Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
Experimental analysis on the performance of SMA welding electrodes
Submission Author:
Felipe Batista , SC
Co-Authors:
Alisson Fernandes da Rosa, Felipe Batista, Victor Igor Berbare Lemos, Regis Henrique Goncalves e Silva
Presenter: Felipe Batista
doi://10.26678/ABCM.COBEM2021.COB2021-2010
Abstract
The Shielded Metal Arc Welding (SMAW), can be considered the most traditional and widespread among the arc welding processes, the electrodes can be differentiated, mostly because of the chemical composition of their coating. In this way, the electrodes can be cellulosic type, rutile type and basic type. However, some aspects and characteristics, present in bibliographies and commercial information about the electrodes, often, may not contemplate and highlight the particularities of different types of coating. The present study has the main objective of characterizing the performance of different electrodes classifications applying the manual welding process. To accomplish that, welding tests were carried out in the flat position (1G) and in horizontal position fillet weld (2F), with direct current in positive polarity (CC +) and alternating current (AC), in SAE 1020 steel plates with 9,6 mm thick. In the tests, five specifications of electrodes were evaluated, according to the AWS A5.1: E6010, E6011, E6013, E7018 and E7024, all with 3,25 mm diameter. The study is supported by acquisitions of the electrical current and voltage signals from the welding procedure, and macrographic analysis of the cross-section of the weld bead. The samples were prepared and chemically attacked with 2% Nital reagent, where it was possible to calculate the dilution between the base and filler metals of the weld beads. The results obtained allowed to evidence the static characteristic of the electric arc and to estimate the melting and deposition rate of the electrodes. In addition, the performance and potential of using alternating current with three tested electrodes was investigated. In this step, electrodes that are not commonly indicated for AC welding were also considered. These studies showed in general, the melting potential and penetration of cellulosic electrodes, the high deposition rate of basic electrodes, the stability of the arc of rutile electrodes, besides showing the high efficiency of deposition of electrodes with addition of iron powder in their compositions.
Keywords
SMAW, MMA, Arc Welding, Fusion Rate, Deposition Rate
