研究了蠕变温度与蠕变应力载荷对SiCp/Al复合材料高温蠕变行为的影响,分析了该复合材料的蠕变断裂机制,并计算得出了材料的应力指数与激活能。结果表明:蠕变速率随蠕变应力荷载的增大和蠕变温度的升高而增大,应力指数与变形激活能分别为...研究了蠕变温度与蠕变应力载荷对SiCp/Al复合材料高温蠕变行为的影响,分析了该复合材料的蠕变断裂机制,并计算得出了材料的应力指数与激活能。结果表明:蠕变速率随蠕变应力荷载的增大和蠕变温度的升高而增大,应力指数与变形激活能分别为n=9.8和Q=182 k J/mol。该复合材料的蠕变断裂机制为韧性断裂。通过对比得出,SiCp/Al复合材料的抗高温蠕变性能明显优于基体材料。展开更多
Potential links between the Arctic sea-ice concentration anomalies and extreme precipitation in China are explored. Associations behind these links can be explained by physical interpretations aided by visualisations ...Potential links between the Arctic sea-ice concentration anomalies and extreme precipitation in China are explored. Associations behind these links can be explained by physical interpretations aided by visualisations of temporarily lagged composites of variables such as atmospheric mean sea level pressure and sea surface temperature. This relatively simple approach is verified by collectively examining already known links between the Arctic sea ice and rainfall in China. For example, similarities in the extreme summer rainfall response to Arctic sea-ice concentration anomalies either in winter （DJF） or in spring （MAM） are highlighted. Furthermore, new links between the Arctic sea ice and the extreme weather in India and Eurasia are proposed. The methodology developed in this study can be further applied to identify other remote impacts of the Arctic sea ice variability.展开更多
The influence of solid solution treatments on the dissolution of carbides precipitates,the grain size,and the hardness of high strength low expansion alloy were investigated through XRD analysis,microstructure observa...The influence of solid solution treatments on the dissolution of carbides precipitates,the grain size,and the hardness of high strength low expansion alloy were investigated through XRD analysis,microstructure observations,and theoretical computation.It was seen that most primary Mo2C type carbide band dissolved in a temperature range of 1 100-1 150 ℃.When the temperature was over 1 200 ℃,the grain size increased remarkably,which led to the reduction of hardness.展开更多
文摘研究了蠕变温度与蠕变应力载荷对SiCp/Al复合材料高温蠕变行为的影响,分析了该复合材料的蠕变断裂机制,并计算得出了材料的应力指数与激活能。结果表明:蠕变速率随蠕变应力荷载的增大和蠕变温度的升高而增大,应力指数与变形激活能分别为n=9.8和Q=182 k J/mol。该复合材料的蠕变断裂机制为韧性断裂。通过对比得出,SiCp/Al复合材料的抗高温蠕变性能明显优于基体材料。
基金supported by the Academy of Finland (contract 259537)
文摘Potential links between the Arctic sea-ice concentration anomalies and extreme precipitation in China are explored. Associations behind these links can be explained by physical interpretations aided by visualisations of temporarily lagged composites of variables such as atmospheric mean sea level pressure and sea surface temperature. This relatively simple approach is verified by collectively examining already known links between the Arctic sea ice and rainfall in China. For example, similarities in the extreme summer rainfall response to Arctic sea-ice concentration anomalies either in winter （DJF） or in spring （MAM） are highlighted. Furthermore, new links between the Arctic sea ice and the extreme weather in India and Eurasia are proposed. The methodology developed in this study can be further applied to identify other remote impacts of the Arctic sea ice variability.
文摘The influence of solid solution treatments on the dissolution of carbides precipitates,the grain size,and the hardness of high strength low expansion alloy were investigated through XRD analysis,microstructure observations,and theoretical computation.It was seen that most primary Mo2C type carbide band dissolved in a temperature range of 1 100-1 150 ℃.When the temperature was over 1 200 ℃,the grain size increased remarkably,which led to the reduction of hardness.
