| In order to achieve electrical contact of connecter and wire, welding becomes themost popular connecting method in the modern industry. In the development ofelectronic equipment processing and assembly technology towards the miniaturization,miniaturization and environment friendly direction, the diameter of the coaxial pins isalso getting smaller. If the traditional welding methods, like the manual welding, hot airwelding and soldering iron (Hot-bar) welding, are taken the damage to lines isinevitable, and the short-circuiting between devices can be found easily. Additionally,the shield between the micro-coaxial cables is also difficult to traditional solderingtechnology.This thesis is based on a Micro-USB v2.0connector, and the laser solderingwelding technology is utilized to achieve the assembly of wire and electronic connectors.Laser welding technology is a more advanced welding technique, the characteristics oflaser heat source is local concentrated heating and fast cooling. Laser weldingtechniques can meet the requirements of the micro wire solder interconnect, thus toachieve solder microstructure refinement and improve the solder fatigue lifespan. Thisthesis has already solved a series of technical problems during the processing ofelectronic equipment in stripping, chucking, the parameters connected with the weldingtest are determined and effects of the parameters are also studied to complete the test ofthe electronic connector of laser soldering. The finite element software ANSYS isutilized for the laser soldering process of electronic connectors, to draw the temperaturefield and stress fields accordingly. In addition, the viscoplastic ANAND constitutiveequation is utilized for describing the mechanics response of the solder joints under theinfluence of thermal cycle load, the increment of strain energy density in each cycleabout the solder joint dangerous units is obtained by finite element method, andpredicting the thermal fatigue failure of solder joints based on the strain energy densityincrement Coffin-Manson correction equations.The results show that the numerical simulation results are consistent with theexperimental results to verify the laser soldering process parameters and make them meet the electronic connector welding process standards. Calculating the thermalfatigue of solder joints is4579times under the thermal cycle load, this result accordwith the quality standards of the Micro-USB connector, to further verify the lasersoldering process parameters and make them meet the electronic connector weldingprocess standards. |
