Mg matrix composites with SiC particles ranging from 5vol%-25vol% were prepared using stirring casting method. Die casting, squeezing casting, and extrusion were applied for inhibiting or eliminating the defects such ...Mg matrix composites with SiC particles ranging from 5vol%-25vol% were prepared using stirring casting method. Die casting, squeezing casting, and extrusion were applied for inhibiting or eliminating the defects such as gas porosity and shrinkage void. Through die casting and squeezing casting, most of the defects in Mg matrix composites could be eliminated, but the mechanical properties were improved limitedly. On the other hand, after hot extrusion, not only most of the defects of as-cast composites ingots were eliminated, but also the mechanical properties were improved markedly. With the addition of SiC, the tensile strength, yield strength and elastic modulus of as extrusion SiCp/AZ61 composites increased remarkably, and the elongation decreased obviously.展开更多
Limited by serious heterogeneity both horizontally and vertically, water driving of low-permeability layers in Qiaokou oilfield appears to be very difficult. As the classⅠ layer reaches the stage of high water-conten...Limited by serious heterogeneity both horizontally and vertically, water driving of low-permeability layers in Qiaokou oilfield appears to be very difficult. As the classⅠ layer reaches the stage of high water-content too early, the level of exploitation became worse with low-recovery. Regarding the serious heterogeneity and low recovery in layers class Ⅱand Ⅲ, composite fracturing technology suitable for this kind of reservoir was applied. Its basement was a lab study of indoor water driving efficiency and fracturing experiment. Perfect result has achieved by using the technology.展开更多
The application of mechanical and chemical syntheses in an high-energy vibration mill of the FESTU makes easy the process of the introduction of reinforced powders in castle composite materials on the Al basis. The ob...The application of mechanical and chemical syntheses in an high-energy vibration mill of the FESTU makes easy the process of the introduction of reinforced powders in castle composite materials on the Al basis. The obtained reinforced phases of Al-Ti-C composition have high specific Surface due to peculiarities of explosive mechanical and chemical syntheses. It increases the uniformity of their distribution in a matrix melt during the mixing process and also increases properties of castle composite materials.展开更多
基金Funded by the Program for New Century Excellent Talents in University(NCET-12-1040)the National Natural Science Foundation of China(Nos.50901048 and 51174143)+2 种基金the Key Project of Chinese Ministry of Education(No.2012017)the Program Foundation of Ministry of Education of China(No.20101402110008)Natural Science Foundation of Shanxi(No.2010021022-5)
文摘Mg matrix composites with SiC particles ranging from 5vol%-25vol% were prepared using stirring casting method. Die casting, squeezing casting, and extrusion were applied for inhibiting or eliminating the defects such as gas porosity and shrinkage void. Through die casting and squeezing casting, most of the defects in Mg matrix composites could be eliminated, but the mechanical properties were improved limitedly. On the other hand, after hot extrusion, not only most of the defects of as-cast composites ingots were eliminated, but also the mechanical properties were improved markedly. With the addition of SiC, the tensile strength, yield strength and elastic modulus of as extrusion SiCp/AZ61 composites increased remarkably, and the elongation decreased obviously.
文摘Limited by serious heterogeneity both horizontally and vertically, water driving of low-permeability layers in Qiaokou oilfield appears to be very difficult. As the classⅠ layer reaches the stage of high water-content too early, the level of exploitation became worse with low-recovery. Regarding the serious heterogeneity and low recovery in layers class Ⅱand Ⅲ, composite fracturing technology suitable for this kind of reservoir was applied. Its basement was a lab study of indoor water driving efficiency and fracturing experiment. Perfect result has achieved by using the technology.
文摘The application of mechanical and chemical syntheses in an high-energy vibration mill of the FESTU makes easy the process of the introduction of reinforced powders in castle composite materials on the Al basis. The obtained reinforced phases of Al-Ti-C composition have high specific Surface due to peculiarities of explosive mechanical and chemical syntheses. It increases the uniformity of their distribution in a matrix melt during the mixing process and also increases properties of castle composite materials.
