Grain refinement through borides is known to be suppressed when TiAl welded with a laser beam. As β grains do not primarily nucleate on boride at high cooling rate, mixture of nitrogen and argon applied as protecting gas for the formation TiN during solidification. The phase transformation changed correspondingly from Liquid → + α γ+ α2 γ B2 β+ TiN. It found that prefer heterogeneously suspendi...

The alloying elements Nb, Ta and Zr improve the creep properties of fully lamellar γ/α2 titanium aluminides significantly. Since high temperature deformation mainly occurs in γ-phase aluminides, diffusivity solid solution hardening effect these three is studied by analyzing concentration gradients resulting hardness across interdiffusion zone diffusion couples energy dispersive X-ray diffractio...

in this research, aluminizing packs containing naf and nh4cl activators were used for aluminizing of pure titanium samples at 1100 ºc. the results showed that the layers of tial3, tial2, γ-tial, α2-ti3al, and α-solid solution are formed on titanium samples in both cases. however, the weight gain and the thickness of tial3 layer in treated samples with nh4cl activator are greater than those when...

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...

Paduan intermetalik TiAl telah banyak mencuri perhatian industri transportasi terutama pesawat terbang karena memiliki densitas yang jauh lebih rendah daripada paduan super berbasis nikel dan kekuatan baik pada temperatur tinggi. Penggunaan secara luas masih terbatas keuletan ketangguhan kamar, sehingga penambahan elemen pemadu dapat menjadi solusi peningkatan sifat mekanis paduan. Peningkatan ...

in this research, the high-energy planetary mill was employed to produce nanocrystalline ti-50al(γ)(at%) powders. initial powders were mechanically alloyed in 99.9999% and 90% purities of argon and also air atmosphere with alloying times up to 50h. the effect of impurity of argon atmosphere on the microstructure and the rate of phase transformation of ti-50al were investigated during mechanical...

The microstructure and tensile properties of β-containing Ti–44Al–4Cr alloy rods additively manufactured by electron beam melting (EBM) process were examined as a function input energy density determined the processing parameters. To best our knowledge, this is first report to demonstrate that two types fine microstructures have been obtained in γ-TiAl alloys varying during EBM process. A unifo...