[16P-T14-09] High-temperature Rheological Behavior and Microstructure Evolution of Mo-12Si-8.5B alloy Reinforced by Layered Mo2TiAlC2 Phase
Keywords:Mo-Si-B alloy, Mo2TiAlC2 phase, Hot deformation, Microstructure evolution
The rheological behavior of Mo-12Si-8.5B alloy reinforced by a layered Mo2-TiAlC2 phase has been studied at temperatures ranging from 1200℃ to1400℃ with different strain rate. The flow stress and microstructure evolution were investigated. The results indicated that the Mo2TiAlC2 strengthens the Mo-12Si-8.5B alloy mainly by particle strengthening and grain boundary strengthening at high temperatures. With the increase of Mo2TiAlC2 content, the peak stress of the alloys improved. As the temperature increases or strain rate decreases, the peak stress of the alloys decreases significantly. The microstructure reveals that the deformation of the Mo-12Si-8.5B-Mo2TiAlC2 alloy at high temperatures is mainly provided by the deformation of the α-Mo phase and grain boundary sliding. As the temperature rises to 1300–1400℃, the intermetallic phase gradually participates in the deforming but contributes less to the total deformation. Dynamic recovery and recrystallization greatly reduce dislocations at high temperatures. The Mo2TiAlC2 particles can inhibit recrystallization grain growth.