Experimental and Numerical Studies of Sheet Metal Forming with Damage Using Gas Detonation Process

Abstract

Abstract:Gas detonation forming is a high-speed forming method, which has the potential to form complex geometries, including sharp angles and undercuts, in a very short process time. Despite many efforts being made to develop detonation forming, many important aspects remain unclear and have not been studied experimentally, nor numerically in detail, e.g., the ability to produce sharp corners, the effect of peak load on deformation and damage location and its propagation in the workpiece. In the present work, DC04 steel cups were formed using gas detonation forming, and finite element method (FEM) simulations of the cup forming process were performed. The simulations on 3D computational models were carried out with explicit dynamic analysis using the Johnson-Cook material model. The results obtained in the simulations were in good agreement with the experimental observations, e.g., deformed shape and thickness distribution. Moreover, the proposed computational model was capable of predicting the damage initiation and evolution correctly, which was mainly due to the high-pressure magnitude or an initial offset of the workpiece in the experiments.

Deformation of Stacked Metallic Sheets by Shock Wave Loading

“…Moreover, the loading rate in the numerical model is very sensitive, even a little change in a load can affect the extreme change in model results. Therefore, we used the precisely same experimental loading curve in numerical simulations using well calibrated measuring devices [21][22][23].…”

“…In our previous work, we have studied DC04 metal forming using gas detonation forming process experimentally and numerically. Wherein, investigation of detonation pressure, deformed cup, thickness distribution, radial strain and damage in a cup were studied [21][22][23].…”

The Formation and Evolution of Shear Bands in Plane Strain Compressed Nickel-Base Superalloy

“…The effect of processing parameters on shear band propagation and unstable plastic was studied by analyzing the flow curves and microstructures. Furthermore, the finite element method (FEM) [14,15] was employed to interpret the occurrence and evolution of shear bands during the compression process. The present work for Inconel 718 superalloy yields important information for the optimizing of processing parameters and failure prediction under plane strain conditions.…”

Modelling and Simulation of Sheet Metal Forming Processes

“…Researchers were invited to submit innovative research papers on modelling and numerical simulation of sheet metal forming processes. Thirteen research papers were published in this Special Issue of Metals, entitled "Modelling and Simulation of Sheet Metal Forming Processes", which highlight some of the research trends in the field [2][3][4][5][6][7][8][9][10][11][12][13][14].…”

“…Forming processes involving non-isothermal temperature conditions and/or high strain rates require constitutive models with more parameters. In this context, the Johnson-Cook hardening law was used to study the gas detonation forming [2], which is a high-speed forming process, with the potential to form complex geometries, including sharp angles and undercuts. The authors neglected the thermal softening, but included damage evolution [2].…”