Analysis of the Effects of ZrO2 Nanoparticles on the Penetration in GMAW Process

Abstract

In this study, ZrO2 Nano-particles to improve the geometry and increased penetration welding has been used on the St37 sheet, in GMAW process. In the GMAW process of selecting appropriate values for the input parameters necessary in order to achieve weld is high with appropriate geometry and penetration. Since the stress-bearing capacity of the weld geometry, weld quality and also has an important role in determining the mechanical properties of the weld. In this study, the effects of voltage, wire feed speed, distance nozzle to the work piece, welding speed and coating thickness of ZrO2 Nano particles is intended as input parameters. The first, for coating Nano particles with specific dimensions on the surface of parts to be coated welding operation. After welding the weld penetration depth was evaluated. increasing the depth of penetration of the active coating on the surface (Nano zirconium oxide), which place the mechanisms leading to increased focus and arc current density at the top of the arc. Marangoni has also changed from negative to positive flow direction, the depth of penetration is increased. The results showed that fixed taking into account the input parameters and increase the coverage of ZrO2 Nano-particles on the surface to thickness 0.75 mm, weld penetration depth compared to non-Nano scale zirconium oxide coating has been increased. in addition to the effect of ZrO2 nanoparticles as a coating surface-active and increase the depth of penetration, such particles can cause tiny inclusions inside the structure weld, nucleation centers has been caused for the formation of acicular ferrite.