In this work, the kinetics of intermetallic compounds formation in Ti/Al system was studied by immersing titanium plates in molten aluminum at 750 ºC, 850 ºC and 950 ºC. According to Scanning Electron Microscopy and X-Ray Diffraction Analysis results TiAl3 is the only phase which forms in different temperatures. At 750 ºC, thickness of TiAl3 layer increases slowly to 20 μm. After 3 hours, TiAl3 thickness quickly increases to about 500 μm. Presumably reaction starts with solving titanium in molten aluminum and then TiAl3 layer forms. Different molar volume of Ti and TiAl3 causes in tensile stresses in the Ti-TiAl3 interface which leads to TiAl3 layer disruption. This disrupted layer causes molten aluminum to be in contact again with titanium surface and therefore TiAl3 thickness starts to increase significantly. Also activation energy of intermetallic layer formation and growth was calculated by measuring Ti thickness decrease by time. Calculated activation energy is 110.8 kJ/mol which roughly equals to sum of activation energies of TiAl3 formation and aluminum diffusion through the TiAl3 layer.

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