摘要
TiAl/Ti2AlC composites were prepared by in-situ hot pressing of TilAl/C powders mixtures and sintered at different temperatures were investigated by X- ray diffraction ( XRD ) of samples. The reaction procedure of Ti-Al-C system could be divided into three stnges. Below 900℃ , Ti reacts with Al to form TiAl intermetallics ; above 900 ℃ , C reacts with remain Ti to form TiC triggered by the exothermal reaction of Ti and Al ; TiAl reacts with TiC to produce dense TiAl/Ti2AlC compasites.In the holding stage, ternary Ti2AlC develops to layered polycrystal and composites pyknosis in the meanwhile. The mechanism of synthesis and microstructure was especially discussed.
TiAl/Ti2AlC composites were prepared by in-situ hot pressing of TilAl/C powders mixtures and sintered at different temperatures were investigated by X- ray diffraction ( XRD ) of samples. The reaction procedure of Ti-Al-C system could be divided into three stnges. Below 900℃ , Ti reacts with Al to form TiAl intermetallics ; above 900 ℃ , C reacts with remain Ti to form TiC triggered by the exothermal reaction of Ti and Al ; TiAl reacts with TiC to produce dense TiAl/Ti2AlC compasites.In the holding stage, ternary Ti2AlC develops to layered polycrystal and composites pyknosis in the meanwhile. The mechanism of synthesis and microstructure was especially discussed.
基金
FundedbytheNationalNaturalScienceFoundationofChina(No.50572080)