Titanium aluminide (TiAl) alloys have emerged as promising materials for high-temperature applications due to their unique combination of strength, low density, and excellent oxidation resistance. However, the fabrication TiAl using conventional methods is challenging high melting points limited ductility. Selective laser (SLM), an additive manufacturing technique, offers a viable solution prod...

First-principles calculations based on a plane-wave pseudopotential method, as implemented in the VASP code, are presented for the formation energies of several transition-metal and non-transition-metal dopants in Ti–Al alloys. Substitution for either Ti or Al in g-TiAl, a2-Ti3Al, Ti2AlC, and Ti3AlC are considered. Calculated szero-temperatured defect formation energies exhibit clear trends as ...

Because of their inherent low ductility, TiAl-based materials are difficult to fabricate, especially thin gage titanium gamma aluminide (TiAl) sheet and foil. In this paper, an innovative powder metallurgy approach for producing cost-effective thin gage TiAl sheets (with 356 mm long and 235 mm wide, and a thickness of 0.74, 1.09, 1.55, and 2.34 mm, respectively) is presented. The microstructure...

TiAl-based alloys have been suggested as advanced high-temperature structural materials replacing the Ni-based superalloys, due to their low density, high modulus, good oxidation resistance and creep resistance. However, their poor ductility and toughness at low temperature limits their applications in industry. Generally, controlling the microstructure and alloying elements are the most useful...

A theoretical study of the structural, elastic, and mechanical properties of B19 TiAl intermetallic compound with orthorhombic structure has been carried out by using ab initio density functional theory calculations based on the projector augmented wave and the generalized gradient approximation. The optimized structure parameters are found to be in agreement with the available experimental dat...

In this work, plastic deformation was locally introduced at room temperature by nanoindentation on a γ-TiAl-based alloy. Comprehensive analyses of microstructures were performed before and after deformation. In particular, the Burgers vectors, the line directions, and the mechanical twinning systems were studied via accurate electron channeling contrast imaging. Accommodation of the deformation...

The microstructure evolution and interface characteristics of a directionally solidified Ti-43Al-3Si (at.%) alloy in an alumina (Al2O3) crucible with new Y2O3 skull-aided technology were investigated. The Y2O3-skull that is in contact with the TiAl-melt is relatively stable, which results in a more controlled reaction between the skull and the melt than in the case of an Al2O3 crucible is used....

TiAl₃ and TiN composite nanoparticles were continuously synthesized from Ti-48Al master alloy by hydrogen plasma-metal reaction in a N₂, H₂ and Ar atmosphere. The phase, morphology, and size of the nanoparticles were studied by X-ray diffraction (XRD) and transmission electronic microscopy (TEM). X-ray photoelectron spectroscopy (XPS) and evolved gas analysis (EGA) were used to analyze the surf...

Semiempirical interatomic potentials have been developed for Al, a-Ti, and g-TiAl within the embedded atom method ~EAM! formalism by fitting to a large database of experimental as well as ab initio data. The ab initio calculations were performed by the linearized augmented plane wave ~LAPW! method within the density functional theory to obtain the equations of state for a number of crystal stru...