Applications of Wrought Austenitic Stainless Steel Corrosion Testing to Laser Powder Bed Fusion 316L

Recent developments in the 3-D printing of austenitic stainless steels have led to the need for standardization of electrochemical techniques used to assess the corrosion performance of these alloys. Currently, ASTM standards for austenitic stainless focus on assessing their resistance to different modes of corrosion such as pitting, crevice, and intergranular corrosion. Due to the complexity of the additive process, selective corrosion occurs in microstructural features such as cellular structures and melt pool boundaries. Standardized corrosion testing needs to incorporate these microstructural features. This study characterizes the corrosion behavior of LPBF stainless steel in a variety of ASTM standards with special attention to melt pool boundary dissolution, cellular structures, and intergranular corrosion.

The Effectivity of Oil Palm Inhibitor Processed by Aminolysis to Control Corrosion on Steel in Sodium Chloride Environment

A green inhibitor based on Palm kernel oil (PKO) was prepared to investigate its corrosion inhibition behaviour against steel ASTM A36 in sodium chloride solution. The aminolysis method was used to synthesize the green inhibitor and produced fatty acid diethanolamine. Afterwards, the mixture of PKO and diethanolamine of 1:6 and 1:20 were prepared. These mixtures were added into sodium chloride solution with concentration 50, 100, 500, and 1,000 ppm and they were used as working solution in corrosion testing. Corrosion testing was conducted using anodic polarization. The confirmation of microstructure of steels surfaces were done by optical microscope. The results obtained from corrosion testing showed that inhibitors of palm oil, especially palm kernel oil (PKO), provided a good corrosion protection effect. The present work provided very promising results in the preparation of green corrosion inhibitors.