Crack Growth of Defects in Ti-6Al-4V Under Uniaxial Tension: Measurements and Modeling

IF 2 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics Pub Date : 2023-11-21 DOI:10.1007/s11340-023-01008-y

E.T. Furton, A. M. Beese

{"title":"Crack Growth of Defects in Ti-6Al-4V Under Uniaxial Tension: Measurements and Modeling","authors":"E.T. Furton, A. M. Beese","doi":"10.1007/s11340-023-01008-y","DOIUrl":null,"url":null,"abstract":"<div><h3>Background</h3><p>This study investigates the effects of pores on the mechanical properties of metals produced by additive manufacturing, which can limit strength and ductility.</p><h3>Objective</h3><p>This research aims to both measure and model the rate of crack growth emanating from these pores in additively manufactured Ti-6Al-4 V fabricated with laser powder bed fusion.</p><h3>Methods</h3><p>Uniaxial tensile samples containing intentionally embedded penny-shaped pores were mechanically tested to failure, and loading was interrupted by a series of unload steps to measure the stiffness degradation with load. The factors contributing to reduction in stiffness, namely (1) elastic and plastic changes to geometry, (2) the effect of plastic deformation on modulus, and (3) crack growth, were deconvoluted through finite element modeling, and the crack size was estimated at each unloading step.</p><h3>Results</h3><p>The stiffness-based method was able to detect stable crack growth in samples with large pores (1.6% to 11% of the cross-sectional area). Crack growth as a function of strain was fit to a model where the crack driving force was based on equivalent strain and a model where the crack driving force was based on energy release rate.</p><h3>Conclusions</h3><p>Significant crack growth occurred only after the onset of necking in samples containing small pores, while samples containing large pores experienced continuous crack growth with strain.</p><h3>Graphical Abstract</h3>\n<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":552,"journal":{"name":"Experimental Mechanics","volume":null,"pages":null},"PeriodicalIF":2.0000,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Experimental Mechanics","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s11340-023-01008-y","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, CHARACTERIZATION & TESTING","Score":null,"Total":0}

引用次数: 0

Abstract

Background

This study investigates the effects of pores on the mechanical properties of metals produced by additive manufacturing, which can limit strength and ductility.

Objective

This research aims to both measure and model the rate of crack growth emanating from these pores in additively manufactured Ti-6Al-4 V fabricated with laser powder bed fusion.

Methods

Uniaxial tensile samples containing intentionally embedded penny-shaped pores were mechanically tested to failure, and loading was interrupted by a series of unload steps to measure the stiffness degradation with load. The factors contributing to reduction in stiffness, namely (1) elastic and plastic changes to geometry, (2) the effect of plastic deformation on modulus, and (3) crack growth, were deconvoluted through finite element modeling, and the crack size was estimated at each unloading step.

Results

The stiffness-based method was able to detect stable crack growth in samples with large pores (1.6% to 11% of the cross-sectional area). Crack growth as a function of strain was fit to a model where the crack driving force was based on equivalent strain and a model where the crack driving force was based on energy release rate.

Conclusions

Significant crack growth occurred only after the onset of necking in samples containing small pores, while samples containing large pores experienced continuous crack growth with strain.

Graphical Abstract

Abstract Image

查看原文本刊更多论文

Ti-6Al-4V缺陷在单轴拉伸下的裂纹扩展:测量与建模

本研究探讨了孔隙对增材制造金属力学性能的影响，这些孔隙会限制金属的强度和延展性。目的对激光粉末床熔合增材制备ti - 6al - 4v材料的裂纹扩展速率进行测量和建模。方法对单轴拉伸试样进行有意嵌入便士形孔隙的力学试验直至破坏，并通过一系列卸载步骤中断加载，测量其刚度随载荷的退化情况。通过有限元建模对导致刚度降低的因素(1)弹塑性几何变化、(2)塑性变形对模量的影响、(3)裂纹扩展进行反卷积，并对各卸载步骤的裂纹尺寸进行估计。结果基于刚度的方法能够检测到大孔隙(占截面积的1.6% ~ 11%)试样的稳定裂纹扩展。裂纹扩展作为应变的函数符合裂纹驱动力基于等效应变的模型和裂纹驱动力基于能量释放率的模型。结论孔隙小的试样只有在颈缩开始后才会出现明显的裂纹扩展，而孔隙大的试样则随着应变的变化出现连续的裂纹扩展。图形抽象

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

Experimental Mechanics 物理-材料科学：表征与测试

CiteScore

4.40

自引率

16.70%

发文量

111

审稿时长

3 months

期刊介绍： Experimental Mechanics is the official journal of the Society for Experimental Mechanics that publishes papers in all areas of experimentation including its theoretical and computational analysis. The journal covers research in design and implementation of novel or improved experiments to characterize materials, structures and systems. Articles extending the frontiers of experimental mechanics at large and small scales are particularly welcome. Coverage extends from research in solid and fluids mechanics to fields at the intersection of disciplines including physics, chemistry and biology. Development of new devices and technologies for metrology applications in a wide range of industrial sectors (e.g., manufacturing, high-performance materials, aerospace, information technology, medicine, energy and environmental technologies) is also covered.