Numerical Study on the Plastic Forming of Doubly Curved Surfaces of Aluminum Foam Sandwich Panel Using 3D Voronoi Model

Jiaxin Gao,Zhongyi Cai,Xi Zhang,Mingwei Wang,Qingmin Chen,Ya Zhang

doi:10.3390/met11050675

Abstract

This paper presents a numerical investigation on the plastic forming of doubly curved surfaces of aluminum foam sandwich panel (AFSP). A mesoscopic 3D Voronoi model that can describe the structure of closed-cell aluminum foam relatively realistically was established, and a series of numerical simulations using the model of the sandwich panel with a Voronoi foam core were conducted on the plastic forming of two typical doubly curved surfaces including spherical and saddle-shaped surfaces of AFSPs to analyze the deformation behaviors and the forming defects in detail. Multi-point forming experiments of spherical and saddle-shaped AFSPs with different target radii were implemented and the doubly curved panels with good forming quality were obtained. The simulated results of the surface illumination maps, the face sheet profiles, and the maximum strain differences in selected areas of the face sheet and the experimental results indicated that the Voronoi AFSP model can reflect the actual defects occurred in the plastic forming of doubly curved sandwich panels, and the high forming accuracy of the sandwich panel model was also demonstrated in terms of the shape error and the thickness variation.

Highlights

Owing to its face sheet-core-face sheet sandwich structure and ultra-light closed-cell porous foam core, aluminum foam sandwich panel (AFSP) is characterized by its high specific strength and stiffness, and outstanding thermal insulation, energy absorption, and vibration damping, which has been widely used in various engineering domains [1,2]
Equivalent strains distributed on the inner foam cores of the spherical and saddle-shaped AFSPs are displayed in Figure 8a and b respectively
No de-bonding defect was found in the practical products, and it is proved that the sandwich panel model without considering the adhesive layer is acceptable

Summary

Introduction

Owing to its face sheet-core-face sheet sandwich structure and ultra-light closed-cell porous foam core, aluminum foam sandwich panel (AFSP) is characterized by its high specific strength and stiffness, and outstanding thermal insulation, energy absorption, and vibration damping, which has been widely used in various engineering domains [1,2]. Closed-cell aluminum foams can be well represented by a 3D Voronoi model since the generation process of the model is similar to the actual foaming process. FE model for the numerical simulation on the MPF of saddle-shaped AFSP

Numerical Results Analysis

Multi-Point Forming Experiment

Experimental Results and Analyses

Conclusions