Because of the difference in the coefficient of thermal expansion of Al alloy and SiC_p, the residual-stress generates during the process of fabricating Al alloy reinforced by SiC_p. The analyzing residual-stress quan...Because of the difference in the coefficient of thermal expansion of Al alloy and SiC_p, the residual-stress generates during the process of fabricating Al alloy reinforced by SiC_p. The analyzing residual-stress quantitatively by XRD shows that residual-stress is essential character of Al alloy reinforced by SiC_p, and the residual-stress in Al alloy matrix is tensile stress. The residual-stress decreases along with lessening of SiC_p size, which shows better microyield behavior. In annealing, the residual-stress of LY12+150#SiC_p is lower than that of ZL101+150#SiC, thus it has better microyield behavior. The residual-stress of solution-aging is bigger than that of annealing. The microyield behavior is also explained from the parameter change of microstructure to microyield behavior. Space-group relative microdistortion of Al alloy reinforced decreases along with lessening of SiC_p size, which has good microyield behavior.展开更多
Porous silicon film is a capillary-like medium, which is able to reveal different meso-elastic modulus with porosity. During the preparation of porous silicon samples, the capillary force is a non-classic force relate...Porous silicon film is a capillary-like medium, which is able to reveal different meso-elastic modulus with porosity. During the preparation of porous silicon samples, the capillary force is a non-classic force related to the liquid evaporation which directly influences the evolution of residual stress. In this study, a non-linear relation of Raman shift to stress coefficient and the porosity is obtained from the elastic modulus measured with nano-indentation by Bellet et al. [J. Appl. Phys. 60 （1996） 3772] Dynamic capillarity during the drying process of porous silicon is investigated using micro-Raman spectroscopy, and the results reveal that the residual stress resulted from the capillarity increased rapidly. Indeed, the dynamic capillarity has a close relationship with a great deal of micro-pore structures of the porous silicon.展开更多
文摘Because of the difference in the coefficient of thermal expansion of Al alloy and SiC_p, the residual-stress generates during the process of fabricating Al alloy reinforced by SiC_p. The analyzing residual-stress quantitatively by XRD shows that residual-stress is essential character of Al alloy reinforced by SiC_p, and the residual-stress in Al alloy matrix is tensile stress. The residual-stress decreases along with lessening of SiC_p size, which shows better microyield behavior. In annealing, the residual-stress of LY12+150#SiC_p is lower than that of ZL101+150#SiC, thus it has better microyield behavior. The residual-stress of solution-aging is bigger than that of annealing. The microyield behavior is also explained from the parameter change of microstructure to microyield behavior. Space-group relative microdistortion of Al alloy reinforced decreases along with lessening of SiC_p size, which has good microyield behavior.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10232030 and 10502014.
文摘Porous silicon film is a capillary-like medium, which is able to reveal different meso-elastic modulus with porosity. During the preparation of porous silicon samples, the capillary force is a non-classic force related to the liquid evaporation which directly influences the evolution of residual stress. In this study, a non-linear relation of Raman shift to stress coefficient and the porosity is obtained from the elastic modulus measured with nano-indentation by Bellet et al. [J. Appl. Phys. 60 （1996） 3772] Dynamic capillarity during the drying process of porous silicon is investigated using micro-Raman spectroscopy, and the results reveal that the residual stress resulted from the capillarity increased rapidly. Indeed, the dynamic capillarity has a close relationship with a great deal of micro-pore structures of the porous silicon.
