Evaluación experimental para caracterizar juntas de acero A36 soldadas mediante el proceso FCAW

Abstract

The present work had as objective the evaluation of mechanical properties and metallographic characterization of welded joints of ASTM A-36 steel through the FCAW process with cored wire E7lT11 of 1.2 mm in diameter; applying the AWS D1.1 2020 welding code. Changes were made in variables such as voltage, current intensity, and feed speed. The welding process was carried out with a Lincoln Arc R3S equipment. The joints were welded in 3 thickness groups, each group has 4 variations in the weld seam. In addition, the welding processes have a backup WPS. Once the weld beads were made, ultrasound tests and visual inspection were applied to rule out discontinuities, surface imperfections and incomplete fusion. Subsequently, the specimens for the different tests with their respective coding were obtained from each welding coupon. In the corresponding test tubes for rnicrographs, it was possible to identify the filler material, base material and the zone affected by heat, the same in which the microstructure was identified and then compared with the base material. With the use of a durometer, the hardness profile in the base material, ZAC and the filler material was deterrnined. It is concluded that after applying the non-destructive and destructive tests, better conditions were achieved with the parameters established in the WPS of the following coupons FCAW-230-6, FCAW-225-8, FCAW-300-8 and FCAW-225- 10, evidencing that its mechanical and metallographic properties do not change significantly. It is recommended that the specimens obtained from the weld coupons have a refrigerated cut so that there is no type ofheating that can vary mechanical and metallographic properties, therefore it will modify the results obtained.