Residual stresses in cold-wire gas metal arc welding

Abstract

This work compares the welding residual stresses of the cold-wire gas metal arc welding and conventional gas metal arc welding processes. Two techniques were used to measure the residual stresses: X-ray diffraction and acoustic birefringence. The base metal used was carbon manganese steel plates of 9.5-mm thickness. The results showed that the introduction of the cold-wire tends to decrease the residual stresses, suggesting that the introduction of the cold wire decreases the amount of heat given to the base metal, and consequently lowers residual stresses.

X-Ray Diffraction Analysis of Residual Stresses in the Premium Rails Welded by Flash Butt Process

“…The propagation area of residual stress measurement was 7.0 mm 2 on each measured point, due to the X-ray beam (3 mm in diameter). The accuracy of residual stress measurements was ± 20 MPa [15, 16,28].…”

“…Given the measurements made in the top of the rail, Figure 4a together with the measurements made in the lateral of the top of the rail, Figure 4b it can be plotted, using Autodesk and Autocad Software, a representation of the distribution of residual stresses along the entire surface of the top of the rail. This representation is made through the projection of the values presented in the referred Figures and subsequent filling the missing stresses through the gradient values that complete the gaps of stresses [16]. This representation is presented in Figure 5 showing the surface map of the top of the rail, which arises from an interpolation of all the measurements previously made in the region of top of the rail [16].…”

“…Tensile forces are conducive to shear and can lead the material to rupture, compressive forces tend to compress a body applying pressure [16,17]. These stresses are generally imputed into the material after it passes through thermal and / or mechanical processes [16][17][18]. Some examples of processes that may add residual stresses in rails are: casting, rolling, forging, welding, machining, bending, pressing, straightening and heat treatments.…”

“…Nowadays, the methodologies applied to measure residual stress in rails require destructive (rail web sawing), semi destructive (blind hole test), laboratory techniques (strain gauges), being necessary to remove samples off the track and sending to laboratories. This paper differentiation is to pursue a non-destructive test technology [16,17,19] for the residual stress measurement, so technology could be applied on field (on track), thus the selected technology was the X-ray diffraction.…”

Numerical prediction and experimental validation of temperature and residual stress distributions in buried‐arc welded thick plates

“…Deng et al presented an investigation where a computational approach was based on a finite element method, which considered both material nonlinearity and geometrical nonlinearity and was developed to investigate the welding distortion and residual stress in low carbon steel thin‐plate bead‐on joints induced by welding, and the obtained results were verified experimentally. Costa et al compared the welding‐induced residual stresses of the cold‐wire and conventional MAG welding processes by using X‐ray diffraction and acoustic birefringence in their experimental study. Kung et al proposed a novel method for analyzing residual stresses and deformations in butt‐welded thin stainless plates using a numerical method to find the best location for jig fixtures that would minimize welding deformation.…”