Self-toughening ZrB2–SiC based composites are fabricated by in-situ reactive hot pressing.The effect of sintering additive content on the microstructure and mechanical properties of the composites is investigated.Mic...Self-toughening ZrB2–SiC based composites are fabricated by in-situ reactive hot pressing.The effect of sintering additive content on the microstructure and mechanical properties of the composites is investigated.Microstructure observation found that the in-situ reactive hot pressing could promote the anisotropic growth of ZrB2 grains and the formation of interlocking microstructure.Such microstructure could improve the mechanical properties,especially,for the fracture toughness.The improved mechanical properties could be attributed to the self-toughening structure related to the ZrB2 platelets and the formed interlocking microstructure,which could trigger various toughening mechanisms such as grain pull-out,crack bridging,crack deflection,and crack branching,providing the main contribution to the high fracture toughness.展开更多
基金supported by research fund for the China Postdoctoral Science Foundation(2016M600201,2018T110214,2016M601304)National Natural Science Foundation of China(51805069)+1 种基金Natural Science Foundation of Liaoning Province,China(20170540154)Aviation Science Foundation of China(2016ZF63007).
文摘Self-toughening ZrB2–SiC based composites are fabricated by in-situ reactive hot pressing.The effect of sintering additive content on the microstructure and mechanical properties of the composites is investigated.Microstructure observation found that the in-situ reactive hot pressing could promote the anisotropic growth of ZrB2 grains and the formation of interlocking microstructure.Such microstructure could improve the mechanical properties,especially,for the fracture toughness.The improved mechanical properties could be attributed to the self-toughening structure related to the ZrB2 platelets and the formed interlocking microstructure,which could trigger various toughening mechanisms such as grain pull-out,crack bridging,crack deflection,and crack branching,providing the main contribution to the high fracture toughness.
