A5089842619- Diamond and Carbon-based Materials Research
- Force Microscopy Techniques and Applications
- Metal and Thin Film Mechanics
- Semiconductor materials and devices
- Adhesion, Friction, and Surface Interactions
- Molecular Junctions and Nanostructures
- Advanced materials and composites
- Orthopaedic implants and arthroplasty
- Tribology and Wear Analysis
- Copper Interconnects and Reliability
- Advanced Welding Techniques Analysis
- Advanced Nanomaterials in Catalysis
- High Entropy Alloys Studies
- Metal Forming Simulation Techniques
- Advanced ceramic materials synthesis
- Aluminum Alloys Composites Properties
- High-pressure geophysics and materials
- Advanced Photocatalysis Techniques
- High-Temperature Coating Behaviors
- Surface Modification and Superhydrophobicity
- TiO2 Photocatalysis and Solar Cells
- Silicon and Solar Cell Technologies
- Metallic Glasses and Amorphous Alloys
- Semiconductor materials and interfaces
- Lubricants and Their Additives
Universidade Estadual de Campinas (UNICAMP)
2024-2025
Universidade de Caxias do Sul
2015-2024
Departamento de Ciência e Tecnologia
2020-2021
Materia (United States)
2021
Pension Fund for Care and Well-Being
2020
Amorphous carbon (a-C) and several related materials (DLCs) may have ultralow friction coefficients that can be used for saving-energy applications. However, poor chemical bonding of a-C/DLC films on metallic alloys is expected, due to the stability carbon–carbon bonds. Silicon-based intermediate layers are employed enhance adherence a-C:H ferrous alloys, although role such buffer not yet fully understood in terms. The thin alloy intermediated by a nanometric SiCx:H layer was analyzed X-ray...
Diamond-like carbon (DLC) coatings show strident properties such as high wear resistance and ultra-low friction. However, a widespread use regarding energy efficiency issues is neglected due to the poor adhesion. Silicon adhesion interlayers (SiC x :H) were deposited at different temperatures from 50 500°C with hexamethyldisiloxane followed by DLC. The microstructure was analysed atomic force microscopy, scanning electron microscopy Raman spectroscopy. chemical depth profiling mapping...
Laminated metallic composites (LMCs) produced by cold roll bonding generate high plastic deformation. After the rolling process, it is essential to promote a post-heat treatment (PHT) increase adhesion, minimize hardening, and enhance formability of LMCs. In this research, effects PHT at low temperatures (250, 350, 450°C) on LMCs (STS304/Al1050/STS430) obtained were investigated. The Forming Limit Curve (FLC) mechanical properties such as ultimate tensile strength (σ_UT), yield (σ_Y),...
Hydrogenated amorphous carbon thin films (a-C:H) have attracted much attention because of their surprising properties, including ultralow friction coefficients in specific conditions. Adhesion a-C:H on ferrous alloys is poor due to chemical and physical aspects, avoiding a widespread application such film. One possibility overcome this drawback depositing an interlayer—an intermediate film—between the carbon-based coating substrate improve interaction adhesion. Based this, interlayers play...
The poor adhesion of carbon thin films was the main restriction for its massive application in recent years. Physicochemical interaction improvement at interface between substrate and film is one most important fields research to overcome such problem. From a chemical point view, oxygen seems be major issue control. In this work, influence base pressure prior deposition process on tribological behaviour studied. Rockwell C scratch tests were performed qualify failures adhesion. Chemical...
In dry sliding, the coefficient of friction depends on material pair and contact conditions. If operating conditions remain unchanged, is constant. Obviously, we can tune by surface treatments, but it a nonreversible process. Here, report active control forces TiO2 thin films under UV light. It reversible stable be tuned/controlled with light wavelength. The analysis atomic force microscopy signals wavelet spectrograms reveals different mechanisms acting in darkness UV. Ab initio simulations...
Energy dissipation associated with frictional damping mechanisms owing to van der Waals (vdW) forces by induced polarizability at the sliding interface of a-C:H thin films.
Silicon-based materials are widely applied in micro- and nanoscale devices, such as nano-electromechanical systems (MEMs NEMs, respectively). However, the nanofriction behavior of is still an issue that influences or hinders some applications. Recently, a sliding-dependent friction mechanism was accessed, by simulation hydrogenated silicon surfaces, which forces increase during sliding. The experimental evaluation this phenomenon lacking, well confirmation ambient air conditions, related to...
For the first time, polarizability and electronegativity are related as atomic descriptors for understanding influence of physicochemical factors on nanoscale friction.
A comprehensive study on the effects of sterilization methods UHMWPE is reported, highlighting surface properties and biological outcomes.
The low adhesion of amorphous carbon (a-C) films on ferrous alloys has restricted massive industrial application since their development, restricting to mechanical and electromechanical components. Although different mechanisms have been raised describe the a-C film adhesion, chemical affinity role oxygen at interfaces are key issue. Nevertheless, a quantitative approach considering adsorption strength/base pressure relationship is still not proposed, which would be special interest in...
Lateral force microscopy (LFM) is an established technique to assess friction forces at the nanoscale. Nanoindentation followed by unidirectional sliding (NUS) also used evaluate micro/nanoscale. However, comparative studies between NUS and LFM evaluating experimental results different scales are still missing. In this work, a-C:D/H a-C:H thin films with [D]/[C] [H]/[C] contents were analyze LFM. The show that behavior assessed these two techniques in same. correlation measured depends...
Abstract Active control of nanotribological properties is a challenge. Materials responsive to external stimuli may catalyze this paradigm shift. Recently, the nanofriction thin film modulated by light, ushering in phototribology. This frontier expanded here, investigating photoactive nanoparticles lubricants confer similar functionality passive surfaces. Quartz‐crystal microbalance (QCM) employed assess phototribological behavior aqueous suspensions titanium dioxide nanoparticles. A...
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