Efeito dos parâmetros de soldagem sobre a microestrutura e as propriedades mecânicas de juntas de pino M6 com chapa hot stamping utilizando o processo stud welding.

Abstract

The appropriate selection of the materials to be used and a process parameters correctly preset are factors that precisely reflect on the quality of the welded Tuckers Stud, process known as Stud Arc Welding (SW). This process has been drawing the attention of automotive industry due to its versatility and application, also by joining Studs with sheets of Ultra – High Resistance such as Hot Stamping. In this work it were used different process combination between Tuckers Studs and Hot Stamping sheets (welding current, time and lift). Specimen were made from process combination with the purpose of evaluating the weld quality by means of the microscopy, hardness, tensile strength testing and torque. Through microscopy and Vickers microhardness test, was verified that there is microstructure variation on the welded parts in the behavior of the HAZ (Heat Affected Zone). Porosity appear on the fusion welding area acting as tension concentrator during mechanical stresses. The mean values of weld penetration and tensile strength are strongly influenced by the process parameters, where the welding current has greater interference in these results, followed by time and lift. In the case of torque values, the welding time was the process parameter that showed the greatest influence during the tests.