Effect of Residual Stress on Thermal Deformation Behavior

Abstract

This paper discusses a non-destructive measurement technique of residual stress through optical visualization. The least amount of deformation possible is applied to steel plates by heating the specimens +10 °C from room temperature for initial calibration, and the thermal expansion behavior is visualized with an electronic speckle pattern interferometer sensitive to two dimensional in-plane displacement. Displacement distribution with the thermal deformation and coefficient of thermal expansion are obtained through interferometric fringe analysis. The results suggest the change in the thermal deformation behavior is affected by the external stress initially applied to the steel specimen. Additionally, dissimilar joints of steel and cemented carbide plates are prepared by butt-brazing. The residual stress is estimated based on the stress dependence of thermal expansion coefficient.

Study of the Contact Thermal Compression Behavior of Copper using Scanning Contact Potentiometry Method and Finite Element Analysis

“…The presence of residual stresses is temperature-dependent and is due to the effective coefficients of thermal expansion being significantly different along with different specimen directions. Subsequently, thermal expansion between different constituent materials lead to changes in thermal residual stresses, affecting the strength and integrity of the welded copper specimen under test, [41] this is most significant at the weld zone of dissimilar metals, where high residual stresses have been induced lead to degradation in the integrity of the joint [42]. SCP results are also presented using potentiograms shown in Figure 9 Potentiograms show the distribution of the electrical potential difference across the specimen's surface gauge area, measured in 10 (Y-axis) tracks with a duration of 271 s scanning time (X axis), meaning a scanning length of 89 mm for each track.…”

Advances in Multi-Scale Mechanical Characterization of Materials with Optical Methods

“…The determination of residual stress with optical methods (i.e., ESPI and digital image correlation) is discussed in Refs. [ 7 , 8 ]. In particular, Sasaki et al [ 7 ] evaluated changes in elastic modulus caused by residual stresses.…”

“…[ 7 , 8 ]. In particular, Sasaki et al [ 7 ] evaluated changes in elastic modulus caused by residual stresses. Compressive or tensile residual stress should, respectively, increase or decrease elastic modulus.…”