Investigation of QStE 420 TM steel materials weldability using different basic electrodes by electric arc welding method

Abstract

QStE 420 TM quality steel sheet plate materials, which are widely used in sectors such as defense industry and automotive industry, are made of fine-grained and micro-alloyed structure and are joined separately using the shielded metal arc welding method with the help of basic type rod electrodes with 3 different chemical compositions (E11018-G H4, E7018-1 H4R and E7018 H8 AWS coded). Mechanical and metallurgical effects on the welding zone (base material, heat-affected zone and weld metal) formed after the melting of electrodes with different chemical compositions in specified parameters; the samples were examined by applying macrostructure and microstructure examinations, as well as mechanical tests by applying tensile, bending, notch impact and hardness tests. As a result of the tests, the mechanical and metallurgical effects occurring in the weld zone were investigated by performing macro-micro structure examinations and applying tensile, bending, notch impact and hardness tests. In these tests, the fulfillment of the expected mechanical and metallurgical properties of the welded joints obtained from the basic electrodes of different compositions was examined in terms of weldability. Based on the comparative test results, the most appropriate results are; It was obtained from test samples that were combined in 4 passes with the electrode coded E7018 H8, at an average current intensity of 190 A, an arc voltage of 33 V and an average welding speed of 2.93 mm/second.