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Multiscale Analysis of Residual Stresses with Novel Non-Destructive and Destructive Approaches using Surface Displacement Measurements

使用表面位移测量通过新颖的非破坏性和破坏性方法进行残余应力的多尺度分析

基本信息

批准号：
1663435
负责人：
Daniel McAdams
金额：
$ 31.89万
依托单位：
Texas A&M Engineering Experiment Station
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-05-01 至 2022-04-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1663435&HistoricalAwards=false
关键词：
Multiscale Analysis Residual Stresses Novel

项目摘要

Engineered materials and parts undergo severe mechanical and thermal loads during their development that result in the formation of internal residual stresses. Residual stresses (nominally force divided by area) are caused by internal forces that remain even after all external loads are removed. Despite the fact that residual stresses can reduce the service life considerably, comprehensive and practical methods to determine them without destroying the parts do not exist. Current non-destructive techniques allow their quantification on the surface of the parts only. Thus, development of new materials or manufacturing techniques can be greatly helped by a thorough estimation of residual stresses that might develop during the processes. For example, residual stresses are extremely prevalent in additively manufactured parts and strongly depend on process parameters in a complex way that are not understood well. This award supports fundamental research in inverse computational methods based on the mechanics of materials to estimate residual stresses in both non-destructive and destructive fashions from the measurement of forces and surface displacements. Advancement in residual stress analysis will promote both opportunistic use and mitigation in the development of new materials and manufacturing processes, which will greatly enhance automotive, aerospace, defense, and nuclear industries. The research team will also promote engineering and education through participation in the summer camp programs that will involve female and underrepresented high school students.For the development of the non-destructive approach, surface displacements will be measured cost-effectively on varying part sizes using digital camera images to trace speckle patterns. Mechanics-based mathematical algorithms derived using adjoint equations will be implemented to infer residual stress distribution from these measurements. Validation on a 3D printed rubber like material will be conducted. For the development of the destructive approach, very thin sectioned samples will be retrieved from the polycrystalline specimens to relieve all residual stresses, with the implication that the thin slices will deform as a result. Subsequent loadings of the samples will be used to determine the heterogeneous, anisotropic granular microstructure of the material using mechanics-based mathematical models. Application of reverse deformation on the now known microstructure to retrieve the original configuration can then be used to predict the residual stresses in the given section of the material. The fundamental scientific issue underlying both approaches is: What are the minimum number of experimental data sets and deformation modes, i.e., experiments, required to uniquely map residual stresses?

工程材料和零件在其开发过程中会承受严重的机械和热负荷，从而导致内部残余应力的形成。残余应力（名义上的力除以面积）是由内力引起的，即使在所有外部载荷被移除后仍然存在。尽管残余应力会显著降低使用寿命，但不存在在不破坏零件的情况下确定残余应力的全面实用的方法。目前的非破坏性技术只允许在零件表面进行量化。因此，新材料或制造技术的开发可以通过对工艺过程中可能产生的残余应力进行彻底的估计来大大帮助。例如，残余应力在增材制造零件中极其普遍，并且以一种尚不清楚的复杂方式强烈依赖于工艺参数。该奖项支持基于材料力学的逆计算方法的基础研究，以通过力和表面位移的测量以非破坏性和破坏性方式估计残余应力。残余应力分析的进步将促进新材料和制造工艺开发中的机会性使用和缓解，这将大大增强汽车，航空航天，国防和核工业。研究小组还将通过参加夏令营项目来促进工程和教育，这些夏令营项目将涉及女性和代表性不足的高中生。为了开发非破坏性方法，将使用数码相机图像跟踪散斑图案，在不同尺寸的零件上以具有成本效益的方式测量表面位移。使用伴随方程推导出的基于力学的数学算法将被实现，以从这些测量结果推断出残余应力分布。将对3D打印的橡胶类材料进行验证。对于破坏性方法的开发，将从多晶试样中取出非常薄的切片样品，以释放所有残余应力，这意味着薄片将因此变形。随后的样品加载将用于使用基于力学的数学模型来确定材料的非均质、各向异性颗粒微观结构。在已知的微结构上施加反向变形以恢复原始结构，然后可以用于预测材料的给定截面中的残余应力。这两种方法背后的基本科学问题是：实验数据集和变形模式的最小数量是多少，即，实验，需要独特的地图残余应力？

项目成果

期刊论文数量（6）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Identification of Material Parameters of a Hyper-Elastic Body With Unknown Boundary Conditions

DOI：
10.1115/1.4039170
发表时间：
2018-02
期刊：
Journal of Applied Mechanics
影响因子：
0
作者：
M. Hajhashemkhani;M. Hematiyan;S. Goenezen
通讯作者：
M. Hajhashemkhani;M. Hematiyan;S. Goenezen

A comparative study of two constitutive models within an inverse approach to determine the spatial stiffness distribution in soft materials

DOI：
10.1016/j.ijmecsci.2018.03.004
发表时间：
2018-05-01
期刊：
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
影响因子：
7.3
作者：
Mei, Y.;Stover, B.;Goenezen, S.
通讯作者：
Goenezen, S.

Characterization of the stiffness distribution in two and three dimensions using boundary deformations: a preliminary study

使用边界变形表征二维和三维刚度分布：初步研究

DOI：
10.1557/mrc.2018.98
发表时间：
2018
期刊：
MRS Communications
影响因子：
1.9
作者：
Luo, Ping;Mei, Yue;Kotecha, Maulik;Abbasszadehrad, Amirhossein;Rabke, Stephen;Garner, Geoffrey;Goenezen, Sevan
通讯作者：
Goenezen, Sevan

Mechanics Based Tomography (MBT): Validation using experimental data