Effect of heat treatment on fatigue life and accuracy of incrementally formed AA2024

IF 2 Q3 ENGINEERING, MANUFACTURING

Manufacturing Letters Pub Date : 2025-08-01 DOI:10.1016/j.mfglet.2025.06.037

K. Praveen , N. Venkata Reddy

{"title":"Effect of heat treatment on fatigue life and accuracy of incrementally formed AA2024","authors":"K. Praveen , N. Venkata Reddy","doi":"10.1016/j.mfglet.2025.06.037","DOIUrl":null,"url":null,"abstract":"<div><div>Double-sided incremental forming (DSIF) gaining importance in shaping 3D sheet metal components without relying on geometric-specific tooling. The challenge persists in forming high-work hardening aerospace aluminium alloys (AA2xxx) with better properties (tensile and fatigue) along with accuracy. The amount of spring-back for the AA2xxx is more especially when deformation is carried out using a tempered sheet compared to an annealed one. In contrast, the strength of an annealed sheet will be less compared to a tempered one. In the present work, an experimental work is carried out to study the effect of heat treatment (solution treatment–quenching–aging) on the tensile and fatigue properties of components formed using annealed sheets, along with the dimensional deviations that occur during heat treatment compared to the DSIF formed part. Various geometries (pyramid, cone, free-form) are formed using annealed (AA2024-O) sheets followed by heat treatment (HT, to attain AA2024-T62). Results show that the fatigue life of specimens extracted from DSIF components before HT is significantly lower than that of the as-received material. This reduction is due to decreased uniform elongation. However, after heat treatment, the fatigue life of specimens extracted from DSIF components increased compared to the as-received material before HT. This improvement is attributed to the precipitation of fine second-phase particles. These particles impede dislocation motion, enhancing fatigue life under given strain amplitudes. For the geometries formed in present work, the maximum dimensional deviations from intended geometry before heat treatment ranged from −0.43 mm to −0.59 mm, (where the negative values indicate under forming). After heat treatment of components, measurements were carried out again, and it is observed that an increase in dimensional deviations (i.e., varied from −0.52 mm to −0.64 mm) with difference in magnitude less than 150 µm compared to initially formed DSIF part. This indicates that the warpage due to rapid quenching is minimal.</div></div>","PeriodicalId":38186,"journal":{"name":"Manufacturing Letters","volume":"44 ","pages":"Pages 306-313"},"PeriodicalIF":2.0000,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Manufacturing Letters","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2213846325000690","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENGINEERING, MANUFACTURING","Score":null,"Total":0}

引用次数: 0

Abstract

Double-sided incremental forming (DSIF) gaining importance in shaping 3D sheet metal components without relying on geometric-specific tooling. The challenge persists in forming high-work hardening aerospace aluminium alloys (AA2xxx) with better properties (tensile and fatigue) along with accuracy. The amount of spring-back for the AA2xxx is more especially when deformation is carried out using a tempered sheet compared to an annealed one. In contrast, the strength of an annealed sheet will be less compared to a tempered one. In the present work, an experimental work is carried out to study the effect of heat treatment (solution treatment–quenching–aging) on the tensile and fatigue properties of components formed using annealed sheets, along with the dimensional deviations that occur during heat treatment compared to the DSIF formed part. Various geometries (pyramid, cone, free-form) are formed using annealed (AA2024-O) sheets followed by heat treatment (HT, to attain AA2024-T62). Results show that the fatigue life of specimens extracted from DSIF components before HT is significantly lower than that of the as-received material. This reduction is due to decreased uniform elongation. However, after heat treatment, the fatigue life of specimens extracted from DSIF components increased compared to the as-received material before HT. This improvement is attributed to the precipitation of fine second-phase particles. These particles impede dislocation motion, enhancing fatigue life under given strain amplitudes. For the geometries formed in present work, the maximum dimensional deviations from intended geometry before heat treatment ranged from −0.43 mm to −0.59 mm, (where the negative values indicate under forming). After heat treatment of components, measurements were carried out again, and it is observed that an increase in dimensional deviations (i.e., varied from −0.52 mm to −0.64 mm) with difference in magnitude less than 150 µm compared to initially formed DSIF part. This indicates that the warpage due to rapid quenching is minimal.

查看原文本刊更多论文

热处理对增量成形AA2024疲劳寿命和精度的影响

双面增量成形（DSIF）在不依赖于几何特定工具的情况下，在塑造3D钣金部件方面变得越来越重要。在制造高加工硬化航空铝合金（AA2xxx）方面仍然存在挑战，该合金具有更好的性能（拉伸和疲劳）以及精度。与退火板相比，回火板进行变形时，AA2xxx的回弹量更多。相反，退火板的强度将低于回火板。在目前的工作中，进行了一项实验工作，研究热处理（固溶处理-淬火-时效）对使用退火板形成的部件的拉伸和疲劳性能的影响，以及与DSIF形成的部件相比，热处理过程中发生的尺寸偏差。使用退火（AA2024-O）板材，然后进行热处理（HT），以获得AA2024-T62，形成各种几何形状（金字塔，锥体，自由形状）。结果表明，高温处理前提取的DSIF构件疲劳寿命明显低于接收材料的疲劳寿命。这种降低是由于均匀伸长率降低。然而，热处理后，从DSIF构件中提取的试样的疲劳寿命比热处理前的接收材料有所增加。这种改善是由于细小的第二相颗粒的析出。这些颗粒阻碍了位错运动，提高了给定应变幅值下的疲劳寿命。对于目前工作中形成的几何形状，热处理前与预期几何形状的最大尺寸偏差范围为- 0.43 mm至- 0.59 mm（其中负值表示成形过程）。在对部件进行热处理后，再次进行测量，可以观察到尺寸偏差的增加（即从- 0.52 mm到- 0.64 mm），与最初形成的DSIF部件相比，差异小于150 µm。这表明由于快速淬火引起的翘曲是最小的。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊