Investigation on the anisotropy behavior of copper strips processed by a combination of FSP and ECAP

Abstract

In this study, friction stir processed (FSP) pure copper sheet was equal channel angular pressed (ECAP). The purpose was to investigate the influence of ECAP on the microstructure and mechanical properties of the FSP-treated copper sheet. The dynamically recrystallized grained structure with the average grain size of ∼13 µm was found in the stir zone of the FSP. It was also revealed that FSP caused the enhancement of ultimate tensile strength compared to that of the base metal. Also, it was observed that ECAP led to further grain refinement and a tighter distribution of grains. A refined microstructure with an average grain size of ∼ 2 µm was achieved in copper sheets through FSP, followed by ECAP. The tensile strengths of the ECAP specimens were significantly increased to about 61 and 50% compared to the strengths of base metal and FSP, respectively. An overview of the results of this study showed that combined FSP/ECAP is an effective method for the mechanical improvement of the pure copper sheets.

The Cold Angular Rolling Process of Copper Sheets: Unraveling Plastic Deformation Behavior and Unveiling Microstructural Transformations

“…For comparison purposes, representative studies on Cu and its alloys processed by these SPD techniques are summarized and compared with the present work. Table 4 shows the summary of the continuous [ 10,54–56,99–111 ] and multiple‐step SPD techniques [ 11,53,57,67–69,71,73,112–124 ] on pure Cu and alloys with the processing condition, imposed strain, final grain size d, achieved hardness value, yield strength , ultimate tensile strength , elongation δ , tensile strain rates applied for acquiring the mechanical properties, and references.…”

“…For comparison purposes, representative studies on Cu and its alloys processed by these SPD techniques are summarized and compared with the present work. Table 4 shows the summary of the continuous [10,[54][55][56][99][100][101][102][103][104][105][106][107][108][109][110][111] and multiple-step SPD techniques [11,53,57,[67][68][69]71,73,[112][113][114][115][116][117][118][119][120][121][122][123][124] on pure Cu and alloys with the processing condition, imposed strain, final 2020) [54] Cu (99.99%) SRAR (%15 mm s À1 , route A, 6 passes) %0.6 per pass 5.2 100-120 343.7 388.5 13.9 1.0 Â 10 À3 Lee et al ( 2018), [105] (2019) [106] Cu (99.99%) SRAR (%15 mm s À1 , route C, 6 passes) 2020) [107] Cu-0.…”

“…A conventional plot of yield strength versus ductility illustrating the relationship between yield strength and ductility generated by adapting a previously published plot [16] for pure Cu and alloys after continuous [10,[54][55][56][99][100][101][102][103][104][105][106][107][108][109][110][111] and multiple-step SPD processes. [11,53,57,[67][68][69]71,73,[112][113][114][115][116][117][118][119][120][121][122][123][124] The white circles are a set of representative datum points for Cu after different cold rolling percentages, [16] Cu alloys from the database [127] are shown in gray, and a dotted curve shows a border for the classic strength and ductility limit for general Cu alloys.…”