In this study,adopting uniform design method established a mathematical model to prepare multi-element active flux. GH4169 superalloy plates were welded by the Nd: YAG laser equipment with the prepared active flux. Th...In this study,adopting uniform design method established a mathematical model to prepare multi-element active flux. GH4169 superalloy plates were welded by the Nd: YAG laser equipment with the prepared active flux. The results show all kinds of fluxes increase the depth to width ratio and the multi-component systems are more significant. The largest increment of the weld depth to width ratio is 159%,obtained by using of the F12 series flux. It is proved that by using of the active flux to increase the depth to width ratio of micro laser welding is feasible.展开更多
Multiwall carbon nanotubes(MWCNTs) reinforced magnesium matrix(MWCNTs/Mg) composites were successfully fabricated by friction stir processing(FSP). Microstructure and microwave-absorption properties of WCNTs/Mg compos...Multiwall carbon nanotubes(MWCNTs) reinforced magnesium matrix(MWCNTs/Mg) composites were successfully fabricated by friction stir processing(FSP). Microstructure and microwave-absorption properties of WCNTs/Mg composites are studied. The results show that with increasing the MWCNTs content to 7.1% in volume fraction,the agglomeration of MWCNTs is found in the WCNTs/Mg composites. The addition of MWCNTs has little effect on microwave-absorption properties. With increasing the frequency from 2 GHz to 18 GHz,the microwave absorption of the composites decreases. Compared with the absorption loss of the MWCNTs,the reflection loss of base material takes the most part of the loss of the microwave,and the increase of the reflection loss can promote electromagnetic shielding properties of the composites. Moreover,the electromagnetic shielding properties of the composites are less than-85 d B in the lower frequency range from 0.1 MHz to 3 GHz. With increasing the content of MWCNTs,the electrical conductivity of the composites is decreased,and the electromagnetic shielding properties is slightly enhanced.展开更多
基金supported by National Natural Science Foundation of China(No.51565040)Science and Technology Planning Project of Jiangxi Province(20151BBE50034,20133BBE50021)Aviation Science Funds of China(2014ZE56016)
文摘In this study,adopting uniform design method established a mathematical model to prepare multi-element active flux. GH4169 superalloy plates were welded by the Nd: YAG laser equipment with the prepared active flux. The results show all kinds of fluxes increase the depth to width ratio and the multi-component systems are more significant. The largest increment of the weld depth to width ratio is 159%,obtained by using of the F12 series flux. It is proved that by using of the active flux to increase the depth to width ratio of micro laser welding is feasible.
基金supported by the National Natural Science Foundation of China(No.51265042)
文摘Multiwall carbon nanotubes(MWCNTs) reinforced magnesium matrix(MWCNTs/Mg) composites were successfully fabricated by friction stir processing(FSP). Microstructure and microwave-absorption properties of WCNTs/Mg composites are studied. The results show that with increasing the MWCNTs content to 7.1% in volume fraction,the agglomeration of MWCNTs is found in the WCNTs/Mg composites. The addition of MWCNTs has little effect on microwave-absorption properties. With increasing the frequency from 2 GHz to 18 GHz,the microwave absorption of the composites decreases. Compared with the absorption loss of the MWCNTs,the reflection loss of base material takes the most part of the loss of the microwave,and the increase of the reflection loss can promote electromagnetic shielding properties of the composites. Moreover,the electromagnetic shielding properties of the composites are less than-85 d B in the lower frequency range from 0.1 MHz to 3 GHz. With increasing the content of MWCNTs,the electrical conductivity of the composites is decreased,and the electromagnetic shielding properties is slightly enhanced.