FRACTURE-TOUGHNESS AND MICROSTRUCTURE IN TIB PARTICULATE-REINFORCED TI-6AL-2SN-4ZR-2MO COMPOSITES

Fracture characteristics and fracture mechanism of TIE particulate-rei nforced Ti-6Al-2Sn-4Zr-2Mo composites with various volume fraction of RE particles fabricated by blended elemental method were investigated by carrying gut static and dynamic fracture toughness tests. Both stat ic and dynamic fracture toughness values decrease with increasing the volume fraction of TiB particles. The dynamic fracture toughness value is fairly smaller than the static fracture toughness value. The ratio of dynamic fracture toughness Value to Static fracture toughness valu e increases as the volume fraction of TIE particles increases. The fra cture toughness values increases with increasing the degree of crack d eflection which is greater under static conditions than under dynamic conditions. The fraction of TiB particles on the fracture surface is g reater in the specimen with greater volume fraction of TiB particles, and is greater under dynamic conditions than under static conditions.