compositionally & microstructurally graded γ titanium aluminides

Abstract The design freedom in Laser Metal Deposition provided by the absence of a powder bed enables fabrication Functionally Graded Materials through Additive Manufacturing. For first time, two suitable γ-TiAl alloys (TiAl48Cr2Nb2, TiAl45Nb4C) are combined direct and gradual transitions to generate different microstructure morphologies and, consequently, mechanical properties within component after an identical heat treatment. influence alloy composition, type, material transition on tensile fracture toughness is analyzed miniature testing. Miniature tests show no orientation dependency regard build direction composition/microstructure not found be preferred site. reveal that already small composition changes—insufficient alter configuration—can have significant effect cracking behavior. Graphical abstract