Creep deformation can be classified as homogeneous flow and inhomogeneous flow in bulk metallic glass(BMG).In order to understand the conversion conditions of the two types of creep deformation,the effect of loading r...Creep deformation can be classified as homogeneous flow and inhomogeneous flow in bulk metallic glass(BMG).In order to understand the conversion conditions of the two types of creep deformation,the effect of loading rate on the creep behavior of a Ti_(40)Zr_(10)Cu_(47)Sn_(3)(at.%)BMG at ambient temperature was investigated using nanoindentation and molecular dynamic simulation.Results indicate that at low loading rates,many serrations appear in loading stage,leading to inhomogeneous serrated flow in the creep stage.When the loading rate is high enough,the creep deformation tends to be homogeneous.The related mechanism responsible for the rate-dependent creep behavior is attributed to the number of pre-existing major shear bands which is influenced significantly by the loading rate.展开更多
In this study ETMA （Equilateral Triangular Microstrip Antennas） are designed to form dual frequency by inserting two shorting pins. Microstrip patch antennas＇ resonant frequencies with two shorting pins are represe...In this study ETMA （Equilateral Triangular Microstrip Antennas） are designed to form dual frequency by inserting two shorting pins. Microstrip patch antennas＇ resonant frequencies with two shorting pins are represented in this study by not only considering the theoretical results but also considering the both simulated and experimental results. For each geometry, positions of shorting pins are varied and effects of these variations are analyzed. The presented patch antennas in literature which have the same shape with shorting pin and without shorting pin are compared and results are presented. The methods in literature presented for estimating the resonant frequency depends on analytical methods which are originated from curve fitting. The results of this study will be the basement of the latter studies that predict the resonant frequencies of mentioned antennas before producing the antenna so that the engineers handle the problem by saving the time and estimating the frequency before production.展开更多
基金supported by the National Key Research and Development Program of China(No.2016YFB1100103)the National Natural Science Foundation of China(No.51771233)+2 种基金Key Research and Development Program of Hunan Province,China(No.2016JC2003)China Postdoctoral Science Foundation(No.2018M633164)Fundamental Research Funds for the Central Universities of Central South University,China(Nos.2018ZZTS127,CX20190190,2019ZZTS134)。
文摘Creep deformation can be classified as homogeneous flow and inhomogeneous flow in bulk metallic glass(BMG).In order to understand the conversion conditions of the two types of creep deformation,the effect of loading rate on the creep behavior of a Ti_(40)Zr_(10)Cu_(47)Sn_(3)(at.%)BMG at ambient temperature was investigated using nanoindentation and molecular dynamic simulation.Results indicate that at low loading rates,many serrations appear in loading stage,leading to inhomogeneous serrated flow in the creep stage.When the loading rate is high enough,the creep deformation tends to be homogeneous.The related mechanism responsible for the rate-dependent creep behavior is attributed to the number of pre-existing major shear bands which is influenced significantly by the loading rate.
文摘In this study ETMA （Equilateral Triangular Microstrip Antennas） are designed to form dual frequency by inserting two shorting pins. Microstrip patch antennas＇ resonant frequencies with two shorting pins are represented in this study by not only considering the theoretical results but also considering the both simulated and experimental results. For each geometry, positions of shorting pins are varied and effects of these variations are analyzed. The presented patch antennas in literature which have the same shape with shorting pin and without shorting pin are compared and results are presented. The methods in literature presented for estimating the resonant frequency depends on analytical methods which are originated from curve fitting. The results of this study will be the basement of the latter studies that predict the resonant frequencies of mentioned antennas before producing the antenna so that the engineers handle the problem by saving the time and estimating the frequency before production.
