Preparation of Ti_3AlC_2 by mechanically activated sintering of 3Ti/Al/2C/0.2Sn

摘要

The mechanically activated sintering process was adapted to synthesize titanium aluminum carbide (Ti_3AlC_2) at low temperature. A mechanically induced self-propagation reaction occurred by mechanical alloying of 3Ti/Al/2C powder mixtures. In addition to powder products, a large amount of rigor granules with a size of 0.5 ～ 10 mm were produced. Fine powders containing Ti_3AlC_2, Ti_2AlC and TiC were obtained. The granules composed of Ti_3AlC_2, Ti_2AlC and TiC. Adding Sn may remove Ti_2AlC and enhance the synthesis of Ti_3AlC_2. After Sn was added, the products only contained Ti_3AlC_2 and TiC. The Ti_3AlC_2 content of the powders and granules were 75 wt% and 88 wt%, respectively. The mechanically alloyed products were pressureless sintered at 900-1300°C for 2 h. Sintering of these products at 900 ~ 1200°C yields samples containing over 95 wt% Ti_3AlC_2. The sintered powder compacts with high purity Ti_3AlC_2 had a fine organization. The lath Ti_3AlC_2 of the granules had a length of 10-20 μm.