Insight into the Influence of Punch Velocity and Thickness on Forming Limit Diagrams of AA 6061 Sheets—Numerical and Experimental Analyses

Sasan Sattarpanah Karganroudi,Ahmad Aminzadeh,Ramin Hashemi,Davood Rahmatabadi,Hussein Ibrahim,Sahar Jamalian,Shahab Shojaei

doi:10.3390/met11122010

Sasan Sattarpanah Karganroudi, Ahmad Aminzadeh + Show 5 more

Open Access

https://doi.org/10.3390/met11122010

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Abstract

In this article, the forming limit diagram (FLD) for aluminum 6061 sheets of thicknesses of 1 mm and 3 mm was determined numerically and experimentally, considering different punch velocities. The punch velocity was adjusted in the range of 20 mm/min to 200 mm/min during the Nakazima test. A finite element (FE) simulation was carried out by applying the Johnson–Cook material model into the ABAQUSTM FE software. In addition, a comparison between the simulation and the experimental results was made. It was observed that by increasing the punch velocity, the FLD also increased for both thicknesses, but the degree of the improvement was different. Based on these results, we found a good agreement between numerical and experimental analyses (about 10% error). Moreover, by increasing the punch velocity from 20 mm/min to 100 mm/min in 1 mm-thick specimens, the corresponding FLD increased by 3.8%, while for 3 mm-thick specimens, this increase was 5.2%; by increasing the punch velocity from 20 mm/min to 200 mm/min in the 3 mm-thick sheets, the corresponding FLD increased by 9.3%.

Highlights

Today, the manufacturing of many industrial products has become relevant to sheet metal forming processes
Their research showed that both strain rate and temperature negatively and positively affect the forming limit diagram (FLD) of AA5086, respectively
The research of Wang et al [15] indicated that punch velocity and temperature had a substantial effect on the forming limits of AA2024 according to the tensile test and the cup punch test

Summary

Introduction

The manufacturing of many industrial products has become relevant to sheet metal forming processes. Studying the effects of new sheet metal forming methods such as high-rate processes on forming limit diagrams (FLDs) is necessary. Chu et al determined the forming limit diagrams of AA5086 under various strain rates (0.02, 0.2, and 2 s−1) and temperatures (20, 150, and 200 ◦C) using the Marciniak test [13].

Results

Conclusion