Failure prediction of axi-symmetric cup in deep drawing and expansion processes

Abstract

Presented work deals with the prediction of the forming limit of food can obtained with deep drawing, reverse drawing and expansion operations. Two commonly used materials of TH330 steel and AA5352 aluminium alloy for packaging can production were studied. Finite element simulation (FEM) is an essential tool in the packaging industry to prevent different sheet metal forming difficulties such as failure under complex nonlinear strain paths and plastic anisotropic earing. In order to characterise the material plastic properties and to specify failure criteria, the uniaxial tensile, hydraulic bulge test, as well as the routines for obtaining forming limit curves were carried out. The input material data required for various material models are also described. Utilisation of advanced material models in numerical simulation require a large number of input data. Prediction of failure location in drawing and expansion of axi-symmetric cups were estimated for each material. The FEM results were verified by real experiments.

Material characterization and damage assessment of an AA5352 aluminium alloy using digital image correlation

“…Besides, Table 5 presents the mean value of calculated outcome compared with the ones reported by the literature. 4,35 In consequence, the amounts of n and r 90 acquired from DIC analysis agreed well with the literature. Small deviations verified the results and therefore they could be considered as a robust experimental data adopted for the future analyses of the AA5352 alloys.…”

“…In the case of the segment presented in Figure 4(d), medium grid, there is a different grid of lines, so it is feasible to acquire an evolution of n taking into account distinct pairs of lines, for example, considering the lines ab (from points 11 to 1) and id (from points 6 to 8), or the lines uv (from points 15 to 5) and ns (from points 8 to 10). Using equation (4) and these lines, it is conceivable to calculate n from strain data at these points. In the end, the segment shown in Figure 4(e) is known as fine grid, applicable for further analyses.…”

“…Regarding point D, it remains as the offset yield point (proof stress) used for yield stress calculation, Sy . Besides, point E is considered to calculate the material’s ultimate tensile strength, UTS and at the end, the material ruptured at point F. Therefore, material properties including E , Sy and UTS were characterized for AA5352 in accordance with true stress/strain diagram and compared with the values reported in the literature 4,35 (Table 5).…”

“…Besides, Table 5 presents the mean value of calculated outcome compared with the ones reported by the literature. 4,35…”

“…To characterize material properties in plastic and to regulate the failure criteria, uniaxial tensile tests were carried out to acquire forming limit diagrams. 4 Peixoto et al 5 determined the elasticity modulus of an aluminium alloy using different approaches such as frequency response, bending and tensile tests. Bruni et al 6 investigated double aluminium alloy specimens made of aluminium alloys AA6026 and AA6012 after pressing.…”