Th goal of the pr s nt p r is to obt in some differ tial sub rdin tion an sup dination rems for univalent functions related b differential operator Also, we discussed sandwich-type results.

In the present work, γ-TiAl-based alloys with nominal composition of Ti-48Al-2Cr-2Nb (at.%) were prepared by vacuum hot pressing sintering using pre-alloyed powders under different pressures. The oxidized cyclic conditions at 900 °C in air for up to 100 h. effects surface defects on morphology oxide scale investigated. It was found that increased porosities had mass gains after oxidation as a r...

Advanced intermetallic alloys based on the γ-TiAl phase have become widely regarded as most promising candidates to replace heavier Ni-base superalloys as materials for high-temperature structural components, due to their facilitating properties of high creep and oxidation resistance in combination with a low density. Particularly, recently developed alloying concepts based on a β-solidificatio...

One of the principal problems with nano-crystalline materials is producing them in quantities and sizes large enough for valid mechanical property evaluation. The purpose of this study was to explore an innovative method for producing nano-crystalline γ-TiAl bulk materials using high energy ball milling and brief secondary processes. Nano-crystalline powder feedstock was produced using a Fritsc...

Dissimilar metal samples of TC4/TiAl were successfully prepared by laser additive manufacturing (LAM) technology, with pure vanadium as the interlayer. The microstructure, phase composition, element distribution and mechanical properties at interface TC4/V TiAl/V analyzed optical microscope (OM), scanning electron (SEM) backscattering diffraction (EBSD). experimental results showed that microst...

Due to TiAl alloys’ excellent properties, alloys have received widespread attention from researchers. However, the high energy consumption and lengthy process of traditional preparation methods always limited large-scale application alloys. This article develops a new method for preparing TiAl-based alloy powder via magnesium thermal reduction TiO2 in AlCl3-KCl molten salt. In this study, propo...

The solidification of gamma TiAl alloys is of interest to the aerospace and automotive industries. A gamma TiAl multicomponent alloy: Ti–45.5Al–4.7Nb–0.2C–0.2B (at. %) has been the focus of a study to investigate the solidification conditions that led to a Columnar to Equiaxed Transition (CET) in a directional solidification experiment where traditional Bridgman solidification was combined in s...

The effects of pressure on the structural and elastic properties of orthorhombic TiAl are investigated using first-principles calculations based on density functional theory within the projector augmented wave method. The calculated lattice parameters at 0 GPa are in good agreement with the available experimental data. The pressure dependence of the normalized lattice parameters and the single ...

Neutron diffraction has been used for in-situ investigations to elucidate the phase transformation behavior of two Mo-containing TiAl alloys with compositions of Ti-44Al3Mo and Ti-44Al-7Mo (in at.%). Five different phases are present in these alloys. These include three ordered phases at room temperature, namely a2, b0 and c and two disordered phases, a and b, which occur at higher temperatures...