Algorithm-based design of mechanical joining processes

Mathias Jäckel,Welf-Guntram Drossel,Tobias Falk

doi:10.1007/s11740-022-01121-2

Abstract

In this paper, the development of algorithm-based process models for the mechanical joining process self-pierce riveting with semi-tubular rivet (SPR-ST) is described. Therefore, an extensive experimental and numerical database regarding the SPR-ST process and strength of steel and aluminum joints with tensile strengths of the sheets between 200 and 1000 MPa was generated for the building of the models. This process data could then be used for the training and evaluation of different prediction algorithms. Furthermore, the simulation data is applied to predict the entire contour (mesh) of non-simulated joints. This includes the visualization of output values such as strains, stresses and damage for each element and node of the mesh. That approach enables to obtain more information about the joint than just discrete values such as interlock or strength.

Highlights

The design of mechanical joining processes like self-pierce riveting with semi-tubular rivet (SPR-ST) for production involves time-consuming, experimental test series in which process parameters such as the rivet or die geometry are varied iteratively and based on experience until a suitable joint contour and strength is achieved
The progress due to the mentioned and other research work, the further development of simulation software systems and the constant advances in computer technology have contributed to the fact that the finite element method (FEM) simulation of SPR-ST of classical multi material joints made of sheet metal materials can be automated and carried out with high accuracy and with computing times of significantly less than one hour [6]
0.75 models such as Gradient Boosted Decision Tree (GBDT) and Multilayer perceptron—artificial neural network (MLP) show a significant increase in prediction accuracy

Summary

Introduction

The design of mechanical joining processes like self-pierce riveting with semi-tubular rivet (SPR-ST) for production involves time-consuming, experimental test series in which process parameters such as the rivet or die geometry are varied iteratively and based on experience until a suitable joint contour and strength is achieved. The progress due to the mentioned and other research work, the further development of simulation software systems and the constant advances in computer technology have contributed to the fact that the FEM simulation of SPR-ST of classical multi material joints made of sheet metal materials can be automated and carried out with high accuracy and with computing times of significantly less than one hour [6] This opens up the possibility to perform a larger number of FEM calculations based on statistical design of experiments to be used as data to build regression models and analyze the SPR-ST process from a mathematical point of view [7], to use. Rm/Rp0,2 in MPa Thickness in mm EN AW-6016 T4 EN AW-5182 CR210IF DX53D HCT600XD HCT780XD HCT980XG

Experimental and numerical process data mining

Joint characteristics and strength prediction

Prediction and visualization of entire joint contours and output parameters

Design

Findings

Summary and outlook