A5029716010- Metal and Thin Film Mechanics
- Metal Alloys Wear and Properties
- Plasma Diagnostics and Applications
- Plasma Applications and Diagnostics
- Advanced materials and composites
- Hydrogen embrittlement and corrosion behaviors in metals
- High-Temperature Coating Behaviors
- Diamond and Carbon-based Materials Research
- Microstructure and Mechanical Properties of Steels
- Dust and Plasma Wave Phenomena
- Erosion and Abrasive Machining
- Advanced ceramic materials synthesis
- Semiconductor materials and devices
- High Temperature Alloys and Creep
- Corrosion Behavior and Inhibition
- Surface Modification and Superhydrophobicity
- High Entropy Alloys Studies
- Intermetallics and Advanced Alloy Properties
- Aluminum Alloys Composites Properties
- Metallurgical Processes and Thermodynamics
- Metallurgical and Alloy Processes
- Welding Techniques and Residual Stresses
- Bone Tissue Engineering Materials
- Icing and De-icing Technologies
- Additive Manufacturing and 3D Printing Technologies
Universidade Federal do Paraná
2015-2024
Universidade Federal de Santa Catarina
2002-2024
Centre National de la Recherche Scientifique
2006-2023
Institut des Nanotechnologies de Lyon
2023
École Centrale de Lyon
2023
Institut National des Sciences Appliquées de Lyon
2023
École d'Ingénieurs en Chimie et Sciences du Numérique
2023
Université Claude Bernard Lyon 1
2023
Instituto Federal de Educação, Ciência e Tecnologia de Minas Gerais
2021
Universidade Federal de Sergipe
2016
DC plasma is a very promising technology for processing different materials, and becoming especially interesting when low environmental impact high-performance treatments are needed. Some of the intrinsic characteristics technology, which make it suitable powder metallurgy (PM) injection molding (PIM) parts production, low-pressure environment high reactivity. Moreover can be considered as highly competitive green technology. In this work, an overview some important techniques applied to PM...
The present paper reports the experimental results on martensitic stainless steel low-temperature plasma assisted carburizing kinetics. treatments were carried out using a gas mixture of 99.5% (80% H2 + 20% Ar) 0.5% CH4 at temperatures 623, 673, 723 and 773 K for times 4, 8, 12 16 h. peak voltage pulse period pulsed DC power supply kept constant 700 V 240 μs, respectively. Temperature was controlled by adjusting duty cycle. treated samples characterized confocal laser scanning microscopy,...
Low-temperature plasma carburizing was studied aiming to determine the effect of gas mixture and flow rate on surface properties AISI 420 martensitic stainless steel samples. Plasma carried out for mixtures 20% Ar + 80% H2 comprising CH4 contents between 0.25 1.00%, rates ranging from 1.67 × 10− 6 6.68 Nm3 s− 1. The modified layers were characterized by confocal laser scanning microscopy, X-ray diffractometry microhardness measurements. also optical emission spectrometry. Results indicate...
Low-temperature plasma assisted nitriding is a very promising technique to improve surface mechanical properties of stainless steels, keeping unaltered or even improving their corrosion resistance. During treatment, nitrogen diffuses into the steel surface, increasing its hardness and wear In present work process different martensitic steels was studied. As-quenched AISI 410, 410NiMo, 416 420 samples were nitrided at 300, 350, 400, 450, 500°C, for 4 h, 3 Torr, in gas mixture 70% N2 + 20% H2...
The influence of the content and nature impurities on rotational temperature three probe molecules (OH, NH ) in a helium plasma created microwave resonant cavity is investigated by synthetic spectra method mass spectrometry. OH found to be only reliable obtain satisfactory estimation gas temperature. In our experimental conditions, depending impurity, varies strongly at 500 ppm, for instance, difference 700 K possible (∼30% mean temperature).
Abstract Demand for higher wear and corrosion resistance components has attracted increasing interest in surface engineering. This line of research develops alternative processes improving the properties engineering materials. The traditional route seeks development new alloys. However, cost time associated with these developments become prohibitive many cases. Currently, application plasma-assisted thermochemical treatments been a technically economically viable to extend lifespan exposed...
The influence of weak concentrations oxygen on the density He(2 3S) metastable states was measured by laser atomic absorption spectroscopy in a microwave He–O2 plasma sustained resonant cavity. number decreases factor five when 500 ppm O2 are introduced helium. Since pure helium, sustain afterglow for hundreds microseconds, behaviour time is next investigated. Photon counting used to observe evolution four optical transitions from He(n = 3) 2) levels afterglow. last step intensity followed...
When plasma optical spectroscopy is applied to on-line welding quality monitoring, the electronic temperature commonly selected as spectroscopic parameter determine. However, several processing stages have be considered in this case, including emission line identification, which significantly costly terms of computational performance. In paper, wavelength associated with maximum intensity background proposed new monitoring signal, it will demonstrated that there a clear correlation between...
A small-scale microwave postdischarge at atmospheric pressure is studied. Its shape evolves from a straight beam of light to diverging cone. By using the method synthetic spectrum, mean temperature shown vary nonlinearly between 1000 and 2000K. Evaluation Reynolds number shows linear dependence on flow rate suggests transition laminar turbulent flow. Simultaneously, gas velocity increases comes exceed sound velocity. As increases, three regimes are distinguished: subsonic, transonic, supersonic.
A collisional–radiative model is proposed to describe the behaviour of a helium plasma sustained in resonant cavity at atmospheric pressure. set rate constants 2450 K. Indeed, most available data literature are reliable below 500 It shown that time post-discharge mainly controlled by ambipolar diffusion during first ten µs, next electron-assisted recombination ions and finally chemionization from excited state. This lasts for hundreds µs. due slow electrons together with chemionization....