论文标题
使用有限元法的能量解决的中子成像进行应变重建
Energy Resolved Neutron Imaging for Strain Reconstruction using the Finite Element Method
论文作者
论文摘要
脉冲中子成像技术用于从布拉格边缘应变图像中重建多晶材料中的残留应变。该技术提供了对具有较高空间分辨率的应变场进行无损分析的可能性。有限元方法用于使用受平衡条件约束的最小平方方法来重建应变。通过验证悬臂梁问题开发和验证该过程。随后，通过从实验数据中重建菌株的应变来证明，在日本J-PARC的散布中子源读物中测量的环和插头样品。通过与澳大利亚Ansto的Kowari衍射仪上的常规恒定波长应变测量值进行比较来验证重建。还表明，添加简单的Tikhonov正则化可以改善重建。
A pulsed neutron imaging technique is used to reconstruct the residual strain within a polycrystalline material from Bragg edge strain images. This technique offers the possibility of a nondestructive analysis of strain fields with a high spatial resolution. A finite element approach is used to reconstruct the strain using the least square method constrained by the conditions of equilibrium. The procedure is developed and verified by validating for a cantilevered beam problem. It is subsequently demonstrated by reconstructing the strain from experimental data for a ring-and-plug sample, measured at the spallation neutron source RADEN at J-PARC in Japan. The reconstruction is validated by comparison with conventional constant wavelength strain measurements on the KOWARI diffractometer at ANSTO in Australia. It is also shown that the addition of a simple Tikhonov regularization can improve the reconstruction.
