Eventos Anais de eventos
COBEF 2017
Congresso Brasileiro de Engenharia de Fabricação
HYDROGEN CRACK RESEARCH IN WELDED JOINTS WITH ACOUSTIC EMISSION AND IMPLANT TEST
Submission Author:
roberta adrielle vieira , MA
Co-Authors:
Waldemir Passos Martins, Valdemar Leal, Antonio Paiva, Victor Hugo Barbosa Santos
Presenter: roberta adrielle vieira
doi://10.26678/ABCM.COBEF2017.COF2017-0112
Abstract
There were an increase in the need for steel which is used to transport fluids such as oil and natural gas due to the discovery of new reserves in harsh environments and reserves distant from consumption centers, so it enhanced progressively the demand for high- strength steels and lower costs. Therefore, HSLA steels (high strength, low alloy) have been used because of its good weldability, mechanical strength and lower cost due to the fact that thinner plates can be used. However, these steels tend to have weldability problems due to the hydrogen cracks (HC). The aim of this study was to investigate the relationship between heat input variation and the origin of HC, with gas and without purge gas, using implant test coupled to an acoustic emission system in order to define the moment of crack formation and its propagation. The welding process used was the FCAW-S and as the filler metal it was used a self-shielded tubular wire E71T-11. In this study, it was possible to verify the influence of the use of shielding gas and welding energy in the formation of the microstructure and development of crack in the material of study, demonstrating the efficiency of the AE technique in the verification of HC.
Keywords
HSLA steel, hydrogen cracks, acoustic emission, implant test, purge gas
