Study on the chemical stability of the synthesized TiCx in Ti-Al-C system after immersion in the HF?+?H2O2 solution

The aim of this study is to investigate the phase stability of the prepared TiC_x in Ti-Al-C system after immersion in the mixture of hydrofluoric acid (HF) and H₂O₂. The powders were immersed in the solution for different period times of 24, 48 and 96?h. The phase change of powders after different immersion times was studied by X-ray diffraction (XRD). The morphology evolution was detected by the field-emission scanning electron (FESEM). Moreover, atomic absorption spectroscopy (AAS) analysis was employed to study the changes in the chemical composition of solutions. The XRD results showed that by increasing the immersion time, gradually, the TiC_x decomposed. It was also found that the selection oxidation aluminum occurred and the Al₂O₃ was the main final product of treatments. The FESEM images also confirmed the XRD results and after immersion of the powders into the solutions the rod-like and sheet-like morphology of the Al₂O₃ particles were obtained.