Formability of the 5754-Aluminum Alloy Deformed by a Modified Repetitive Corrugation and Straightening Process

Abstract

Sheets of 5754-aluminum alloy processed by a modified repetitive corrugation and straightening (RCS) process were tested in order to measure their formability. For this purpose, forming limit curves were derived. They showed that the material forming capacity decreased after being processed by RCS. However, they kept good formability in the initial stages of the RCS process. The formability study was complemented with microstructural analysis (derivation of texture) and mechanical tests to obtain the strain-rate sensitivity. The texture analysis was done by employing X-ray diffraction, obtaining pole figures, and the orientation distribution function. It was noticed that the initial texture was conserved after successive RCS passes, but the intensity dropped. RCS process did not induce β-fiber, contrary to common deformation process. The strain-rate sensitivity coefficient was measured through tensile tests at different temperatures and strain rates; the coefficient of the samples processed after one and two passes were still relatively high, indicating the capacity to delay necking, in agreement with the good formability observed in the initial passes of the RCS process.

Study on the Formability and Texture evolution of AA6061 Alloy Processed by Repetitive Corrugation and Straightening.

“…Their results showed that the FLD 0 still decreased for the higher processed sample temperatures. Similarly, Ezequiel et al (2020) showed that the FLD 0 and biaxial ductility of Al 5754 aluminum alloy processed by RCS decreased after one pass, while a significant loss of the forming capacity was observed after two RCS passes. Lapovok et al (2008) studied the formability of the Al-6111 alloy processed at room temperature by ECAP up to 2 passes.…”

“…Under these conditions, the strain rate sensitivity parameter at each temperature becomes a key indicator of the forming capacity. This parameter can be interpreted as the ability of the material to keep the homogeneous deformation and delay fracture as a function of the strain rate applied (Chen et al, 2017;Ezequiel et al, 2020). Moreover, the grain size also has a considerable effect during the hot forming processes, especially when the grain size is fine enough (usually below 10 μm) to promote superplastic behavior, which in turn allows extraordinarily large homogeneous elongations (Khamei & Dehghani, 2015).…”

Heterostructured Materials by Severe Plastic Deformation: Overview and Perspectives

“…120) Examples of multimodal structures have been widely reported in the literature. 119,[121][122][123][124][125][126] The synergistic performance of nanometric, UFG, and micrometric grains which coexist in the same structure, has been shown to increase the bulk yield strength. 121) A synergistic performance to improve electrochemical corrosion resistance and stress corrosion cracking has also been reported in wide-grain size distribution Al-7075 alloy processed by RCS.…”