Stainless steels are used in active environments, including food, due to their corrosion resistance, favorable mechanical properties, and good service life. Regarding austenitic stainless steel, AISI 316L is the most popular steel in the food industry, especially in the dairy industry. Welding is one of the most common processes used in joining materials to make and manufacture equipment in various industries. Due to the use of stainless steel in food and beverage industries to food processing and transportation equipment, using the connection and welding processes is necessary. In the various types of welding processes, gas tungsten arc welding (GTAW) is included. In food environments, the presence of protein is unavoidable, which can seriously affect the corrosion behavior and release of metal ions. This study aimed to identify the effect of Whey protein and welding on the corrosion behavior and ion release of the AISI 316L stainless steel bonding area welded by the GTAW method and three filler metals ER 316L, ER 309L, and ER 312 to find the filler metal suitable for welding. Steel and its utilization in the context of Whey protein. Initially, microstructural studies were performed using X-ray diffraction, light microscopy, and electron microscopy. The base metal microstructure was austenitic and the weld metal microstructure was a combination of ferrite and austenite phases. Then the hardness of different welding areas (base metal, heat affected area, and weld metal) was eva‎luated as hardness profiles due to the presence of ferrite at the boundary of austenitic grains in the area affected by heat and weld metal due to growth inhibition The grain increased hardness during unbalanced cooling. After microstructural studies, electrochemical tests including open circuit potential, dynamic potential polarization test and electrochemical impedance in stable conditions, and ion release test in turbulent conditions in PBS and PBS + 10 g / L Whey Protein solutions were performed for different samples. In general, in the presence of protein, the behavior of the samples was different from that of the similar state in the protein-free solution. In both solutions, the weld metal samples showed higher local corrosion sensitivity than the base metal, the most important reason being the separation of the element in the interface between the two phases of ferrite and austenite and the depletion of the austenitic phase of chromium and molybdenum during It is freezing. It should be noted that under turbulent conditions with a magnetic stirrer the presence of Whey protein ion release from samples prepared from base metal and weld metals was greatly increased. This study showed that the presence of Whey protein, abrasion, and welding conditions are factors that can greatly increase ion release and susceptibility to corrosion of materials in contact with food.

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عبدالمجيد اسلامي، عليرضا علافچيان