**1. Introduction**

The search for improvements in the control of residual stresses resulting from arc welding processes has been intense due to the production requirements imposed by the industrial sector, referring to the fact that stresses affect the mechanical properties of materials, such as strength, plasticity and surface integrity, therefore it is extremely important to measure and evaluate the levels of these stresses in welded joints. The RS exist in structures, parts, components from different manufacturing processes, resulting from interactions of temperature, stresses, and microstructure, which makes its evaluation quite complex. Among the numerous manufacturing processes, the arc welding process generates high levels of RS, formed by the thermal changes imposed. The control of the RS continues from the moment of the conception of the project, passing through the choice of the construction procedures until its completion. There are several ways to measure RS, which can be computational or experimental. During the research of this work it was observed that there is still

no standardized system for the distribution of residual stresses, each author uses what suits him, there is no right or wrong way to observe the RS. But a main point can be considered, being the consensus of many authors is the magnitude of the RS, whether it is compressive or tensile, each type of stress has a specific attribute, which may be beneficial or not for the evaluated component. A methodology worth mentioning for the evaluation of RS is the ultrasonic technique of acoustic birefringence (AB), with this technique it is possible to evaluate a metallic component in a nondestructive and entirety. This line of research, presents an interesting approach, but not much explored. The use of different RS measurement and control technologies, widen the options for existing assessment, with the combination of these technologies it is possible to achieve a reduction in RS levels or even almost its complete elimination. Countless welding processes have been used to control RS. Recently a process has been introduced, the CW-GMAW process (Cold Wire—Gas Metal Arc Welding), showing promising results. The premise of the process is to reduce the temperature of the fusion arc/weld pool. In this context, this work addresses a review of the concepts of residual stresses generated by arc welding, as well as their magnitude and implications for welded structures. However, ways of measuring them are also explored, so that more efficient control methodologies, welding processes are developed, which together with the welding procedures, promote significant results in reducing the values of residual stresses and deformations generated.
