Comparative study of the compression properties of TiAl matrix composites reinforced with nano-TiB2 and nano-Ti5Si3 particles

The TiAl matrix composites reinforced with nano-TiB2 and nano-Ti5Si3 particles were successfully fabricated by the in situ method of combustion synthesis and hot press consolidation. The sizes of the synthesized TiB2 and Ti5Si3 particles are about 30-50 nm and 60-80 nm, respectively. The synthesized nano-TiB2 particles could significantly enhance the ultimate compression strength (σtrueUCS) of the TiAl alloy, and the σtrueUCS increases with the increase in the TiB2 content. The average σtrueUCS of the 6 vol% TiB2/TiAl composite is 477 MPa higher than that of the TiAl alloy. The synthesized nano-Ti5Si3 particles could improve the strength and ductility of the TiAl alloy simultaneously, and the σtrueUCS and fracture strain (εtruef) increase first and then decrease with the increase in the Ti5Si3 content. The average σtrueUCS of the 4 vol% Ti5Si3/TiAl composite is 171 MPa higher than that of the TiAl alloy, and the average εtruef increases from 17.3% to 20.9%.