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NanoMat 2018 Nano Research & Applications
ISSN: 2471-9838 Page 72
April 26-27, 2018
Rome, Italy
17th Edition of International Conference on
Emerging Trends in
Materials Science and
Nanotechnology
The most popular grades, thanks to their good mechanical
and corrosion properties, are austenitic and ferritic stainless
steel, which cover more than 95% of the global stainless steel
production. They are mainly used in the oil and gas, food,
chemical and construction industries. When a stainless steel
is exposed to relatively high temperatures for long period of
time, the precipitation of various intermetallic compounds and
phases can occur. This causes the sensitization of the steel, and
consequently brings about reduction of its corrosion resistance.
In a same way, intergranular carbides precipitation can generate
fracture susceptibility along boundaries. In general, hydrogen
can have a deleterious effect on metals, since only a small
amount is enough to cause serious degradation of corrosive and
mechanical properties. Second phases play very important role
in the hydrogen trapping behavior and have a significant effect
on the possible hydrogen embrittlement mechanism. In this work
several thermal treatments were carried out, considering different
cooling conditions on two stainless steel grades, AISI 316L and
AISI 446. Specifically, the objective of this work is to show the
effects of different kinds of precipitates (such as, carbides and
intermetallic phases) acting as hydrogen trapswhich can naturally
affect the corrosion behavior of steels. Hydrogen charging was
performed by the cathodic permeation method with graphite
anode and constant current density of 35 mA/cm2 for 3.5 h. A 1N
H2SO4 electrolyte solution was used, with the addition of 0.25 g/L
of NaAsO2 , before and after heat treatments. The microstructural
characterization carried out in both steels allowed to detect a
wide variety of carbides, with variable chromium contents and
different morphologies. The ferrite-carbide interfaces could be
identified as the main hydrogen trap sites in the AISI 446 and the
grain boundaries in the AISI 316L.
Recent Publications
1. Silverstein R, Glam B, Eliezer D, Moreno D and
Eliezer S (2018) Dynamic deformation of hydrogen
charged austenitic-ferritic steels: hydrogen trapping
mechanisms, and simulations. Journal of Alloys and
Compounds 731:1238-1246.
2. YuC, ShiueRK, ChenCandTsayLW(2017) Effect of Low-
Temperature Sensitization on Hydrogen Embrittlement
of 301 Stainless Steel. Metals 7:58.
3. Argandoña G, Palacio J F, Berlanga C , Biezma M V,
Rivero P J, Peña J and Rodríguez R (2017) Effect of the
temperature in the mechanical properties of austenite,
ferrite and sigma phases of duplex stainless steels
using hardness, microhardness and nanoindentation
techniques. Metals 7:219.
Biography
Prof. Dr. Graciela Mansilla, born 1963, received her MSc and PhD in Physics
at the National University of Rosario, Argentina. She is currently Associate
Professor and Researcher at the National Technology University of San
Nicolas (UTN-FRSN), Argentina. Her working area is associated with Phys-
ical Metallurgy of ferrous and non-ferrous alloys (stress relaxation, tensile
and fatigue behavior, wear and hydrogen embrittlement). She has numerous
publications in Congresses and Journals of scientific interest.
Prof. Eng. Mariano Inés, born 1985, received his Metallurgical Engineer
degree at the National Technology University of San Nicolas (UTN-FRSN),
Argentina. He is currently professor and researcher at the UTN-FRSN, Ar-
gentina. His work area is related with hydrogen embrittlement of steels and
its alloys. Currently he is working on his PhD in engineering at the Physical
Metallurgy Laboratory of the UTN-FRSN.
Hydrogen trapping sites in AISI 316L and AISI 446 stainless steels
Mariano N Inés and Graciela A Mansilla
UTN-FRSN, Argentina
Mariano N Inés et al., Nano Res Appl, Volume:4
DOI: 10.21767/2471-9838-C1-009