【摘 要】
：
Currently the Aluminum Alloy Resistance Spot Welding (AA-RSW) has been extensively used for light weight automotive body-in-white manufacturing.However the aluminum alloys such as AA5182 have inferior
【出 处】
：
2012 Postdoctoral Symposium of China on Materials Science &
论文部分内容阅读
Currently the Aluminum Alloy Resistance Spot Welding (AA-RSW) has been extensively used for light weight automotive body-in-white manufacturing.However the aluminum alloys such as AA5182 have inferior weldability for forming the joint due to their high reflectiveness to heat and light, therefore it is necessary to further develop the high performance control strategy and the set-up of a new welding schedule.And the welding process identification is the essential issue where the difficulty arises from the fact that the AA-RSW is a nonlinear time-varying uncertain process which couples the thermal, electrical, mechanical and metallurgical dynamics.To understand this complicated physical phenomenon a novel dual-phase M-series pseudo-random electrical pattern is adopted to excite the AA-RSW electrical-thermal process and the thermal response is recorded according to the welding power outputs.Based on the experimental information the transfer function of an AA-RSW electrical-thermal mechanism is identified, and the optimum model order and parameters are determined.Subsequently a control-oriented D.C.AA-RSW model is established to explore the welding power control algorithm.The simulated results from the control model show their agreement with the experimental data, which validates its feasibility for corresponding welding control.
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