Search results for "316L"

Influences of atomization process and precursor material on the compaction mechanisms and metallurgical properties of parts developed by HIP

2022

Hot Isostatic pressing process is based on the densification of metals powders to near net shape parts with higher mechanicals properties than forged chemical equivalent. The precursor material can influence the parts properties. Thus the aims of this these is to understand the influence of the powder properties on the HIP parts. The particles characterization and the elements and compound monitoring during the HIP cycle allowed to understand the different oxidations phenomenons and their impact on the mechanical properties of parts. The comparison of differents powders batches with identical particles size repartition or identical chemical composition showed that the chemical composition a…

Galvanic deposition and characterization of brushite/hydroxyapatite coatings on 316L stainless steel

2016

In this work, brushite and brushite/hydroxyapatite (BS, CaHPO4·H2O; HA, Ca10(PO4)6(OH)2) coatings were deposited on 316L stainless steel (316LSS) from a solution containing Ca(NO3)2·4H2O and NH4H2PO4 by a displacement reaction based on a galvanic contact, where zinc acts as sacrificial anode. Driving force for the cementation reaction arises from the difference in the electrochemical standard potentials of two different metallic materials (316LSS and Zn) immersed in an electrolyte, so forming a galvanic contact leading to the deposition of BS/HA on nobler metal. We found that temperature and deposition time affect coating features (morphology, structure, and composition). Deposits were char…

Study of interface formation during diffusion bonding : compact heat exchangers application

2014

Compact diffusion bonded heat exchangers are an attractive option in many fields (nuclear, (petro-)chemistry, solar…) due to their performance. This type of concept is especially intended for manufacturing the energy conversion system of the ASTRID reactor. During diffusion bonding by HIP, the problem is twofold: the channel deformation and microstructure evolution must be controlled, while at the same time, highly resistant interfaces are desired. This thesis is focused on the understanding and the control of the bonded components microstructure prepared by HIP in order to define « process » criteria to achieve welds in agreement with specifications of components containing fluidic channel…

A comparison between the chemical behaviour of lead-gold and lead-bismuth eutectics towards 316L stainless steel

2013

Radiochimica acta, 101 (10)

One-step electrodeposition of superhydrophobic coating on 316L stainless steel

2021

Superhydrophobic coatings were fabricated through a one-step electrochemical process onto the surface of 316L stainless steel samples. The presence of hierarchical structures at micro/nanoscale and manganese stearate into the coatings gave superhydrophobicity to the coating, with contact angle of ~160°, and self-cleaning ability. Corrosion resistance of 316L samples was also assessed also after the electrodeposition process through Electrochemical Impedance Spectra recorded in an aqueous solution mimicking seawater condition.

Passivation-Induced Physicochemical Alterations of the Native Surface Oxide Film on 316L Austenitic Stainless Steel

2019

Time of Flight Secondary Ion Mass Spectroscopy, X-Ray Photoelectron Spectroscopy, in situ Photo-Current Spectroscopy and electrochemical analysis were combined to characterize the physicochemical alterations induced by electrochemical passivation of the surface oxide film providing corrosion resistance to 316L stainless steel. The as-prepared surface is covered by a ~2 nm thick, mixed (Cr(III)-Fe(III)) and bi-layered hydroxylated oxide. The inner layer is highly enriched in Cr(III) and the outer layer less so. Molybdenum is concentrated, mostly as Mo(VI), in the outer layer. Nickel is only present at trace level. These inner and outer layers have band gap values of 3.0 and 2.6-2.7 eV, respe…

Study of Passive Films Formed on AISI 316L Stainless Steel in Non-Polluted and Underwater-Volcano-Polluted Seawater

2014

This work studies the semiconducting behavior of passive films formed on AISI 316L (UNS S31603) in two different sea-water solutions, non-polluted and polluted, collected from the volcano of El Hierro Island. Polarization measurements, potentiostatic passivation tests, electrochemical impedance spectroscopy, and capacitance measurements were performed. Results show that the polluted seawater worsens passivation kinetics. Additionally, passive films formed on AISI 316L stainless steel in polluted seawater have been found to be less protective than those formed in non-polluted seawater, showing a more defective structure, owing to the acidity of the polluted medium.

Physico-chemical characterization of passive films on 316L stainless steel grown in high temperature water

2014

Brushite/Hydroxyapatite Coatings obtained by galvanic deposition on 316L Stainless Steel

2016

Hydroxyapatite (HA, Ca10(PO4)6(OH)2) is a basic calcium phosphate mineral with chemical composition similar to that of bones and teeth. Owing to this peculiarity HA is a biocompatible material of high medical interest. Unfortunately, it possesses poor mechanical properties, because is brittle, has a low fracture resistance and a poor wear resistance. For these reasons, in the last years the research was been focused on the use of HA as a coating of another biomaterial that acts as support. The best choice is that to use a substrate that must be bionert and mechanically stable, such as 316L stainless steel (316LSS). This is useful for biomedical implants, because of its excellent biocompatib…

Photoelectrochemical monitoring of rouging and de-rouging process on AISI 316L for chemical reactors

2016

The food and fine-chemical industry has for a long time been troubled by red brown to dark violet deposits in distillation columns, storage vessels and distribution systems for purified water and clean steam. Owing to the visual appearance of those deposits, the phenomena was referred as rouge. Although formation of rouge, i.e. rouging, is a commonly known phenomenon in stainless steel systems, the basic mechanism is still not fully understood. The phenomenon causes precipitation of iron as fine red-brown ferric oxide or hydroxide particles. Moreover adherent discoloration of the stainless steel surface is often observed in conjunction with the loosely adhered rouge particles. The affected …