ISOLDA COSTA

Resumo

Graduated in Chemical Engineering from the State University of Campinas (1981), obtained a Master's degree in Nuclear Technology - Materials from the University of São Paulo (in 1986) - IPEN and a pH.D. from the University of Manchester Institute of Science and Technology (UMIST) - Corrosion and Protection Center ( 1991). In 1984 joined the Energy and Nuclear Research Institute working at the Materials Science and Technology Center. In 1987, went for her doctorate at the University of Manchester Institute of Science and Technology, having resumed her duties at IPEN in early 1992. Since 1992 ahas been working s a postgraduate advisor in the Nuclear Technology program at IPEN-USP. Works in research in the area of ​​Corrosion and Protection against corrosion, Surface Treatments for corrosion resistance, studies of correlation between microstructure and corrosion of IPEN. In May 2019, assumed the Directorate of Research, Development and Teaching at IPEN, a position that is currently held at the institution. The main topics of interest for research are corrosion in aluminum alloys, stainless steel, biomaterials and surface treatments using clean technology processes. (Text obtained from the Currículo Lattes on October 14th 2021)


Possui graduação em Engenharia Química pela Universidade Estadual de Campinas (1981), mestrado em Tecnologia Nuclear - ênfase em Materiais pela Universidade de São Paulo (1986) - IPEN e doutorado pela University of Manchester Institute of Science and Technology (UMIST) - Corrosion and Protection Centre (1991). Ingressou no Instituto de Pesquisas Energéticas e Nucleares em 1984 no Centro de Ciência e Tecnologia de Materiais. Em 1987 se afastou do IPEN para realização do doutorado na University of Manchester Institute of Science and Technology, havendo retomada suas funções no IPEN no início de 1992. Atua desde 1992 como orientadora de pós-graduação no programa de Tecnologia Nuclear do IPEN-USP. Atua em pesquisas na área de Corrosão e Proteção contra a corrosão, Tratamentos de Superfície para resistência à corrosão, estudos de correlação entre microestrutura e corrosão do IPEN. Em maio de 2019 assumiu a Diretoria de Pesquisa, Desenvolvimento e Ensino do IPEN, função que exerce atualmente na instituição. Os principais temas de interesse de pesquisa são em corrosão em ligas de alumínio, em aços inoxidáveis, em biomateriais e tratamentos da superfície por processos de tecnologia limpa. (Texto extraído do Currículo Lattes em 14 out. 2021)

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Agora exibindo 1 - 10 de 543
  • Resumo IPEN-doc 30341
    Corrosion and anodizing behavior of dissimilar AA5052-H32 and AA6061-T6 alloys joined by metal inert gas welding
    2023 - KLUMPP, RAFAEL E.; AKBARZADEH, SAJJAD; DELAUNOIS, FABIENNE; COSTA, ISOLDA; OLIVER, MARIE-GEORGES
    Enormous efforts have been made to reduce fossil fuel consumption and greenhouse gas emissions in several sectors, such as the transport and agricultural sectors. Weight reduction is an efficient way to reduce fuel consumption. In this context, Aluminum alloys are excellent choices due to their properties of lightweight and high strength. However, corrosion is a major concern when using dissimilar alloys joined by welding. This might result in galvanic corrosion. Also, thermal effects during welding might affect the microstructure and the material corrosion resistance. Consequently, the study of dissimilar materials joined by welding is of great importance. In order to decrease corrosion susceptibility, surface protection of aluminum alloys against corrosion is a core issue in these applications. In this work, the corrosion resistance of the AA5052- H32 and AA6061-T6 alloys welded by metal inert gas (MIG) welding, with or without TSA anodizing, was investigated. The corrosion resistance was evaluated by immersion tests in sodium chloride solution and monitored by electrochemical impedance spectroscopy (EIS) and as scanning vibrating electrode technique (SVET). The anodic layers formed by TSA anodizing were analyzed and characterized by Scanning Electron Microscopy with EnergyDispersive Spectroscopy (SEM-EDS) and Transmission Electron Microscopy (TEM). The results present the correlation between corrosion resistance, microstructure and surface film characteristics.
  • Resumo IPEN-doc 30340
    Characterization of the microstructure and corrosion behavior of electrodeposited FeMn films for bioabsorbable implants applications
    2023 - GABBARDO, ALINE D.; FERREIRA, JANE Z.; COSTA, ISOLDA
    Corrosion of biodegradable implants is not supposed to be avoided, but controlled to reach a target biodegradation rate [1-4]. Implants made of Fe or its alloys have been studied for this type of applications; however, they have some drawbacks as low corrosion rates for this application, accumulation of bulky corrosion products and ferromagnetic properties, which might be a problem for MRI exams [1-4]. Some improvements have been proposed in the literature, such as using electrodeposition to produce thin strut walls of Fe (or alloys) with high purity and using FeMn alloys (with high concentrations of Mn) that can form an antiferromagnetic phase with higher corrosion rates than pure Fe [1-6]. In the first part of this work, thin films of FeMn alloys were electrodeposited from sulfate electrolytes. The effects of additives and electrodeposition current density were evaluated through electrochemical techniques. The microstructure of the electrodeposited films was characterized by SEM/EDX and XRD. The surface finishing and magnetic properties were evaluated by AFM/MFM techniques. The results showed that FeMn films with a maximum concentration of 18 wt% of Mn were obtained at an applied cathodic current density of 80 mA/cm2 (close to the limiting current density) for a 1:5 ratio of Fe2+ and Mn2+ in the electrodeposition bath. These films were mainly composed of alfa-FeMn phase that still showed magnetic response on MFM analysis. The use of additives such as buffer, surfactant, and leveling resulted in a more homogenous film with improved surface finishing. In the second part of this work, the biodegradation rate of the electrodeposited film will be evaluated through immersion and electrochemical techniques in simulated body fluids.
  • Resumo IPEN-doc 30339
    Characterization of the corrosion behavior of Zn-Al-Mg coated steel under São Paulo acidic rain by Scanning Vibrate Electrode Technique
    2023 - BOLSANELLO, MARILIA F.; ABREU, ANDREA; GUEDES, MARIA G.P.; COSTA, ISOLDA; PEREZ, JAVIER I.; ROSSI, JESUALDO L.
    Smart coatings tailored to enhance the corrosion protection of steel substrates are the target of the automotive industry, as they ensure the reliability and long-term performance of coated parts. In this field, galvanized steel progresses through the last decades entail the development of more durable, reliable, and sustainable anticorrosive coatings, reducing the need for additional corrosion protection on coated components, while also lowering costs and fuel consumption in automobiles. The addition of aluminum and magnesium to the zinc bath leads to the formation of different metallurgical products in the galvanized layer, as well as more compact and stable corrosion products, increasing the service life of the steel. Also, the addition of those elements contributes to a self-repairing effect on scratches and at the cut edges, a crucial region under corrosive agents. In this study, electrochemical techniques were used to understand the corrosive process that occurs in Zn-3.5%Al3%Mg alloy coated steel (ZM), when exposed to aggressive aqueous electrolytes, and the differences in its corrosion behavior with respect to conventional galvanized steels (GI). Besides the conventional polarization analysis, samples of ZM and GI were investigated by Scanning Vibrate Electrode Technique (SVET), a local probe technique outstanding in providing information about the corrosive process in situ, on the micrometer scale. Through SVET, it is possible to visualize the corrosion progress in terms of identifying anodic and cathodic regions with estimation of the respective currents and their evolution in space and time. The tests were performed synthetic acid rain, reproducing the conditions found in the city of São Paulo. The study was complemented by Scanning Electron Microscope (SEM), Energy Dispersive X-Ray Analysis (EDX) and Glow-discharge optical emission spectroscopy (GDOES) analysis, for the identification corrosion products formed after exposure to the corrosive electrolyte. The superiority of ZM corrosion resistance over GI has been proven and attributed to the different corrosion products formed by the alloying elements added to the coating, therefore not observed in the conventional galvanized steel.
  • Resumo IPEN-doc 30338
    Assessment of pitting corrosion in anodized 2xxx aluminum alloys
    2023 - ARAUJO, JOAO V. de S.; CHEN, JINGHUI; ZHOU, XIAORONG; COSTA, ISOLDA
    This work focus on the characterization of pitting corrosion initiated in 2xxx Al alloys anodized in Tartaric Sulphuric Acid (TSA), specifically the 2024-T3 alloy substrates, and the 2198, in the T8 and T851 tempers. The results were compared to that of anodized pure Al (99.99 wt.%). The pitting corrosion resistance of the anodized samples was tested by potentiodynamic polarization in 0.1 mol L-1 NaCl solution. The tested surfaces were then characterized by optical microscopy, optical profilometry, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and image analysis by ImageJ. The polarized samples presented pits of different sizes. Some pits presented diameters of several hundred microns, with the anodic films remaining as pit covers. The pits in all anodized samples showed similar characteristics, such as, a continuous pit cover with a central hole or a pit cover detached from the substrate in some small areas. The central hole serves as a diffusion channel for dissolved species within the pits. Detachment of the pit cover occurs due to accumulation of corrosion products within the pits leading to swelling of the anodic film and its detachment from the substrate. The results showed that pit size and depth analysis measured by optical profilometry can be misleading. Depth assessment should be carried out after removal of the anodic layer followed by crosssection of the anodized sample. The pits developed under highly occluded conditions. It was also observed that in the anodized alloys, as opposed to pure Al, pits are related to the defects in the anodic films due to dissolution of micrometric intermetallic particles during the anodizing process. Pitting attack propagation occurred according to the microstructure characteristics of the tested material.
  • Artigo IPEN-doc 30179
    Study of the effect of nanosecond laser texturing on the corrosion behavior of Ti6Al4V and Ti6Al4V parts produced by powder bed fusion
    2023 - QUEIROZ, FERNANDA M.; RIBEIRO, GLEICY de L.X.; CASTRO, RENATO S. de; SANTOS, ROGERIO G. dos; VIEIRA, ALEXANDRE; TERADA, MAYSA; BUGARIN, ALINE de F.S.; ROSSI, WAGNER de; COSTA, ISOLDA
    Combining metallic additive manufacturing with laser texturing could be an alternative in obtaining parts with functional hydrophilic surfaces, which improves osteointegration. Careful study of the corrosion behavior of the surfaces obtained is necessary, because the evolution of this phenomenon can influence the osteointegration of the implant, causing the release of metal ions in the body and even the rejection of the component. This study compared the corrosion behavior of laser texturing Ti6Al4V components with components manufactured using laser power bed fusion of the same alloy followed by laser texturing. Their microstructure, roughness, wettability, and electrochemical behavior were analyzed, and different morphologies and microtopographies were observed comparing both samples. The electrochemical tests obtained indicate that Ti6Al4V showed higher corrosion resistance than L-PBF Ti6Al4V after laser texturing. The results suggest that laser texturing can encourage cell proliferation and osseointegration on the surface of Ti6Al4V biomedical implants.
  • Resumo IPEN-doc 30167
    Influence of texturing parameters on surface modification of UNS S32101 duplex steel
    2023 - BUGARIN, ALINE de F.S.; RIBEIRO, GLEICY de L.X.; CASTRO, RENATO S. de; QUEIROZ, FERNANDA M.; SANTOS, ROGERIO G. dos; TERADA, MAYSA; COSTA, ISOLDA
    The application of laser texturing aims to modify the surface without changing its chemical composition. These alterations can be evaluated through mechanical, physical or chemical tests. Texturing can be applied to improve efficiency in industrial processes, such as the flowability of materials, by applying laser texturing to the internal surfaces of components. This work aims to evaluate the influence of texturing parameters in the flow process of industrial batchers. UNS S32101 lean duplex stainless steel (LDSS) samples were used for the tests. For laser texturing of the surfaces, laser of Yb was used, with a wavelength of 1064 nm (infrared), using the scanning speed of 140 mm/s and pulse duration of 150 ns. Two sets of textured samples were produced: with a frequency of 50 kHz and 2 kHz. In both frequencys, the power(%) was set at 100, 60 and 20. The effect of texturing was analyzed through microstructural characterization with tests of contact angle, roughness and scanning electron microscopy.
  • Resumo IPEN-doc 30166
    Syringe cell method to study the corrosion resistance of the UNS S32101 lean duplex stainless steel welded by the gas tungsten arc welding double fusion (GTAW-DF)
    2023 - BUGARIN, ALINE de F.S.; VIVEIROS, BARBARA V.G. de; TERADA, MAYSA; GUILHERME, LUIS H.; NEVES, MAURICIO D.M. das; COSTA, ISOLDA
    This work aims to investigate the corrosion performance of the UNS S32101 lean duplex stainless steel (LDSS) welded by the gas tungsten arc welding double fusion (GTAW-DF). In the study, six welded samples were manufactured with different welding parameters. A Syringe cell was used to characterize the electrochemical behavior of the different welded zones by potentiodynamic polarization tests in NaCl 3,5 % (w.t.) and in a solution of citric acid with addiction of NaCl to simulate the food industry. The results showed that the welding parameters tested significantly affected the corrosion resistance of the LDSS UNS S32101. Besides, a correlation was stablished between microstructure and electrochemical behavior of fusion line (FL), heat affected zone (HAZ) and fusion zone (FZ).
  • Artigo IPEN-doc 29855
    Investigation on the Effect of a Chromium-Free Sealing Treatment for the Corrosion Resistance of AA2198-T851 after Tartaric Sulphuric Anodizing (TSA)
    2023 - QUEIROZ, FERNANDA M.; BUGARIN, ALINE de F.S.; AYUSSO, VICTOR H.; TERADA, MAYSA; COSTA, ISOLDA
    The AA 2198-T851 is a third-generation Al-Li alloy developed for use in the aircraft industry. Al-Li alloys are susceptible to localized corrosion due to their complex microstructure resulting from the used thermomechanical treatment. In order to prevent localized corrosion, these alloys are usually protected by anodizing in order to avoid a corrosive environment. Subsequently, for anodizing, a sealing treatment is usually performed for parts. Some sealing treatments use hexavalent-chromiumion-containing solutions. In this investigation, a chromium-free sealing treatment in a solution with cerium ions has been carried out, and the effect on the corrosion resistance of the AA2198-T851 alloy was investigated. Hydrothermally sealed or unsealed samples were also tested for corrosion resistance for comparison reasons. The corrosion resistance of the anodized aluminum alloy, either hydrothermally sealed or in a cerium-ion-containing solution, was evaluated in a sodium chloride solution by electrochemical impedance spectroscopy as a function of immersion time. The samples sealed in a cerium-containing solution increased their corrosion resistance when compared to the hydrothermally sealed. The effectiveness of the sealing process with cerium that was observed in the electrochemical tests indicated that after the corrosive attack of the barrier layer, there was a “sealing” process of the sample surface.
  • Resumo IPEN-doc 29811
    ICC INTERCORR WCO 2021
    2022 - PANOSSIAN, ZEHBOUR; COSTA, ISOLDA; ROSSI, JESUALDO L.
    Brazil, once again, organized one of the world’s most significant corrosion events, the ICC - INTERNATIONAL CORROSION CONGRESS. In 1978, the 7th edition of the congress was held by ABRACO, in Rio de Janeiro, under the direction of our Dr. Aldo Cordeiro Dutra, chairman of the Executive Committee. To intertwine two events, the 21st ICC was held together with the traditional INTERCORR, the most representative corrosion and corrosion prevention event held in Brazil, organized by ABRACO, in its 8th edition, which included the workshop “Corrosion and Green Energy”, an event of the World Corrosion Organization (WCO). Thus, the ICC INTERCORR WCO 2021 was arranged with this strong partnership.The institutions responsible for organizing the ICC INTERCORR WCO 2021 were: the Brazilian Corrosion Association (ABRACO), the International Corrosion Council (ICC), and the World Corrosion Organization (WCO). To overcome a new post-pandemic Covid-19 reality, the event occurred virtually from July 20th to 23rd, 2021.The ICC INTERCORR WCO 2021 has become a reference for developing the industrial sector, being an excellent forum for presenting new technologies, disseminating knowledge, prospecting for brands, business opportunities and expanding relationships. Its main objective was to encourage the exchange of knowledge between researchers, technicians, professionals, and companies, whether nationally or globally.The ICC INTERCORR WCO 2021 program included the presentation of 6 plenary conferences, 19 lectures, and more than 220 technical articles by renowned specialists from different countries such as Germany, India, Egypt, USA, Portugal, Australia, Italy, Sweden, Spain, Brazil, among others.Today´s moment highlights the importance of promoting such an event in the country, aiming to find solutions to contribute to the recovery that the industrial sector needs. Maintaining the integrity of assets and minimizing operating and maintenance costs are highly relevant concerns in our daily lives, directly impacting the productive sector.Therefore, on behalf of the Executive Committee, we would like to thank all participants and members of the local organizing committee and the scientific committee. We also sincerely thank the support team for collaborating before, during and after this highly successful event.
  • Artigo IPEN-doc 29764
    A historical, statistical and electrochemical approach on the effect of microstructure in the anodizing of Al alloys
    2023 - ARAUJO, JOAO V. de S.; MILAGRE, MARIANA; COSTA, ISOLDA
    Anodizing is a well-documented surface treatment that is inserted in a complex protection system against corrosion applied to Al alloys. In the scientific literature, there are many works about this topic, which are concentrated on: (1) anodic aluminum oxide (AAO) growth mechanism; (2) anodized alloys corrosion behavior, or (3) the influence of anodizing parameters on the following steps of corrosion protection of the anodized layer. However, the effect of the microstructure on the AAO formation is not yet well established. This paper aims to review the effect of the microstructure of Al and its alloys on the anodizing process by a historical, statistical, and electrochemical approach, considering the advantages in understanding the influence of intermetallics in this process. Besides, this review brings a comparison among the number of publications and the types of alloys studied by statistical analyses. Finally, it emphasizes the importance of anodizing in the aeronautical industry, in which a great number of studied alloys are applied, mainly the 2XXX (Al-Cu) and 7XXX (AlZn) series alloys.