The present paper investigates the welding forming,microstructure and shear tensile test of lap joints with large thickness ratio which were fabricated by laser screw welding(LSW)and resistant spot welding(RSW).The co...The present paper investigates the welding forming,microstructure and shear tensile test of lap joints with large thickness ratio which were fabricated by laser screw welding(LSW)and resistant spot welding(RSW).The comparison was conducted on two kinds of lap joints,galvanized sheet and hot pressed steel(GS-HPS),galvanized sheet and high strength steel(GS-HS).The microstructure and fracture morphology were analyzed by optical microscope.It was demonstrated that with large thickness ratio the sound lap joint of GS-HS could be obtained by LSW regardless of the irradiation of laser beam from thick metal to sheet or otherwise,and the morphology shows it is better when the laser is irradiated on the thick metal.Nevertheless,when the laser beam was applied on thick metal of HPS,blind hole or blowhole was formed in the center of joint,which is attributed to the shrinkage during solidification of the molten pool.Small pores or dispersed porosity appeared on the faying face of the joint without predetermined gap which provides the degassing.However,the increase of predetermined gap could reduce the shear strength and nugget size.Two kinds of joints made by LSW have superior shear strength than those made by RSW when the laser were applied on galvanized sheet.展开更多
Friction element welding technology is rich of flow drill screws combined with friction welding technology and is developed for the hot-forming steel plate and aluminum alloy welding of car body-in-white.In this paper...Friction element welding technology is rich of flow drill screws combined with friction welding technology and is developed for the hot-forming steel plate and aluminum alloy welding of car body-in-white.In this paper,the principle of RES welding technology,equipment,technical characteristics,application condition and welding parameters are analyzed systematically.Moreover,the changing laws of welding parameters and welded joint quality control standards are described,which provides the necessary technical support for safety and light-weight car body design requirements.This study has high practical application value,and enriches the automobile body joining technology.展开更多
为配合车身轻量化生产中焊接机器人选型,文章以热熔自攻丝工艺中孔成形阶段铆枪最大下压力为参考标准,对其工艺影响因素进行研究。以1.2 mm RC5754+3.5 mm 6082-T6铝合金板件为研究对象,基于正交试验研究螺钉转速、进给速度以及监测设定...为配合车身轻量化生产中焊接机器人选型,文章以热熔自攻丝工艺中孔成形阶段铆枪最大下压力为参考标准,对其工艺影响因素进行研究。以1.2 mm RC5754+3.5 mm 6082-T6铝合金板件为研究对象,基于正交试验研究螺钉转速、进给速度以及监测设定值3个参数对该工艺中最大下压力的影响规律,运用极差分析法分析得到孔成形阶段最优工艺参数组合以及对应的铆枪最大下压力。试验结果表明,分析得到的优化参数组合可以提高铆接质量,同时优化后的铆枪最大下压力可以为实际生产中铆接机器人的型号选择提供参考,节约成本。展开更多
文摘The present paper investigates the welding forming,microstructure and shear tensile test of lap joints with large thickness ratio which were fabricated by laser screw welding(LSW)and resistant spot welding(RSW).The comparison was conducted on two kinds of lap joints,galvanized sheet and hot pressed steel(GS-HPS),galvanized sheet and high strength steel(GS-HS).The microstructure and fracture morphology were analyzed by optical microscope.It was demonstrated that with large thickness ratio the sound lap joint of GS-HS could be obtained by LSW regardless of the irradiation of laser beam from thick metal to sheet or otherwise,and the morphology shows it is better when the laser is irradiated on the thick metal.Nevertheless,when the laser beam was applied on thick metal of HPS,blind hole or blowhole was formed in the center of joint,which is attributed to the shrinkage during solidification of the molten pool.Small pores or dispersed porosity appeared on the faying face of the joint without predetermined gap which provides the degassing.However,the increase of predetermined gap could reduce the shear strength and nugget size.Two kinds of joints made by LSW have superior shear strength than those made by RSW when the laser were applied on galvanized sheet.
文摘Friction element welding technology is rich of flow drill screws combined with friction welding technology and is developed for the hot-forming steel plate and aluminum alloy welding of car body-in-white.In this paper,the principle of RES welding technology,equipment,technical characteristics,application condition and welding parameters are analyzed systematically.Moreover,the changing laws of welding parameters and welded joint quality control standards are described,which provides the necessary technical support for safety and light-weight car body design requirements.This study has high practical application value,and enriches the automobile body joining technology.
文摘为配合车身轻量化生产中焊接机器人选型,文章以热熔自攻丝工艺中孔成形阶段铆枪最大下压力为参考标准,对其工艺影响因素进行研究。以1.2 mm RC5754+3.5 mm 6082-T6铝合金板件为研究对象,基于正交试验研究螺钉转速、进给速度以及监测设定值3个参数对该工艺中最大下压力的影响规律,运用极差分析法分析得到孔成形阶段最优工艺参数组合以及对应的铆枪最大下压力。试验结果表明,分析得到的优化参数组合可以提高铆接质量,同时优化后的铆枪最大下压力可以为实际生产中铆接机器人的型号选择提供参考,节约成本。
