Analysis of corrosion on sintered stainless steel: Mechanical and physical aspects

This research aims to examine the effects of a corrosive atmosphere on samples of 316 L sintered stainless steel. A salt spray test chamber was used to simulate cyclic exposure to a corrosive environment. The samples were deposited using different process parameter sets by selective laser melting. The energy density (E-v) was varied on three levels, and the effects of volume energy density on the weight, density, and corrosion resistance were investigated. Furthermore, weight and density measurements were carried out at the end of the accelerated corrosion tests. The morphology of the corrosion sample surfaces was characterized by means of scanning electron microscopy. The mechanical properties before and at the end of the accelerated corrosion were evaluated according to yield strength, tensile strength, and elongation at breakage.The experimental results demonstrate that both the weight and density increase when E-v is increased. The corrosion tests exhibited slightly different corrosion behaviors as a function of the E-v used. Samples deposited at the maximum energy generally exhibited less corrosion and the highest tensile properties owing to the low distribution of defects inside the sample. However, improved tensile properties continued to emerge following each exposure time interval in the corrosion process. It was found that the influence of the "exposure time interval" factor is nonexistent for the ultimate tensile strength, yield stress, and strain at fracture, as these did not change with the accelerated corrosion exposure time.