INFLUÊNCIA DO TIPO DE ALIMENTAÇÃO DO PROCESSO GTAW AUTOMÁTICO SOBRE A MICROESTRUTURA DO AÇO SAE 1020

Abstract

The GTAW (Gas Tungsten Arc Welding) process is widely recognized for its high metallurgical quality and the thermal control it provides. With the evolution of filler material feeding systems, variations have emerged such as continuous feeding (C-GTAW) and dynamic wire feeding (GTAW-DWF), which introduces controlled dynamics in the wire supply. This study is based on the doctoral thesis by Neves (2022), which investigated the influence of dynamic feed frequency in the automatic GTAW process, highlighting significant differences between continuous (C-GTAW) and dynamic (GTAW-DWF) feed modes; therefore, this work presents a technical comparison between both processes, focusing on the microstructural analysis of the molten zone. Aspects such as cooling rate, grain morphology, dilution, arc stability, and influence on thermal control are discussed. The results indicate that the GTAW-DWF process provides superior microstructural refinement and greater control of heat input, contributing to better mechanical properties and process repeatability.