The optimization of the loading path for T-shape tube hydroforming using adaptive radial basis function

The success of the T-shape tube hydroforming process requires a combination of internal pressure and axial and counter punch actions. The objective of this study is to introduce the adaptive radial basis function and demonstrate its accuracy and efficiency through a numerical example, to determine the optimal loading parameters in T-shape tube hydroforming process. The finite element model is developed with the explicit dynamic finite element code LS-DYNA and validated against the experimental work. The Taguchi method based on variance of analysis technique is used to screen the important loading parameters, which have a significant effect on the forming quality, such as the maximum thinning ratio, protrusion height and contact area, etc, from a number of potential loading parameters. The contact area is considered as the objective while the maximum thinning ratio and protrusion height are regarded as the constraints, and then the optimal loading parameters are obtained by adaptive radial basis function after several iterations. The results show that a significant improvement in the contact area is achieved while the results of the minimum thickness and protrusion height do not become worse.