A novel methodology for estimating tensile properties in a small punch test employing in-situ DIC based deflection mapping
A novel methodology for estimating tensile properties in a small punch test employing in-situ DIC based deflection mapping
复制标题
DOI：
10.1016/j.jnucmat.2020.152260
复制
发表时间：
2020-09
影响因子：
3.1
通讯作者：
V. Vijayanand;M. Mokhtarishirazabad;J. Peng;Yiqiang Wang;M. Gorley;David A. Knowles;M. Mostafavi
中科院分区：
文献类型：
--
作者：
V. Vijayanand;M. Mokhtarishirazabad;J. Peng;Yiqiang Wang;M. Gorley;David A. Knowles;M. Mostafavi
在核工业中，由于与标准试验相比，小冲杆试验使用的材料体积有限，因此在考虑活性或开发样品时，小冲杆试验确定拉伸性能是至关重要的。在利用这种技术的全部潜力的关键挑战之一是制定相关的小冲孔试样的偏转等效单轴拉伸性能的方法。现有的相关方法依赖于从小冲杆试样上的单个点获得的挠度，并与经验方程一起使用以进行相关。然而，在一个小冲孔试样的挠度和应变积累是高度不均匀的，从一个单一的点的数据并不代表总变形演变的试样。该数据与经验公式结合使用时，推导出等效的单轴拉伸性能，将不会导致材料性能的准确识别。在这项工作中，我们提供了一种替代方法，它使用全场偏转的标本映射通过原位数字图像相关。结合逆有限元分析的数字图像相关的使用增强了从单点挠度数据识别材料特性的现有方法，从而显着提高测量的可靠性。
Determining tensile properties from small punch test is being pursued actively in the nuclear industry due to the limited volume of material such tests use compared with standard tests which can be critical when considering active or development samples. One of the crucial challenges in harnessing the full potential of this technique is formulating methodologies which correlate the small punch specimen’s deflection to equivalent uniaxial tensile properties. Existing approaches for correlation rely on deflection obtained from a single point on the small punch test specimen, used with empirical equations to make the correlation. However, the deflection and strain accumulation in a small punch specimen is highly heterogeneous and data from a single point does not represent the gross deformation evolving in the specimen. This data when used in conjunction with the empirical formulations for deriving equivalent uniaxial tensile properties, would not result in accurate identification of material properties. In this work we offer an alternative approach which uses the full field deflection of the specimen mapped through in-situ digital image correlation. The use of digital image correlation combined with inverse finite element analysis augments the existing method of material properties identification from single point deflection data thereby significantly improving the reliability of the measurements.