CaSO 4 whisker reinforcing and toughening mechanisms for polyurethane elastomer were studied. The effects of dispersity of CaSO 4 whisker and interfacial bonding state on reinforcement and toughness were discussed.T...CaSO 4 whisker reinforcing and toughening mechanisms for polyurethane elastomer were studied. The effects of dispersity of CaSO 4 whisker and interfacial bonding state on reinforcement and toughness were discussed.The microanalyses showed that CaSO 4 whisker reinforcing mechanism for polyurethane elastomer mainly was load transferring and its toughening mechanism involved crack deflection and whisker pullout.The results indicated that composites with 5%-10% CaSO 4 whisker exhibited the best mechanical properties. Good bonding interface was formed between whisker and matrix after the surface of CaSO 4 whisker was treated by silane coupling agent.The fairly improved strength and toughness are attributed to the better interfacial bonding state.展开更多
Mixed rare earth elements were incorporated into alumina ceramic materials. Hot-pressing was used to fabricate alumina matrix composites in nitrogen atmosphere protection. Microstructures and mechanical properties of ...Mixed rare earth elements were incorporated into alumina ceramic materials. Hot-pressing was used to fabricate alumina matrix composites in nitrogen atmosphere protection. Microstructures and mechanical properties of the composites were tested. It was indicated that the bending strength and fracture toughness of alumina matrix ceramic composites sintered at 1550 ℃ and 28 MPa for 30 min were improved evidently. Besides mixed rare earth elements acting as a toughening phase, AlTiC master alloys were also added in as sintering assistants, which could prompt the formation of transient liquid phase, and thus nitrides of rare earth elements were produced. All of the above were beneficial for improving the mechanical properties of alumina matrix ceramic composites.展开更多
Mixed rare earth elements were incorporated into alumina ceramic materials. Hot-pressing was used to fabricate alumina matrix composites with nitrogen atmosphere protection. Microstructures and mechanical properties o...Mixed rare earth elements were incorporated into alumina ceramic materials. Hot-pressing was used to fabricate alumina matrix composites with nitrogen atmosphere protection. Microstructures and mechanical properties of the composites were tested. It is indicates that the bending strength and fracture toughness of alumina matrix ceramic composites sintered at 1550℃ and 28 MPa for 30 min are improved evidently. Based on mixed rare earth elements acting as a toughening phase, AlTiC master alloys were also added in as sintering assistant, which could prompt the formation of transient liquid phase, and thus nitrides of rare earth elements were produced. All the above are beneficial to the improvement of mechanical properties of alumina matrix ceramic composites.展开更多
基金FundedbytheNaturalScienceFoundationofShanxiProvince (No .9910 2 4 )
文摘CaSO 4 whisker reinforcing and toughening mechanisms for polyurethane elastomer were studied. The effects of dispersity of CaSO 4 whisker and interfacial bonding state on reinforcement and toughness were discussed.The microanalyses showed that CaSO 4 whisker reinforcing mechanism for polyurethane elastomer mainly was load transferring and its toughening mechanism involved crack deflection and whisker pullout.The results indicated that composites with 5%-10% CaSO 4 whisker exhibited the best mechanical properties. Good bonding interface was formed between whisker and matrix after the surface of CaSO 4 whisker was treated by silane coupling agent.The fairly improved strength and toughness are attributed to the better interfacial bonding state.
基金the Outstanding Young Scientist Rewards of Shandong Province (05BS04008)the Natural Science Fund of Shandong Province (Y2007F29)
文摘Mixed rare earth elements were incorporated into alumina ceramic materials. Hot-pressing was used to fabricate alumina matrix composites in nitrogen atmosphere protection. Microstructures and mechanical properties of the composites were tested. It was indicated that the bending strength and fracture toughness of alumina matrix ceramic composites sintered at 1550 ℃ and 28 MPa for 30 min were improved evidently. Besides mixed rare earth elements acting as a toughening phase, AlTiC master alloys were also added in as sintering assistants, which could prompt the formation of transient liquid phase, and thus nitrides of rare earth elements were produced. All of the above were beneficial for improving the mechanical properties of alumina matrix ceramic composites.
文摘Mixed rare earth elements were incorporated into alumina ceramic materials. Hot-pressing was used to fabricate alumina matrix composites with nitrogen atmosphere protection. Microstructures and mechanical properties of the composites were tested. It is indicates that the bending strength and fracture toughness of alumina matrix ceramic composites sintered at 1550℃ and 28 MPa for 30 min are improved evidently. Based on mixed rare earth elements acting as a toughening phase, AlTiC master alloys were also added in as sintering assistant, which could prompt the formation of transient liquid phase, and thus nitrides of rare earth elements were produced. All the above are beneficial to the improvement of mechanical properties of alumina matrix ceramic composites.