Application of Digital Image Correlation for Comparison of Deformation Response in Fusion and Friction Stir Welds

Abstract

The deformation response of welded aluminum plate was evaluated at high and low strain rates. Mechanical and ballistic experiments were conducted on 2.5 cm thick samples obtained from full penetration welds for welded aluminum 5083-H131 plate. Similar experiments were also conducted for the aluminum 5083 alloy as a baseline for comparison. Experiments were designed to compare the deformation response and ballistic performance differences for fusion welds versus friction stir welds. The fusion welds were processed using gas metal arc welding. The low strain rate deformation response was evaluated with three-point bend tests at an approximate strain rate of 1 s-1. The high strain rate response of the three materials was assessed using ballistic impact experiments at a range of velocities. Digital image correlation analysis was applied to gain insight into the deformation response through quantification of the strain and deflection profiles. The deformation response differences are compared for the welds versus the baseline aluminum alloy.

Calculation-experimental procedure for determining welding deformations and stresses based on a digital image correlation method

“…To determine the stressed state, the method of digital image correlation (DIC) is increasingly used [9,10]. This method has been developed by significantly increasing the quality and reducing the cost of digital cameras, as well as increasing the speed of computer technology.…”

“…Its action is based on the calculation of motion vectors and further calculation of deformation components using the numerical differentiation procedure [11]. The main advantages of DIC method are a sufficiently high accuracy associated with the resolution of the digital cameras used, as well as the absence of impact on the measured structure [10,11]. The use of this method is becoming one of the most common approaches to the study of the processes of deformation and destruction of structurally inhomogeneous materials.…”

A Study on Tensile Strain Distribution and Fracture Coordinate of Nanofiber Mat by Digital Image Correlation System

“…Two more equations can be adopted for each criterion by averaging or There are two methods to analyze the image correlation: one is to use the cross-correlation (CC) criterion, and the other is to apply the sum of squared differences (SSD) criterion. These methods measure the brightness values of spots on the image for analysis [18,19]. The CC criterion uses the maximum value of the highest correlation from the calculation.…”

“…Figure19. Comparison between the Y-direction strain measurement result with the highest strain (left) and the fracture position of specimen (right: black-and-white reversed image).…”

Comparative analysis of experimental and numerical investigation on multiple projectile impact of AA5083 friction stir welded targets

“…The ballistic behaviour of GMAW and friction stir welded AA5083 thin sheets was investigated by Dannemann et al [ 13 ]. They found the less ballistic performance and more damage was observed in the GMAW joints as compared to FSW joints.…”