Cumulative Fatigue damage of AA7075-T6 under Shot Peening and Ultrasonic Surface Treatments
One of the important aspects of mechanical design is improving fatigue life.; In this work, the effect of Ultrasonic impact treatment (UIP) and shot peening (SP)on constant cumulative fatigue life and fatigue strength of AA7075-T6 were studied; The sample group was machined and primed, and some spe...
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| Format: | Article |
| Language: | English |
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University of Diyala
2021-03-01
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| Series: | Diyala Journal of Engineering Sciences |
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| Online Access: | https://djes.info/index.php/djes/article/view/801 |
| _version_ | 1811183126158770176 |
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| author | Marwa S. Mahammed Hussain J. Alalkawi Saad T. Faris |
| author_facet | Marwa S. Mahammed Hussain J. Alalkawi Saad T. Faris |
| author_sort | Marwa S. Mahammed |
| collection | DOAJ |
| description |
One of the important aspects of mechanical design is improving fatigue life.; In this work, the effect of Ultrasonic impact treatment (UIP) and shot peening (SP)on constant cumulative fatigue life and fatigue strength of AA7075-T6 were studied; The sample group was machined and primed, and some specimens were treated using ultrasonic impact therapy (UIT) with one line of peening. Fatigue experiments were conducted under constant and variable amplitude (R=-1) at ambient temperature to determine the fatigue life of the S-N curve and fatigue strength during treatment 3.46% and 8.57% at 107 cycles for (UIT) and (SP). Cumulative fatigue damage testing was carried out for two steps loading it is observed that the fatigue life for SP and UIP treated specimens was improved compared to the unpeeled results. The fatigue endurance limit was enhanced by 35% for UIT and 54% for SP. The fatigue life for both treatments was much improved compared to as-received metal. These results also show a strong tendency of increasing fatigue strength after application of (UIT) and (SP) with an increase in mechanical properties of the material used.
Conclusion
• The constant fatigue properties are considerably enhanced by (UIT) and (SP) techniques. The fatigue strength at 107 cycles is improved by 3.46% and 8.57% for UIT and SP respectively.
• Cumulative fatigue life was increased by 13.9 percent and 12.6 percent for low-high and high-low loading by UIT, respectively, while 36.6 percent and 22.3 percent were increased for low-high and high-low loading by SP, respectively, and fatigue life was improved by 36 percent and 54 percent for UIT and SP.
• The (UIT) and (SP) techniques are a suitable method for hardening the surface of metals due to the formation of a hard layer by increasing compressive residual stresses.
• The Miner theory does not follow the conservative and detailed prediction of the life of certain fatigue specimens
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| first_indexed | 2024-04-11T09:42:34Z |
| format | Article |
| id | doaj.art-e5e9547f7b964ebe89098967b5aa09ef |
| institution | Directory Open Access Journal |
| issn | 1999-8716 2616-6909 |
| language | English |
| last_indexed | 2024-04-11T09:42:34Z |
| publishDate | 2021-03-01 |
| publisher | University of Diyala |
| record_format | Article |
| series | Diyala Journal of Engineering Sciences |
| spelling | doaj.art-e5e9547f7b964ebe89098967b5aa09ef2022-12-22T04:31:10ZengUniversity of DiyalaDiyala Journal of Engineering Sciences1999-87162616-69092021-03-0114110.24237/djes.2021.14101Cumulative Fatigue damage of AA7075-T6 under Shot Peening and Ultrasonic Surface TreatmentsMarwa S. Mahammed0Hussain J. Alalkawi1Saad T. Faris2Department of Mechanical Engineering, College of Engineering, University of DiyalaDepartment of Mechanical Engineering, College of Engineering, University of DiyalaDepartment of Mechanical Engineering, College of Engineering, University of Diyala One of the important aspects of mechanical design is improving fatigue life.; In this work, the effect of Ultrasonic impact treatment (UIP) and shot peening (SP)on constant cumulative fatigue life and fatigue strength of AA7075-T6 were studied; The sample group was machined and primed, and some specimens were treated using ultrasonic impact therapy (UIT) with one line of peening. Fatigue experiments were conducted under constant and variable amplitude (R=-1) at ambient temperature to determine the fatigue life of the S-N curve and fatigue strength during treatment 3.46% and 8.57% at 107 cycles for (UIT) and (SP). Cumulative fatigue damage testing was carried out for two steps loading it is observed that the fatigue life for SP and UIP treated specimens was improved compared to the unpeeled results. The fatigue endurance limit was enhanced by 35% for UIT and 54% for SP. The fatigue life for both treatments was much improved compared to as-received metal. These results also show a strong tendency of increasing fatigue strength after application of (UIT) and (SP) with an increase in mechanical properties of the material used. Conclusion • The constant fatigue properties are considerably enhanced by (UIT) and (SP) techniques. The fatigue strength at 107 cycles is improved by 3.46% and 8.57% for UIT and SP respectively. • Cumulative fatigue life was increased by 13.9 percent and 12.6 percent for low-high and high-low loading by UIT, respectively, while 36.6 percent and 22.3 percent were increased for low-high and high-low loading by SP, respectively, and fatigue life was improved by 36 percent and 54 percent for UIT and SP. • The (UIT) and (SP) techniques are a suitable method for hardening the surface of metals due to the formation of a hard layer by increasing compressive residual stresses. • The Miner theory does not follow the conservative and detailed prediction of the life of certain fatigue specimens https://djes.info/index.php/djes/article/view/801AA7075Cumulative fatigue damageUITspLife improving |
| spellingShingle | Marwa S. Mahammed Hussain J. Alalkawi Saad T. Faris Cumulative Fatigue damage of AA7075-T6 under Shot Peening and Ultrasonic Surface Treatments Diyala Journal of Engineering Sciences AA7075 Cumulative fatigue damage UIT sp Life improving |
| title | Cumulative Fatigue damage of AA7075-T6 under Shot Peening and Ultrasonic Surface Treatments |
| title_full | Cumulative Fatigue damage of AA7075-T6 under Shot Peening and Ultrasonic Surface Treatments |
| title_fullStr | Cumulative Fatigue damage of AA7075-T6 under Shot Peening and Ultrasonic Surface Treatments |
| title_full_unstemmed | Cumulative Fatigue damage of AA7075-T6 under Shot Peening and Ultrasonic Surface Treatments |
| title_short | Cumulative Fatigue damage of AA7075-T6 under Shot Peening and Ultrasonic Surface Treatments |
| title_sort | cumulative fatigue damage of aa7075 t6 under shot peening and ultrasonic surface treatments |
| topic | AA7075 Cumulative fatigue damage UIT sp Life improving |
| url | https://djes.info/index.php/djes/article/view/801 |
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