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Ti–Al surface alloy was fabricated using a cyclic pulsed liquid-phase mixing of predeposited 100 nm Al film with a-Ti substrate by low-energy high-current electron beam. Electron probe micro-analysis(EPMA),grazing incidence X-ray diffraction analysis(GIXRD),transmission electron microscopy(TEM), and nanoindentation were used to investigate the characterization of Ti–Al surface alloy. The experimental results show that the thickness of alloy layer is *3 lm, and the content of Al in the *1 lm thickness surface layer is *60 at%. The tetragonal TiAl and TiAl2intermetallics were synthesized at the top surface, which have nanocrystalline structure.The main phase formed in the *2.5 lm thick surface is TiAl, and there are few TiAl2and Ti3Al phase for the alloy.Dislocation is enhanced in the alloyed layer. The nanohardness of Ti–Al surface alloy increased significantly compared with a-Ti substrate due to the nanostructure and enhanced dislocation. Since the e-beam remelted repeatedly, the Ti–Al surface alloy mixed sufficiently with Ti substrate. Moreover, there is no obvious boundary between the alloyed layer and substrate.
Ti-Al surface alloy was fabricated using a cyclic pulsed liquid-phase mixing of predeposited 100 nm Al film with a-Ti substrate by low-energy high-current electron beam. Electron probe micro-analysis (EPMA) diffraction analysis (GIXRD), transmission electron microscopy (TEM), and nanoindentation were used to investigate the characterization of Ti-Al surface alloy. The experimental results show that the thickness of alloy layer is * 3 lm, and the content of Al in the * 1 lm thickness surface layer is * 60 at%. The tetragonal TiAl and TiAl2intermetallics were synthesized at the top surface, which have nanocrystalline structure. The main phase formed in the * 2.5 lm thick surface is TiAl, and there are few TiAl2and Ti3Al phase for the alloy. Dislocation is enhanced in the alloyed layer. The nanohardness of Ti-Al surface alloy increased significantly compared with a-Ti substrate due to the nanostructure and enhanced dislocation. Since the e-beam remelted repeatedly, the Ti-Al surface alloy mixed sufficiently with Ti substrate. There, there is no obvious boundary between the alloyed layer and substrate.