Mechanical Properties Enhancement of Dissimilar AA6061-T6 and AA7075-T651 Friction Stir Welds Coupled with Deep Rolling Process
The main purpose of this research was to enhance the mechanical properties of friction stir welds (FSW) in the dissimilar aluminum alloys 6061-T6 and 7075-T651. The welded workpiece has tensile residual stress due to the influence of the thermal conductivity of dissimilar materials, resulting in cra...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-09-01
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| Series: | Materials |
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| Online Access: | https://www.mdpi.com/1996-1944/15/18/6275 |
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| author | Pisit Kaewkham Wasawat Nakkiew Adirek Baisukhan |
| author_facet | Pisit Kaewkham Wasawat Nakkiew Adirek Baisukhan |
| author_sort | Pisit Kaewkham |
| collection | DOAJ |
| description | The main purpose of this research was to enhance the mechanical properties of friction stir welds (FSW) in the dissimilar aluminum alloys 6061-T6 and 7075-T651. The welded workpiece has tensile residual stress due to the influence of the thermal conductivity of dissimilar materials, resulting in crack initiation and less fatigue strength. The experiment started from the FSW process using the 2<sup>k</sup> full factorial with the response surface methodology (RSM) and central composite design (CCD) to investigate three factors. The experiment found that the optimal rotation speed and feed rate values were 979 and 65 mm/min, respectively. Then, the post-weld heat treatment process (PWHT) was applied. Following this, the 2<sup>k</sup> full factorial was used to investigate four factors involved in the deep rolling process (DR). The experiment found that the optimal deep rolling pressure and deep rolling offset values were 300 bar and 0.2 mm, respectively. Moreover, mechanical property testing was performed with a sequence of four design types of workpieces: FSW, FSW-PWHT, FSW-DR, and FSW-PWHT-DR. It was found that the FSW-PWHT-DR workpiece had an increase in tensile strength of up to 26.29% and increase in fatigue life of up to 129.47% when compared with the FSW workpieces, as well as a maximum compressive residual stress of −414 MPa. |
| first_indexed | 2024-03-09T23:18:19Z |
| format | Article |
| id | doaj.art-2f669c8a6a9d49ee88d226282f9dd0f9 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-09T23:18:19Z |
| publishDate | 2022-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-2f669c8a6a9d49ee88d226282f9dd0f92023-11-23T17:30:52ZengMDPI AGMaterials1996-19442022-09-011518627510.3390/ma15186275Mechanical Properties Enhancement of Dissimilar AA6061-T6 and AA7075-T651 Friction Stir Welds Coupled with Deep Rolling ProcessPisit Kaewkham0Wasawat Nakkiew1Adirek Baisukhan2Graduate Program in Industrial Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai 50200, ThailandDepartment of Industrial Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai 50200, ThailandDepartment of Industrial Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai 50200, ThailandThe main purpose of this research was to enhance the mechanical properties of friction stir welds (FSW) in the dissimilar aluminum alloys 6061-T6 and 7075-T651. The welded workpiece has tensile residual stress due to the influence of the thermal conductivity of dissimilar materials, resulting in crack initiation and less fatigue strength. The experiment started from the FSW process using the 2<sup>k</sup> full factorial with the response surface methodology (RSM) and central composite design (CCD) to investigate three factors. The experiment found that the optimal rotation speed and feed rate values were 979 and 65 mm/min, respectively. Then, the post-weld heat treatment process (PWHT) was applied. Following this, the 2<sup>k</sup> full factorial was used to investigate four factors involved in the deep rolling process (DR). The experiment found that the optimal deep rolling pressure and deep rolling offset values were 300 bar and 0.2 mm, respectively. Moreover, mechanical property testing was performed with a sequence of four design types of workpieces: FSW, FSW-PWHT, FSW-DR, and FSW-PWHT-DR. It was found that the FSW-PWHT-DR workpiece had an increase in tensile strength of up to 26.29% and increase in fatigue life of up to 129.47% when compared with the FSW workpieces, as well as a maximum compressive residual stress of −414 MPa.https://www.mdpi.com/1996-1944/15/18/6275friction stir weldingdeep rollingtensile strengthresidual stressfatigue life |
| spellingShingle | Pisit Kaewkham Wasawat Nakkiew Adirek Baisukhan Mechanical Properties Enhancement of Dissimilar AA6061-T6 and AA7075-T651 Friction Stir Welds Coupled with Deep Rolling Process Materials friction stir welding deep rolling tensile strength residual stress fatigue life |
| title | Mechanical Properties Enhancement of Dissimilar AA6061-T6 and AA7075-T651 Friction Stir Welds Coupled with Deep Rolling Process |
| title_full | Mechanical Properties Enhancement of Dissimilar AA6061-T6 and AA7075-T651 Friction Stir Welds Coupled with Deep Rolling Process |
| title_fullStr | Mechanical Properties Enhancement of Dissimilar AA6061-T6 and AA7075-T651 Friction Stir Welds Coupled with Deep Rolling Process |
| title_full_unstemmed | Mechanical Properties Enhancement of Dissimilar AA6061-T6 and AA7075-T651 Friction Stir Welds Coupled with Deep Rolling Process |
| title_short | Mechanical Properties Enhancement of Dissimilar AA6061-T6 and AA7075-T651 Friction Stir Welds Coupled with Deep Rolling Process |
| title_sort | mechanical properties enhancement of dissimilar aa6061 t6 and aa7075 t651 friction stir welds coupled with deep rolling process |
| topic | friction stir welding deep rolling tensile strength residual stress fatigue life |
| url | https://www.mdpi.com/1996-1944/15/18/6275 |
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