Taking a Ti−5Al−5Mo−5V−1Cr−1Fe alloy as exemplary case,the fatigue crack growth sensitivity and fracture features with various tailoredαphase morphologies were thoroughly investigated using fatigue crack growth rate(...Taking a Ti−5Al−5Mo−5V−1Cr−1Fe alloy as exemplary case,the fatigue crack growth sensitivity and fracture features with various tailoredαphase morphologies were thoroughly investigated using fatigue crack growth rate(FCGR)test,optical microscopy(OM)and scanning electron microscopy(SEM).The tailored microstructures by heat treatments include the fine and coarse secondaryαphase,as well as the widmanstatten and basket weave features.The sample with coarse secondaryαphase exhibits better comprehensive properties of good crack propagation resistance(with long Paris regime ranging from 15 to 60 MPa·m1/2),high yield strength(1113 MPa)and ultimate strength(1150 MPa),and good elongation(11.6%).The good crack propagation resistance can be attributed to crack deflection,long secondary crack,and tortuous crack path induced by coarse secondaryαphase.展开更多
The influence of grain structure and Ce on the strength ductility combination for aluminum lithium alloy was investigated. The strength ductility combination of pancake shape unrecrystallized grains is superior to...The influence of grain structure and Ce on the strength ductility combination for aluminum lithium alloy was investigated. The strength ductility combination of pancake shape unrecrystallized grains is superior to that of recrystallized grains. A significant improvement in strength ductility combination can be achieved by adding Ce to alloy 2090. According to the research results about fracture and properties of monotonic tension for Al Li alloys 2090 and 2090+Ce, the relationship among grain structure, strength differences between grain within and grain boundary, stress localization degree at grain boundary and extrinsic strengthening effect was researched. The method and mechanisms of optimizing strength ductility were discussed, including grain structure, subgrain, T 1 phase, rare earth element Ce and aging procedure.展开更多
The effect of electric field on the mechanical properties and microstructure of AI-Li alloy containing Ce was investigated, and mechanism was discussed. The experimental results show that the ductility of the alloy is...The effect of electric field on the mechanical properties and microstructure of AI-Li alloy containing Ce was investigated, and mechanism was discussed. The experimental results show that the ductility of the alloy is enhanced by the electric field. The fracture features are changed and the precipitates are dispersed under the effect of the electric field. The mechanism discussion reveals that the effects of the electric field on the alloy are due to the change of the electron density in the alloy.展开更多
基金Project(U1867201)supported by the National Natural Science Foundation of ChinaProject supported by State Key Laboratory of Powder Metallurgy,Central South University,China。
文摘Taking a Ti−5Al−5Mo−5V−1Cr−1Fe alloy as exemplary case,the fatigue crack growth sensitivity and fracture features with various tailoredαphase morphologies were thoroughly investigated using fatigue crack growth rate(FCGR)test,optical microscopy(OM)and scanning electron microscopy(SEM).The tailored microstructures by heat treatments include the fine and coarse secondaryαphase,as well as the widmanstatten and basket weave features.The sample with coarse secondaryαphase exhibits better comprehensive properties of good crack propagation resistance(with long Paris regime ranging from 15 to 60 MPa·m1/2),high yield strength(1113 MPa)and ultimate strength(1150 MPa),and good elongation(11.6%).The good crack propagation resistance can be attributed to crack deflection,long secondary crack,and tortuous crack path induced by coarse secondaryαphase.
文摘The influence of grain structure and Ce on the strength ductility combination for aluminum lithium alloy was investigated. The strength ductility combination of pancake shape unrecrystallized grains is superior to that of recrystallized grains. A significant improvement in strength ductility combination can be achieved by adding Ce to alloy 2090. According to the research results about fracture and properties of monotonic tension for Al Li alloys 2090 and 2090+Ce, the relationship among grain structure, strength differences between grain within and grain boundary, stress localization degree at grain boundary and extrinsic strengthening effect was researched. The method and mechanisms of optimizing strength ductility were discussed, including grain structure, subgrain, T 1 phase, rare earth element Ce and aging procedure.
文摘The effect of electric field on the mechanical properties and microstructure of AI-Li alloy containing Ce was investigated, and mechanism was discussed. The experimental results show that the ductility of the alloy is enhanced by the electric field. The fracture features are changed and the precipitates are dispersed under the effect of the electric field. The mechanism discussion reveals that the effects of the electric field on the alloy are due to the change of the electron density in the alloy.
