This study presents an investigation of the plunge stage in joining AZ31B magnesium alloy with friction stir welding using two different 3D finite element models based on Arbitrary Lagrangian–Eulerian formulation and Coupled Eulerian–Lagrangian formulation. The investigations are made with the ABAQUS program. Johnson–Cook plastic material law and Coulomb friction law are used in both models. Models are compared in terms of temperature, strain distribution, and processing time. In both models, very similar temperature and strain distributions are obtained in the weld zone and the models are validated by experimental results. In addition, with the increase in the rotational speed of the tool, temperature and strain in the welding zone increase similarly in both models. In the model using the Arbitrary Lagrangian–Eulerian formulation, mesh distortions occur when high mesh density is not created in the plunge zone. No problems related to mesh distortion are encountered in the model using Coupled Eulerian–Lagrangian formulation. Moreover, it is found that the model using the Coupled Eulerian–Lagrangian formulation has a lower processing time and this processing time is not affected by the rotational speed of the tool.

Purpose: Determination of the tensile behavior of welded constructions made of austenitic stainless steel in corrosive environments is of great importance for the safer use of the construction. When austenitic stainless steels are welded together, welding defects can occur in some cases. And stainless steels are used in corrosive environments. Thus, we are aimed to investigate the effect of welding defects the tensile behavior in corrosive environment of AISI 304 L stainless steel joined with shielded metal electrode. Design/methodology/approach: Hardness measurements and micro-macro structures examination were made before the corrosion test to characterize the structure of the weld zone. Corrosion tests were carried out in accordance with EN ISO 9227 by exposing the welded tensile specimens to salt spray for 24-96-240-480-720-1000 hours. After the salt spray test, tensile tests were performed. The fractured surfaces were examined following the tensile tests by scanning electron microscope (SEM). Findings: A significant decrease in the tensile strength of the material was observed with the increase of the salt spraying period as a result of the tests. It is worth noting that corrosion products were occurred especially in the areas of welding defects. Research limitations/implications: This study was performed on materials containing welding defects. In addition, the corrosive environment was provided by salt spraying. It should not be forgotten that the materials may behave differently in different corrosive environments. Originality/value: While there are studies regarding effects of welding defects and corrosion individually, no study has been found in the literature which considers the effect of welding defects within corrosive environments on the material strength. Therefore, this study presents novel findings by considering both detrimental effects at the same time. The study shows significant decrease in strength of the material due to welding defects and corrosive environment.

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