Search results for "Surface treatment"
showing 10 items of 29 documents
The Influence of Surface Treatment on the Kinetic of Growth of Anodic Films on Magnesium in Alkaline Solution
2010
Laser surface treatments for adhesion improvements of aluminium alloys structural joints
2007
Abstract Laser technology is proposed as a friendly alternative treatment to chemicals involved in conventional prebonding adherend treatments. Aluminium alloy 2024 substrates were laser treated with different beam diameters and energy densities, and bonded using a structural epoxy adhesive. The influence of irradiation conditions on adherends morphology and adhesive joints’ fracture energy was investigated. On the basis of different morphologies observed, an explanation of the effect of the surface treatment upon joint mechanical behaviour is attempted.
The influence of surface treatment on the anodizing of Magnesium in Alkaline Solution
2008
Influence of anodizing surface treatment on the aging behavior in salt-fog environment of aluminum alloy 5083 to fiber reinforced composites adhesive…
2021
The present work aims to evaluate how an innovative and eco-friendly anodizing process with tartaric-sulfuric acid (TSA) bath and a pore widening in an aqueous solution of NaOH 0.1 M can improve the durability in marine environment of co-cured adhesive joints between an aluminum alloy (AA 5083) and fiber (i.e., glass or basalt)-reinforced composite substrates. The aging was carried out by exposing samples to salt-fog spray conditions (5 wt.% NaCl) for 30, 60 and 90 days in a climate chamber, in accordance with ASTM B117. In order to get further insights on the aging behaviour of bonded joints, neat matrix was also exposed to the same environment for 60 days. Quasi-static mechanical tests an…
Adhesive joining of Aluminum AA6082: the effect of resin and surface treatment
2009
Abstract In this work the effects of both the substrate surface condition and the adhesive properties on single-lap aluminium joint resistance were analysed. The aluminium sheets were mechanically treated with two abrasive surfaces evaluating the induced roughness; four different resins were used in adhesion tests. Moreover, wettability tests were performed in order to evaluate the effect of the above-mentioned parameters on the substrate/adhesive interaction. A design of experiments was defined in order to quantify the effect of the considered factors and their correlation.
TRITIUM - A Real-Time Tritium Monitor System for Water Quality Surveillance
2018
In this work the development results of the TRITIUM project is presented. The main objective of the project is the construction of a near real-time monitor for low activity tritium in water, aimed at in-situ surveillance and radiological protection of river water in the vicinity of nuclear power plants. The European Council Directive 2013/51/Euratom requires that the maximum level of tritium in water for human consumption to be lower than 100 Bq/L. Tritium levels in the cooling water of nuclear power plants in normal operation are much higher than the levels caused by the natural and cosmogenic components, and may easily surmount the limit required by the Directive. The current liquid-scint…
Surface investigation of plasma HMDSO membranes post-treated by CF4/Ar plasma
2002
Fluorination treatment has been performed on polysiloxane membranes using a plasma glow discharge of a gases mixture CF4 and argon (plasma enhanced chemical vapor deposition). Atomic force microscopy, XPS analyses and contact angle measurements have been undertaken to explain the surface transformation and behavior, which strongly depend on the morphology, the composition and the hydrophilic/hydrophobic character of the plasma-polymerized initial membranes. Main result is that fluorination, which leads to hydrophobic membranes, has a more relevant effect on amorphous silica-like membranes than on polymer-like ones, according to their chemical composition whereas the plasma surface reaction …
Dynamic Mechanical Behavior Analysis of Flax/Jute Fiber-Reinforced Composites under Salt-Fog Spray Environment
2020
Over the last decades, natural fiber-reinforced polymer composites (NFRPs) gained great attention in several engineering fields thanks to the reduction of the environmental impact and the end-of-life cost disposal. Unfortunately, the use of NFRPs is limited, mainly due to their weak resistance against humid environments. Since limited literature is available about the evolution of the dynamic mechanical response of NFRPs under aggressive environments, this paper aims to investigate the damping properties of flax, jute and flax/jute epoxy composites exposed to salt-fog up to 60 days. Furthermore, sodium bicarbonate fiber treatment was performed to improve the composites&rsquo
Torque de desinserción y propiedades fisico-químicas de implantes dentales grabados con ácidos fluorhídrico y nítrico: Estudio experimental en perros
2006
Objetivo: Estudiar la composición, características superficiales y respuesta al torque de desinserción de una superficie implantaria tratada inicialmente con ácido fluorhídrico y posterior pasivado con ácidos fluorhídrico y nítrico. Diseño del estudio: En una primera fase, se seleccionaron 12 implantes en los que se estudiaron las características fisico-químicas mediante mediciones de energía dispersa de rayos X (EDS), microscopio electrónico de barrido y análisis de XPS (espectrometría de fotoelectrones). Asimismo, se colocaron 24 implantes -doce de 8 mm y doce de 10 mm de longitud-, en seis perros beagle, en los que tras un período de reposo, se procedió a la retirada de 12 implantes a la…
The role of oxidation treatments before and after CVD synthesis of graphene on copper catalytic surface
2021
Graphene is a sheet of honeycomb bonded carbon, that is only one atom thick. Aside from its remarkable strength, graphene has great conducting and photochemical prop erties. Due to its unique properties, it can be used as viable option for rare metals in circuits and in new type of measuring components. To express these properties at their best, graphene should be single crystal and as clean as possible. In this bachelor thesis, different treatment options for catalytic metal surface for graphene synthesis are studied in chemical vapor deposition growth. Different options to treat the catalytic metal layer were studied, such as changes in gas compositions in annealing process, electropolish…