Fatigue Properties of AZ31B Magnesium Alloy Processed by Equal-Channel Angular Pressing
A stent is employed to expand a narrowed tubular organ, such as a blood vessel. However, the persistent presence of a stainless steel stent yields several problems of late thrombosis, restenosis and chronic inflammation reactions. Biodegradable magnesium stents have been introduced to solve these pr...
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| Format: | Article |
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MDPI AG
2021-07-01
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| Series: | Metals |
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| Online Access: | https://www.mdpi.com/2075-4701/11/8/1191 |
| _version_ | 1797522957804765184 |
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| author | Ryuichi Yamada Shoichiro Yoshihara Yasumi Ito |
| author_facet | Ryuichi Yamada Shoichiro Yoshihara Yasumi Ito |
| author_sort | Ryuichi Yamada |
| collection | DOAJ |
| description | A stent is employed to expand a narrowed tubular organ, such as a blood vessel. However, the persistent presence of a stainless steel stent yields several problems of late thrombosis, restenosis and chronic inflammation reactions. Biodegradable magnesium stents have been introduced to solve these problems. However, magnesium-based alloys suffer from poor ductility and lower than desired fatigue performance. There is still a huge demand for further research on new alloys and stent designs. Then, as fundamental research for this, AZ31 B magnesium alloy has been investigated for the effect of equal-channel angular pressing on the fatigue properties. ECAP was conducted for one pass and eight passes at 300 °C using a die with a channel angle of 90°. An annealed sample and ECAP sample of AZ31 B magnesium alloy were subjected to tensile and fatigue tests. As a result of the tensile test, strength in the ECAP (one pass) sample was higher than in the annealed sample. As a result of the fatigue test, at stress amplitude <i>σ<sub>a</sub></i> = 100 MPa, the number of cycles to failure was largest in the annealed sample, medium in the ECAP (one pass) sample and lowest in the ECAP (eight passes) sample. It was suggested that the small low cycle fatigue life of the ECAP (eight passes) sample is attributable to severe plastic deformation. |
| first_indexed | 2024-03-10T08:36:41Z |
| format | Article |
| id | doaj.art-fdc94d15972c4c689f7db0da365fc43c |
| institution | Directory Open Access Journal |
| issn | 2075-4701 |
| language | English |
| last_indexed | 2024-03-10T08:36:41Z |
| publishDate | 2021-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Metals |
| spelling | doaj.art-fdc94d15972c4c689f7db0da365fc43c2023-11-22T08:40:48ZengMDPI AGMetals2075-47012021-07-01118119110.3390/met11081191Fatigue Properties of AZ31B Magnesium Alloy Processed by Equal-Channel Angular PressingRyuichi Yamada0Shoichiro Yoshihara1Yasumi Ito2Graduate Faculty of Interdisciplinary Research Faculty of Engineering, Mechanical Engineering (Mechanical Engineering), University of Yamanashi, 4-3-11 Takeda, Kofu-shi 400-8511, JapanDepartment of Engineering and Design, Shibaura Institute of Technology, 3-9-14 Minato-ku, Tokyo 108-8548, JapanGraduate Faculty of Interdisciplinary Research Faculty of Engineering, Mechanical Engineering (Mechanical Engineering), University of Yamanashi, 4-3-11 Takeda, Kofu-shi 400-8511, JapanA stent is employed to expand a narrowed tubular organ, such as a blood vessel. However, the persistent presence of a stainless steel stent yields several problems of late thrombosis, restenosis and chronic inflammation reactions. Biodegradable magnesium stents have been introduced to solve these problems. However, magnesium-based alloys suffer from poor ductility and lower than desired fatigue performance. There is still a huge demand for further research on new alloys and stent designs. Then, as fundamental research for this, AZ31 B magnesium alloy has been investigated for the effect of equal-channel angular pressing on the fatigue properties. ECAP was conducted for one pass and eight passes at 300 °C using a die with a channel angle of 90°. An annealed sample and ECAP sample of AZ31 B magnesium alloy were subjected to tensile and fatigue tests. As a result of the tensile test, strength in the ECAP (one pass) sample was higher than in the annealed sample. As a result of the fatigue test, at stress amplitude <i>σ<sub>a</sub></i> = 100 MPa, the number of cycles to failure was largest in the annealed sample, medium in the ECAP (one pass) sample and lowest in the ECAP (eight passes) sample. It was suggested that the small low cycle fatigue life of the ECAP (eight passes) sample is attributable to severe plastic deformation.https://www.mdpi.com/2075-4701/11/8/1191magnesium alloyfatigueequal-channel angular pressinggrain refinementS–N curvestent |
| spellingShingle | Ryuichi Yamada Shoichiro Yoshihara Yasumi Ito Fatigue Properties of AZ31B Magnesium Alloy Processed by Equal-Channel Angular Pressing Metals magnesium alloy fatigue equal-channel angular pressing grain refinement S–N curve stent |
| title | Fatigue Properties of AZ31B Magnesium Alloy Processed by Equal-Channel Angular Pressing |
| title_full | Fatigue Properties of AZ31B Magnesium Alloy Processed by Equal-Channel Angular Pressing |
| title_fullStr | Fatigue Properties of AZ31B Magnesium Alloy Processed by Equal-Channel Angular Pressing |
| title_full_unstemmed | Fatigue Properties of AZ31B Magnesium Alloy Processed by Equal-Channel Angular Pressing |
| title_short | Fatigue Properties of AZ31B Magnesium Alloy Processed by Equal-Channel Angular Pressing |
| title_sort | fatigue properties of az31b magnesium alloy processed by equal channel angular pressing |
| topic | magnesium alloy fatigue equal-channel angular pressing grain refinement S–N curve stent |
| url | https://www.mdpi.com/2075-4701/11/8/1191 |
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