Superior protective performance of Ni Cr coating on stainless steel 316L in pure, oxygenated and chlorinated supercritical water

AbstractAdditive manufacturing (AM), and in particular selective laser melting (SLM) technology, allows to produce structural components made of lattice structures. These kinds of structures have received a lot of research attention over recent years due to their capacity to generate easy-to-manufacture and lightweight components with enhanced mechanical properties. Despite a large amount of work available in the literature, the prediction of the mechanical behavior of lattice structures is still an open issue for researchers. Numerical simulations can help to better understand the mechanical behavior of such a kind of structure without undergoing long and expensive experimental campaigns. In this work, we compare numerical and experimental results of a uniaxial tensile test for stainless steel 316L octet-truss lattice specimen. Numerical simulations are based on both the nominal as-designed geometry and the as-build geometry obtained through the analysis of µ-CT images. We find that the use of the as-build geometry is fundamental for an accurate prediction of the mechanical behavior of lattice structures.

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Crystallographic orientation dependence of Charpy impact behaviours in stainless steel 316L fabricated by laser powder bed fusion

Additive Manufacturing ◽

10.1016/j.addma.2021.102104 ◽

2021 ◽

pp. 102104

Author(s):

Xianglong Wang ◽

Oscar Sanchez-Mata ◽

Sıla Ece Atabay ◽

Jose Alberto Muñiz-Lerma ◽

Mohammad Attarian Shandiz ◽

...

Keyword(s):

Stainless Steel ◽

Crystallographic Orientation ◽

Charpy Impact ◽

Orientation Dependence ◽

Powder Bed Fusion ◽

Laser Powder Bed Fusion ◽

Stainless Steel 316L ◽

Powder Bed

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Oxidation Behavior of an Austenitic Steel (Fe, Cr and Ni), the 310 H, in a Deaerated Supercritical Water Static System

Metals ◽

10.3390/met11040571 ◽

2021 ◽

Vol 11 (4) ◽

pp. 571

Author(s):

Aurelia Elena Tudose ◽

Ioana Demetrescu ◽

Florentina Golgovici ◽

Manuela Fulger

Keyword(s):

Stainless Steel ◽

Supercritical Water ◽

Nuclear Reactor ◽

Electrochemical Impedance ◽

Electrochemical Methods ◽

Metallographic Analysis ◽

Gravimetric Analysis ◽

Static System ◽

Eis Measurements ◽

Supercritical Temperature

The aim of this work was to study the corrosion behavior of a Fe-Cr-Ni alloy (310 H stainless steel) in water at a supercritical temperature of 550 °C and a pressure of 250 atm for up to 2160 h. At supercritical temperature, water is a highly aggressive environment, and the corrosion of structural materials used in a supercritical water-cooled nuclear reactor (SCWR) is a critical problem. Selecting proper candidate materials is one key issue for the development of SCWRs. After exposure to deaerated supercritical water, the oxides formed on the 310 H SS surface were characterized using a gravimetric analysis, a metallographic analysis, and electrochemical methods. Gravimetric analysis showed that, due to oxidation, all the tested samples gained weight, and oxidation of 310H stainless steel at 550 °C follows parabolic rate, indicating that it is driven by a diffusion process. The data obtained by microscopic metallography concord with those obtained by gravimetric analysis and show that the oxides layer has a growing tendency in time. At the same time, the results obtained by electrochemical impedance spectroscopy (EIS) measurements indicate the best corrosion resistance of Cr, and (Fe, Mn) Cr2O4 oxides developed on the samples surface after 2160 h of oxidation. Based on the results obtained, a strong correlation between gravimetric analysis, metallographic analysis, and electrochemical methods was found.

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