In the present work, interaction of a mixture biocide, sodium hypochlorite (NaClO), and biopolymer, xanthan, with carbon steel coupons exposed to seawater in turbulent flow regime was studied. The cell concentrations, corrosion rates, biomasses, exopolysaccharides (EPSs) produced on coupon surfaces various treatments were quantified. products evaluated using X-ray diffraction (XRD), steels analysed by scanning electron microscopy (SEM). results indicated that xanthan hypochlorite-xanthan...

This report is a summary of the initial research done with Al 4wt% Mg nanocrystalline alloy, obtained by mechanical alloying in liquid N 2 , reinforced diamond nano sized particles (4-5 nm). At this stage, cryomilling conditions have been optimized to obtain alloy powder and effectively incorporate reinforcement particles. Additionally, adopted process ensures efficiency particle distribution.

This article studies changes observed on the R-phase thermoelastic behavior in a near-equiatomic Ti-Ni shape memory alloy. Three kinds of procedures have been performed: different treatments, thermomechanical cycling under constant loading helical springs and thermal as-treated trained samples. Several heat treatments were carried out to investigate evolution by differential scanning calorimetry (DSC). A treatment was chosen which is absent. Shape produced submitted training process an...

This paper aimed to develop and characterize superhydrophobic surfaces with anticorrosive properties obtained by the chemical modification of 5052 aluminum alloy variation acid etching time, formation lamellar double hydroxides (LDH) film immersion in stearic acid. The specimens were etched HCl (2M) at 5, 10 30 min. plates treated aqueous solution zinc nitrate (0.1 M) presence ammonia then immersed a ethanol (1% w/w) reduce surface energy. Contact angles (CA) determined. Surface morphology...

The most notable characteristic of Orbital TIG welding is the constant geometric profile tubes. In context orbital tubes with a large diameter and thick walls, relationship between position, use or pulsed current also value average on characteristics beads obtained was studied. We deposited welds SAE 1020 carbon steel tubes, as well taking macrographs cross-sections using optical microscopy. High-definition films were used to understand behaviour weld pool in different positions. quantified...

Biocorrosion is the main process that causes pipeline damages and losses in oil industry. The objective of this work was to investigate influence biofilm forming microorganisms on biocorrosion X80 steel exposed produced water through microbiological characterization, film analysis by optical microscopy scanning electron microscopy, weight loss surface laser confocal microscopy. Changes after 360 days were attributed planktonic cells, temperature conditions, contact with air, photo-oxidation,...

The present study aimed to develop and characterize super-hydrophobic nickel coatings through the electrodeposition process, employing myristic acid as a surface energy reducing agent, with objective of enhancing corrosion resistance. ASTM A36 carbon steel (E00) specimens served substrates for application three different coating conditions: pure (E10); associated (E01); bilayer structure consisting base layer succeeded by an additional enriched (E11). samples were characterized Optical...

Environmental and economic concerns accelerated biofuels research industrial production. Many countries have been using diesel biodiesel blends as fuels justifying on biofilms formation metals corrosion. Cylinders made of AISI-1020 carbon steel with an exposed area 1587 mm 2 , water, water associated B3 fuel (diesel/biodiesel blend at 97 : 3 v/v) were used.The was detected, biocorrosion detected AISI-1020. The results showed a variation in sessile microflora during the experiments. In...

This paper present a thermomechanical study of actuators in form helical springs made from shape memory alloy wires that can work as actuator and/or sensor. These abilities are due to the martensitic transformation. transformation is diffusionless phase transition occurs by cooperative atomic rearrange mechanism. In this work, spring were manufactured Cu-Zn-Al wires. The submitted constant tensile loads and thermal cycles. procedure allows determine thermoelastic properties springs....

Aluminum alloy metal matrix composites are a class of materials object large and intensive research during the last years. In this study an AA2124 aluminum were processed by means mechanical alloying added 10, 20 percent silicon carbide (SiC) in vibratory SPEX type mill 60 120 minutes. After powders obtained characterized Scanning Electron Microscopy (SEM) plus Energy Dispersive Spectroscopy (EDS) to determine morphology. order consolidate reinforced composites, high energy ball milling...

Co-Ni/SiC nanocomposite coatings were obtained by codeposition of SiC nanoparticles in a bath with nickel and cobalt, using API 5L X80 as the substrate. The influence cathodic current density on deposit properties was investigated. Measurements electrochemical impedance spectroscopy (EIS) potentiodynamic polarization (PP) performed 3.5 wt% NaCl solution to investigate corrosion performance. morphology chemical analysis surfaces analyzed scanning electron microscopy (SEM) coupled energy...

The use of nanocomposite coatings on carbon steel has been very promising. In this paper, the formation mechanism multilayer Ni-Co/SiC coating electrodeposited in API 5L X80 was investigated. were obtained by galvanostatic deposition technique using a single bath and cathodic current density value. results showed variation morphology chemical composition both surface along cross-section at all time conditions tested, confirming functional gradient coating. occurred through mechanism, with...

Refill friction stir spot welding (refill FSSW) is a solid state joining technology developed and patented by Helmholtz-Zentrum Geesthacht. FSSW process suitable for lightweight materials in similar dissimilar joint configuration. The result welded lap configuration with minimal material loss flat surface no keyhole. In the present study, refill was applied to join 6061 aluminum alloy sheet 1.25 mm thickness. objective of this work investigate influence hook on microstructure mechanical...

High performance nanostructured light metals and alloys are very interesting for replacing conventional heavier materials in many industrial components. Energy Ball Milling Cryomilling useful techniques to obtain nanocrystalline powders. In this work the effect of several milling conditions such as rotation speed, time, ball powder ratio temperature on crystallite particle size morphology pure aluminum presented. X-Ray Diffraction, Laser Diffraction Scanning Electron Microscopy used. energy...