{"title":"Effect of post-treatments on the microstructural and fatigue properties of Ti6Al4V-ELI alloy fabricated by laser powder bed fusion method","authors":"Gürkan Kaya , Fatih Yıldız , Fatih Güler","doi":"10.1016/j.euromechsol.2025.105885","DOIUrl":null,"url":null,"abstract":"<div><div>The Laser Powder Bed Fusion method is a modern production technology that allows products with complex geometry to be produced. In parts produced with this method, surface roughness and defects such as voids and unmelted powders in the internal structure negatively affect the fatigue life of the part. Post-treatments are often needed to optimize the microstructure and obtain the required fatigue properties. This study examined how the mechanical properties were affected by heat treatment (HT) conducted both below and above the <span><math><mi>β</mi></math></span> transformation temperature. The effects of HIP and electropolishing (EP) processes applied to Ti6Al4V-ELI alloys on fatigue behavior were examined. Residual stress values of untreated and post-treated samples were measured, and the results were interpreted. A significant decrease of approximately 10 times in the surface roughness values of fatigue samples was detected with the electropolishing process. The fatigue limit of the as-built (AB) samples was 150 MPa. After applying HT1+EP and HIP+EP post-treatments to the AB samples, the fatigue limit increased by approximately 3.6 and 3.9 times, respectively, compared to the untreated AB condition. Considering the fact that the fatigue limit values between the two groups are not very different and the high cost of the HIP process, it was evaluated that the HT1+EP process may be a more suitable post-treatment in terms of fatigue performance of additively manufactured parts.</div></div>","PeriodicalId":50483,"journal":{"name":"European Journal of Mechanics A-Solids","volume":"116 ","pages":"Article 105885"},"PeriodicalIF":4.2000,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"European Journal of Mechanics A-Solids","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0997753825003195","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MECHANICS","Score":null,"Total":0}
引用次数: 0
Abstract
The Laser Powder Bed Fusion method is a modern production technology that allows products with complex geometry to be produced. In parts produced with this method, surface roughness and defects such as voids and unmelted powders in the internal structure negatively affect the fatigue life of the part. Post-treatments are often needed to optimize the microstructure and obtain the required fatigue properties. This study examined how the mechanical properties were affected by heat treatment (HT) conducted both below and above the transformation temperature. The effects of HIP and electropolishing (EP) processes applied to Ti6Al4V-ELI alloys on fatigue behavior were examined. Residual stress values of untreated and post-treated samples were measured, and the results were interpreted. A significant decrease of approximately 10 times in the surface roughness values of fatigue samples was detected with the electropolishing process. The fatigue limit of the as-built (AB) samples was 150 MPa. After applying HT1+EP and HIP+EP post-treatments to the AB samples, the fatigue limit increased by approximately 3.6 and 3.9 times, respectively, compared to the untreated AB condition. Considering the fact that the fatigue limit values between the two groups are not very different and the high cost of the HIP process, it was evaluated that the HT1+EP process may be a more suitable post-treatment in terms of fatigue performance of additively manufactured parts.
期刊介绍:
The European Journal of Mechanics endash; A/Solids continues to publish articles in English in all areas of Solid Mechanics from the physical and mathematical basis to materials engineering, technological applications and methods of modern computational mechanics, both pure and applied research.