Optimization of Clinching Tools by Integrated Finite Element Model and Genetic Algorithm Approach

doi:10.1007/s12204-018-1995-9

Abstract

Abstract: Clinching is a convenient and efficient cold forming process that can join two sheets without any additional part. This study establishes an intelligent system for optimizing the clinched joint. Firstly, a mathematical model which introduces the ductile damage constraint to prevent cracking during clinching process is proposed. Meanwhile, an optimization methodology and its corresponding computer program are developed by integrated finite element model (FEM) and genetic algorithm (GA) approach. Secondly, Al6061-T4 alloy sheets with a thickness of 1.4mm are used to verify this optimization system. The optimization program automatically acquires the largest axial strength which is approximately equal to 872N. Finally, sensitivity analysis is implemented, in which the influence of geometrical parameters of clinching tools on final joint strength is analyzed. The sensitivity analysis indicates the main parameters to influence joint strength, which is essential from an industrial point of view.

Key words: mechanical clinching| optimization design| genetic algorithm (GA)| ductile damage

摘要： Clinching is a convenient and efficient cold forming process that can join two sheets without any additional part. This study establishes an intelligent system for optimizing the clinched joint. Firstly, a mathematical model which introduces the ductile damage constraint to prevent cracking during clinching process is proposed. Meanwhile, an optimization methodology and its corresponding computer program are developed by integrated finite element model (FEM) and genetic algorithm (GA) approach. Secondly, Al6061-T4 alloy sheets with a thickness of 1.4mm are used to verify this optimization system. The optimization program automatically acquires the largest axial strength which is approximately equal to 872N. Finally, sensitivity analysis is implemented, in which the influence of geometrical parameters of clinching tools on final joint strength is analyzed. The sensitivity analysis indicates the main parameters to influence joint strength, which is essential from an industrial point of view.

关键词: mechanical clinching| optimization design| genetic algorithm (GA)| ductile damage

CLC Number:

TG 938

WANG Menghan* (王梦寒), XIAO Guiqian (肖贵乾), WANG Jinqiang (王晋强), LI Zhi (李志). Optimization of Clinching Tools by Integrated Finite Element Model and Genetic Algorithm Approach[J]. Journal of Shanghai Jiao Tong University (Science), 2019, 24(2): 262-272.

References 18

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