Non-destructive estimation of three-dimensional welding residual stresses by using X-ray diffraction

2016 Fiscal Year Final Research Report

• Project/Area Number: 26820005
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Materials/Mechanics of materials
• Research Institution: Yokohama National University
• Principal Investigator: Ogawa Masaru 横浜国立大学, 大学院工学研究院, 助教 (90635236)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 逆問題 / 非破壊 / 残留応力 / X線回折 / 固有ひずみ / 溶接 / 有限要素法

Outline of Final Research Achievements

A nondestructive method to evaluate three-dimensional residual stresses by using X-ray diffraction and the eigenstrain methodology has been proposed. This method makes it possible to estimate three-dimensional residual stresses on-site without neutron diffraction.
This study aims to evaluate the effectiveness of this method for actual welded joints. The estimation accuracy of this method has been evaluated for ferritic welded plates and friction stir welded joint. Residual stresses, especially on a welded plate jointed by automatic welding system, could be estimated with higher accuracy. When heat source is oscillated during welding, inelastic strains, as a source of residual stresses, are intricately distributed.

Free Research Field

機械材料・材料力学