摘要
Two intermetallic compounds of Ti-50at.%Al and Ti-48at.%Al-2at.%Cr were prepared with a mechanical alloying and pulse discharge sintering process. The as-sintered material shows a microstructure of equiaxed gamma grain with sub-micron size. Heat treatments in Vacuum at different temperatures up to 1573 K were conducted on the sintered materials. The microstructure of the material coarsened considerably after heat treatment at temperatures higher than 1523 K. The mechanical properties of the as-sintered and the heat treated materials were measured at temperatures up to 973 K, with four-point bending tests. Experimental results indicate that the addition of Cr increases the fracture strength of the intermetallic compound at room temperature and at elevated temperatures as well. The bending fracture strength increases with increasing testing temperature up to about 873 K and a decrease following up. Both fracture strength and fracture strain of the material were found to be improved by heat treatment. (Edited author abstract) 10 Refs.
Two intermetallic compounds of Ti-50at.%Al and Ti-48at.%Al-2at.%Cr were prepared with a mechanical alloying and pulse discharge sintering process. The as-sintered material shows a microstructure of equiaxed gamma grain with sub-micron size. Heat treatments in Vacuum at different temperatures up to 1573 K were conducted on the sintered materials. The microstructure of the material coarsened considerably after heat treatment at temperatures higher than 1523 K. The mechanical properties of the as-sintered and the heat treated materials were measured at temperatures up to 973 K, with four-point bending tests. Experimental results indicate that the addition of Cr increases the fracture strength of the intermetallic compound at room temperature and at elevated temperatures as well. The bending fracture strength increases with increasing testing temperature up to about 873 K and a decrease following up. Both fracture strength and fracture strain of the material were found to be improved by heat treatment. (Edited author abstract) 10 Refs.
