In the field of geology,it is necessary to get the information about the rock geological time,which includes absolute geologic age and relative geologic age .Tracing the evolutionary history of the earth is one of the...In the field of geology,it is necessary to get the information about the rock geological time,which includes absolute geologic age and relative geologic age .Tracing the evolutionary history of the earth is one of the research tasks of earth science.Time,space,material and motivation are the basic elements for studying geological processes and enviromnental evolution,and time is the basis for studying geological problems.A clear understanding of the interaction between the above elements will be able to clearly make sure the evolution of the earth and the conditions of rock formation.Nowadays,it is urgent to get the geochronological data of rocks for wide range comparison,so as to study the evolution trend and development rule of the earth's crust .展开更多
To give a further research on strengthening mechanism of binary Fe-Cu alloys dur- ing the aging process, the compositions, size distributions and volume fractions of precipitates were investigated by carbon extraction...To give a further research on strengthening mechanism of binary Fe-Cu alloys dur- ing the aging process, the compositions, size distributions and volume fractions of precipitates were investigated by carbon extraction replicas. Both the size and the volume fraction of precipitates increase with the aging time prolonged. The precip- itate sizes are corresponding with Weibull distribution. The stability of the sample aged for 35 rain is worse than that aged for 1800 min and 18000 min. The precipi- tate is Cu-rich phase in the early aging process, and Cu content increases with the prolonging aging time. Before aging peak, the precipitation of Cu-rich phase plays a dominant role in strengthening. The growth and the change in crystal structure of the precipitate particles are the main factors leading to the decrease in strengthening after the aging peak.展开更多
基金supported by the National Nature Science Foundation of China(Grant No.61405259)
文摘In the field of geology,it is necessary to get the information about the rock geological time,which includes absolute geologic age and relative geologic age .Tracing the evolutionary history of the earth is one of the research tasks of earth science.Time,space,material and motivation are the basic elements for studying geological processes and enviromnental evolution,and time is the basis for studying geological problems.A clear understanding of the interaction between the above elements will be able to clearly make sure the evolution of the earth and the conditions of rock formation.Nowadays,it is urgent to get the geochronological data of rocks for wide range comparison,so as to study the evolution trend and development rule of the earth's crust .
基金supported by the National Natural Science Foundation of China(No. 50671012)
文摘To give a further research on strengthening mechanism of binary Fe-Cu alloys dur- ing the aging process, the compositions, size distributions and volume fractions of precipitates were investigated by carbon extraction replicas. Both the size and the volume fraction of precipitates increase with the aging time prolonged. The precip- itate sizes are corresponding with Weibull distribution. The stability of the sample aged for 35 rain is worse than that aged for 1800 min and 18000 min. The precipi- tate is Cu-rich phase in the early aging process, and Cu content increases with the prolonging aging time. Before aging peak, the precipitation of Cu-rich phase plays a dominant role in strengthening. The growth and the change in crystal structure of the precipitate particles are the main factors leading to the decrease in strengthening after the aging peak.