Estudio y Análisis Microestructural del Proceso Acelerado del Proceso de Corrosión Presentado en Tuberías de Acero Dúplex 2205 Soldadas Mediante Proceso GTAW

Abstract

This research studied the changes in the microstructure, physical characteristics and mechanical properties of the pipe duplex stainless steel 2205 welded by GTAW process, when subjected to an accelerated process of corrosion under the application of constant loads on the specimens, being a complementary work, the welding is obtained from an already generated WPS. The test pieces subjected to the corrosion test, show changes of coloration on its surface and variation of mass, in the macrographs is evident the ferritic and austenitic phases of the steel in form of elongated grains, characteristic of the steel hot rolled, addition in the micrographs is observe detachment of material characteristic of uniform corrosion and pitting corrosion, as well as the emergence of intermetallic phases, inclusions, and nucleation of the grain in ellipsoidal and Windmastatten forms by the heat generated in the welding process. Another aspect analyzed was the hardness in HV and HRC, obtaining values below the ASTM A790 standard, which presents the specifications of stainless steels, results that show that the mechanical properties were affected by the corrosion process. By scanning electron microscopy (SEM) is revealed the distribution of the alloys present in a point, demonstrating the presence of the primordial elements that make up the duplex stainless steel.