Simulation And Experimental Researches On The Cu-Al Dissimilar Metals Laser Micro Welding For Miniature DC Motor Terminal

In order to solve the problem of loose between the brush and terminal component, to reduce the cost and to meet the requirement of automation manufacture, the aluminum alloy A1100 is used as the substitution of C2680( Brass with Ni plated), and the mechanical assembly is instead with the laser micro welding to realize the connect of A1100 and C5210. The feasibility and the reliability of the presented technology are also verified.Based on ANSYS Workbench and Bilinear model, the numerical simulation is finished by programming the Gaussian heat source, and thus the effect of laser parameters on the temperature field and the residual stress field. The simulation results show that the peak temperature can reach 2146 ℃with the peak power of 3 KW, which assures the sound connection without the defect of welding penetration. As the temperature decreases, the weld pool decreases from the "cup" to the "bowl". The residual stress will cause a brush needle angle deformation.Referring to the numerical simulation results, the laser micro welding of C5210 and A1100 is performed with single laser pulse of 6 ms and the peak power of 3.0 KW and 3.8 KW, respectively. Through the analyses of welding joint crack, blowhole and the measurements of the hardness and the tensile strength, the conclusion.can be drawn that the peak power of 3.0 KW is better.The laser welded C5210 brush needle- A1100 terminal is used to produce the micro motor. The feasibility and the reliability of the presented technology are verified with the comparison of waveform, current, rotate speed, torque and the life to those of the original products.