To address the problems of large welding deformation and splashing in the resistance spot welding of the lubricating oil cooler plate,the laser spot welding was employed,instead of the resistance spot welding,and a no...To address the problems of large welding deformation and splashing in the resistance spot welding of the lubricating oil cooler plate,the laser spot welding was employed,instead of the resistance spot welding,and a novel laser spot welding was proposed,i.e.,laser multi-section welding.The major processes involved in this study referred to a finite element model of pulsed laser lap welding built by adopting SYSWELD simulation software,as well as the laser welding of various welding methods.The effect of different welding methods on the welding quality was studied,the parameters of the average power and the duty cycle were optimized in line with the comparative analysis of the experimentally achieved results and the numerical simulation.As indicated from the experimentally achieved results,when the new 6-sections welding method was adopted,the resulting welded joint achieved the most uniform heat input and the largest welding fusion area,and the tensile properties exhibited by the welded joints were significantly enhanced,whereas some pores remained.By altering the duty cycle,pores could be eliminated to further improve the quality of the joint.The mentioned process method could tackle down the problems facing conventional resistance spot welding.Furthermore,it was capable of improving the uneven heat input of the laser spot welding.展开更多
We propose an ultrabroad-band 1R regenerator utilizing a multi-section quantum-dot semiconductor optical amplifier. Due to the reduced electron states, quantum dot is beneficial in broadening the gain spectrum and low...We propose an ultrabroad-band 1R regenerator utilizing a multi-section quantum-dot semiconductor optical amplifier. Due to the reduced electron states, quantum dot is beneficial in broadening the gain spectrum and lowering the noise figure. Combining this with a multi-section structure drastically improves the gain equality among the different bound states, leading to an increase in the maximum output power and an improvement of the noise figure.展开更多
基金Department of Science and Technology of Jilin Province of China(Grant No.20180201063GX).
文摘To address the problems of large welding deformation and splashing in the resistance spot welding of the lubricating oil cooler plate,the laser spot welding was employed,instead of the resistance spot welding,and a novel laser spot welding was proposed,i.e.,laser multi-section welding.The major processes involved in this study referred to a finite element model of pulsed laser lap welding built by adopting SYSWELD simulation software,as well as the laser welding of various welding methods.The effect of different welding methods on the welding quality was studied,the parameters of the average power and the duty cycle were optimized in line with the comparative analysis of the experimentally achieved results and the numerical simulation.As indicated from the experimentally achieved results,when the new 6-sections welding method was adopted,the resulting welded joint achieved the most uniform heat input and the largest welding fusion area,and the tensile properties exhibited by the welded joints were significantly enhanced,whereas some pores remained.By altering the duty cycle,pores could be eliminated to further improve the quality of the joint.The mentioned process method could tackle down the problems facing conventional resistance spot welding.Furthermore,it was capable of improving the uneven heat input of the laser spot welding.
文摘We propose an ultrabroad-band 1R regenerator utilizing a multi-section quantum-dot semiconductor optical amplifier. Due to the reduced electron states, quantum dot is beneficial in broadening the gain spectrum and lowering the noise figure. Combining this with a multi-section structure drastically improves the gain equality among the different bound states, leading to an increase in the maximum output power and an improvement of the noise figure.
