Non-Destructive Measurement of Residual Stress by Magnetostriction Effect : In the Case of Measurement by Shear Difference Method

The non-destructive analysis by GIXRD allows us to determine the residual stress distribution as a function of XRD penetration depth and film thickness. A new development on the determination of residual stresses distribution is presented here. The procedure, based on the GIXRD geometry (referred to here as the ‘sin2ψ*’), enables non-destructive measurement of stresses gradient with only one diffraction family plan at a chosen depth taking into account the correction of measured direction. The chosen penetration depth is well defined for different combination of ψ and Φ and needs not to be changed during experimentation. This method was applied for measurement of residual stress gradient in Cu thin films. The obtained residual stress levels and their distribution were quite comparable with those determined by another multi-reflection method.

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Residual stress management: Recent advances in engineering methods for non-destructive measurement and beneficial redistribution of residual stresses

Zavarivanje i zavarene konstrukcije ◽

10.5937/zzk2102083k ◽

2021 ◽

Vol 66 (2) ◽

pp. 83-95

Author(s):

Jacob Kleiman

Keyword(s):

Residual Stress ◽

Fatigue Life ◽

Residual Stresses ◽

Stress Management ◽

Stress Measurement ◽

Fatigue Behavior ◽

Engineering Properties ◽

Practical Engineering ◽

Destructive Measurement ◽

Non Destructive

Welding is used widely in the automotive industry for joining a variety of structural components and parts. Of paramount importance in these structures are their engineering properties, such as fatigue life, distortions, dimensional stability and corrosion resistance that can be affected considerably by the presence of residual stresses (RS). The knowledge of RS and the ability to control their distribution in welded structures is critical when evaluating their fatigue life and preventing catastrophic failures. An engineering concept of residual stress management (RSM) has been developed that addresses all aspects of residual stresses in structural elements. RSM includes three major stages in stress management, i.e. RS determination, RS analysis and RS redistribution. Using this approach, stresses in structures and materials can be evaluated in each specific case either theoretically or experimentally and the performance and fatigue behavior of such structures optimized. This paper is built as an overview of the RSM concept and its application in the fields of non-destructive measurement of residual and applied stresses and in treatment of structures with residual stresses to achieve better performance and longer fatigue life. All three stages of the RSM concept will be discussed and for each of the stages practical engineering approach examples will be given. An example of a project in which the residual stress distribution in a filet welded joint was measured, analyzed and changed by post-weld treatment will be presented to demonstrate the effectiveness of the RSM approach. The advancements in the modern tools used in this project for non-destructive measurement of residual stresses using an ultrasonic computerized complex for residual stress measurement and the ultrasonic peening for redistribution of the residual stresses that allowed improving the quality of the welds and increasing their fatigue life will also be presented.

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