Aiming at machining deeply small holes in TC4 alloy,a series of experiments were carried out on a self-developed multi-axis micro electrical discharge machining(micro-EDM)machine tool.To improve machining efficiency a...Aiming at machining deeply small holes in TC4 alloy,a series of experiments were carried out on a self-developed multi-axis micro electrical discharge machining(micro-EDM)machine tool.To improve machining efficiency and decrease relative wear of electrode in machining deeply small hole in TC4 alloy,many factors in micro-EDM,such as polarity,electrical parameters and supplying ways of working fluid were studied.Experimental results show that positive polarity machining is far superior to negative polarity machining;it is more optimal when open-circuit voltage,pulse width and pulse interval are 130 V,5μs and 15μs respectively on the self developed multi-axis micro-EDM machine tool;when flushing method is applied in micro-EDM,the machining efficiency is higher and relative wear of electrode is smaller.展开更多
The isotope shifts and hyperfine structures of seven optical transitions for all seven stable isotopes of Nd II were measured by using collinear fast-ion-beam laser spectroscopy.The nuclear parameterλwas obtained fro...The isotope shifts and hyperfine structures of seven optical transitions for all seven stable isotopes of Nd II were measured by using collinear fast-ion-beam laser spectroscopy.The nuclear parameterλwas obtained from the measured optical isotope shifts for all seven stable isotopes with improved accuracy.Theλvalues were analysed by using the Fermi distribution for the nuclear charge density.The values of δ<r^(2)>,δ<r^(4)>and δ<r^(6)>were determined.展开更多
基金Project(2006AA04Z323)supported by High-tech Research and Development Program of China。
文摘Aiming at machining deeply small holes in TC4 alloy,a series of experiments were carried out on a self-developed multi-axis micro electrical discharge machining(micro-EDM)machine tool.To improve machining efficiency and decrease relative wear of electrode in machining deeply small hole in TC4 alloy,many factors in micro-EDM,such as polarity,electrical parameters and supplying ways of working fluid were studied.Experimental results show that positive polarity machining is far superior to negative polarity machining;it is more optimal when open-circuit voltage,pulse width and pulse interval are 130 V,5μs and 15μs respectively on the self developed multi-axis micro-EDM machine tool;when flushing method is applied in micro-EDM,the machining efficiency is higher and relative wear of electrode is smaller.
基金Supported by the National Natural Science Foundation of China under Grant No.19984015.
文摘The isotope shifts and hyperfine structures of seven optical transitions for all seven stable isotopes of Nd II were measured by using collinear fast-ion-beam laser spectroscopy.The nuclear parameterλwas obtained from the measured optical isotope shifts for all seven stable isotopes with improved accuracy.Theλvalues were analysed by using the Fermi distribution for the nuclear charge density.The values of δ<r^(2)>,δ<r^(4)>and δ<r^(6)>were determined.
