Papers by Keyword: Wettability

Abstract: The use of hybrid nanofluids aimed to improve the exceptional qualities of fluids, including adsorption, viscosity, stability, and interfacial tension. Although several surfactant changes utilizing hybrid nanomaterials have been documented, their wider application has been hindered by the material's stability and processing challenges. The purpose of this study is to use the liquid phase exfoliation technique and examine the properties of the recently created hybrid nanofluids. This paper investigates the mechanisms of how hybrid nanofluids (HNF) composed of Graphene nanoplatelet (GNP) & SiO₂ with various surfactants such as Gum Arabic (GA) and Sodium Carboxymethyl Cellulose (SCMC) could improve EOR through adsorption of nanoparticles, improve viscosity, Interfacial tension (IFT), and wettability contact angle. Based on the results, using the hybrid nanoparticles decreases the IFT between oil-water interface from 39.700 mN/m for brine to 38.466, 37.582, 35.609 mN/m, for Control HNF, GA HNF, and SCMC HNF respectively. The adsorption of nanoparticles mechanism occurs and peaks during a 12-hour to 24hour period. Furthermore, the findings on the performance of hybrid nanofluid have increased the viscosity from 0.317cP (brine) to 3.638cP (GA) and 3.556cP (SCMC) nanofluid. When nanoparticles are introduced into reservoirs, they interact with rocks and crude oil via rock absorption, potentially improving the recovery rate of oil by changing wettability and influencing the efficiency of water-transfer to oil in several improved oil recovery methods. The contact between the rock surface, nanofluid, and oil was shown to be reduced by 29.47% and 59.12%, as seen by the contact angle of the oil droplet on the rock surfaces. The phenomenon occurs because nanoparticles are attached to the interface of rock, oil, and brine.

Abstract: The noise and vibrations generated by equipment and machinery during everyday life and industrial activities can affect both human and machine operations. Specifically, research aimed at suppressing vibrations and noise to enhance the energy efficiency of machinery is becoming increasingly active. In this study, magnesium was selected as the material for vibration damping. The detrimental effects of magnesium are improved by the addition of small amounts of Mn and Zn. A composite material was fabricated using magnesium, which has excellent vibration damping properties, and carbon steel (S45), which has superior mechanical properties. Magnesium alloys with Zn additions of 1, 3, and 5 wt.% were produced to enhance the corrosion resistance and strength of magnesium. Contact angle experiments were conducted to measure the wettability of the magnesium alloys. The contact angle was measured using the sessile drop method. The magnesium alloys showed a decreasing trend in contact angle with increasing zinc content. To explain the decrease in contact angle in Mg-Zn alloys, microstructure and compositional analyses were performed. First, Mg-Fe and Zn-Fe phase diagrams were investigated. The Mg-Fe system was found to contain no intermetallic compounds. In Zn-Fe interactions, Zn appears to form a metallic bond with Fe. The presence of the Γ phase at the interface between the magnesium alloy and S45 indicates that Zn has diffused from the magnesium alloy into both the magnesium alloy and S45. The Γ phase, considered a compound of Fe₃Zn₁₀, improves wettability between particles due to the formation of intermetallic compounds. Therefore, it was inferred that the wettability of the magnesium alloy improved. Additionally, improved wettability is expected to contribute to better adhesion processes and potentially increase interfacial shear strength.

Abstract: The surface wettability of metallic biomaterials significantly influences the biological response of biomedical implants. However, the optimal degree of wettability depends on the specific coating or surface treatment applied to the biomaterial. Researchers have widely utilised hydroxyapatite coatings to modify implant surfaces to enhance bioactivity, biocompatibility, and osseointegration. This review article discussed the impact of hydroxyapatite-doped coatings on the surface wettability of metallic biomaterials. A systematic search of Scopus and Web of Science databases was conducted to review recent studies investigating the wettability and biological response of hydroxyapatite-doped coatings applied through standard implant surface deposition techniques. Results reveal that hydroxyapatite-doped coatings are typically hydrophilic and have higher surface energy than uncoated hydrophobic metallic surfaces. The hydrophilic nature promotes better interaction with biological fluids, resulting in cell adhesion and proliferation. The rough and porous surface increases wettability as fluid can easily penetrate the craters. Further research may elucidate the complex connectivity of deposition method process parameters with surface wettability and biological outcomes. This review briefly overviews current research on hydroxyapatite-doped coatings and their effects on surface wettability and biointegration.

Abstract: The current study proposes to investigate the thermal, wettability and mechanical properties of a low temperature SnBi solder. The main aim is to investigate the performance of the SnBi solder alloy with different Bi composition. The study also establishes the relationship between melting temperature, spreading area and tensile stress of the SnBi with different Bi composition at different low reflow temperatures. The thermal and wettability tests are conducted experimentally, while the mechanical test will be analysed via finite element analyses (FEA). The single shear lap test method was adopted for the simulation. The thermal properties of the SnBi solder are investigated using the differential scanning calorimeter (DSC). The reflow temperature selected ranges from 160 °C to 220 °C to accommodate the purpose of low temperature soldering. Wetting test results showed that spreading area of Sn48Bi solder alloy increased to 28.1 and 42.88 at 180 °C and 210 °C respectively. The increase in the Bi composition reduced the tensile strength regardless of the increase of the reflow temperature. The preliminary results commend the characteristics of the SnBi solder as a possible alternative to the Pb solder.

Abstract: Hastelloy is a nickel-chromium-molybdenum-iron-based alloy and a member of the ‘superalloy’ family. Hastelloy has exceptional properties like high strength, wear resistance and high-temperature stress-corrosion resistance. Therefore, Hastelloy is used in gas turbines, power plants, metal injection molding, etc. Many industrial applications are related to the properties of the surface. Wettability is a key surface property that affects applications like lubrication, adhesion, coating, heat conduction, etc. Laser Texturing is an excellent method to modify the surface properties of materials like metal, polymers and ceramic. In the present study, a carbon dioxide laser created unidirectional textures on Hastelloy (C22, C276, X). Different sets of unidirectional textures were formed by changing the laser power and frequency. Various roughness parameters were compared for every laser parameter. In this paper, the effective change in wettability properties of Hastelloy (C22, C276, X) after the Laser texturing process for a range of power and frequency were studied under DI water and glycerol as test fluids. Results show that the contact angle of the test fluid increases as the laser power increases, and the contact angle decreases as the laser frequency increases for all three superalloys. The surface energy of a given set of samples was also measured using the recorded contact angle of DI water and Glycerol by the OWRK equation. Similar trends were found in surface energy for all three Hastelloy.

Abstract: Natural fibers are increasingly used in the polymer industry as bio-composites for a wide range of applications, such as the interior part of the automobile, interior material boards, decking panels, and many others. The presence of cellulose, which is hydrophilic in nature, lessens the mechanical properties of the bio-composites by increasing water uptake into the composites or also may affect the interfacial bonding between the polymer matrix and the fibers because the matrix is hydrophobic. The former may occur due to the surface of the bio-composites being highly exposed to water sources, e.g., high humidity in the air, rainwater, and many more. Thus, an additional layer on the surface of the bio-composites needs to be applied to protect the surface from water sources. The coating may be used for decorative, protective, or both purposes. This study aims to investigate the performance of polymer coating on a bio-composite substrate. The coating solution, chitosan-pectin-calcium chloride (CPC) solution was prepared, and the compatibility and wettability of the coating solution with the polymer-based bio-composites substrate were evaluated. The substrate was dipped into the coating solution for two minutes and hung to allow the excess coating solution to drop while drying the substrate. The performance of coating on the bio-composite substrate is evaluated by measuring the contact angle θ and average maximum bond strength σ_b of the sample with the different numbers of coating layers. It is found that the wettability of the contact angle indicates a lower contact angle for two-layer compared to one layer of the CPC coating due to the hydrophilicity of the coating materials.

Abstract: This research aimed to study the effects of Ni content on melting behaviors and wettability of SnBiAgNi lead-free solder. Sn-58Bi-0.05Ag was used as the base solder, and Ni was then put in by 0.05, 0.10, 0.50 or 1.00 wt%. Solidus and liquidus temperatures of the solder alloys were examined to study melting behaviors. The Ni content changed the solidus and liquidus temperatures, and Sn-58Bi-0.05Ag-0.10Ni possessed the lowest solidus and liquidus temperatures. Sn-58Bi-0.05Ag-0.10Ni also provided the narrowest pasty range. Wettability of the solders on the copper substrate was expressed in terms of spread factor. The addition of Ni improved the wettability of the base solder, and Sn-58Bi-0.05Ag-0.10Ni provided the highest spread factor.

Abstract: The ability to promote rapid osseointegration is an important criterion on the titanium implant surface. This performance is greatly determined by the roughness, wettability, and composition of the implant surface. This study aims to investigate the oxide layer formation and wettability on the EDM-titanium implant surface engineered by different micro-finishing methods (i.e. mechanical, physical, and chemical processes). The oxide layer formation was investigated by observing the wt% of oxygen formed while the wettability criterion was studied by determining the contact angle between the liquid and solid surface. The result reveals that the oxide layers formed on the sample surface, excepting Sulfuric acid (H₂SO₄) 95%-etched, show an interaction with the surface roughness and its wettability. The smoother the surface roughness of the sample, the lower the percentage of the oxide layer and the contact angle formed on the sample surface. In this aspect, the ultrasonic cleaning benchmark has the highest percentage by altering 18.84% of the oxide layer formed by the EDM process while the decrease of 75.89% generated by the H₂SO₄-etching is the lowest one. On the other hand, the higher the percentage of the oxide layer formation, the lower the wettability of the sample surface. In this aspect, the ultrasonic cleaning benchmark has the lowest wettability with a contact angle of 124º (hydrophilic) while HCl-etching is the lowest with 45º (hydrophobic). The results are notable that the ultrasonic cleaning method is able to alter wt% of the oxygen on the EDM-titanium implant surface, whereas the acid etching method can be recommended as a worthy method of the surface finishing for the semi-permanent type of implant.

Abstract: Titanium dioxide (TiO₂) has been exploited extensively as it shows remarkable performance in photocatalytic applications. TiO₂ thin films can be deposited onto window glass which is workable for self-cleaning applications. In this article, we have studied the role of substrate temperature for spray pyrolysis (SP) of TiO₂ thin films for studying self-cleaning applications. For thin film deposition, TiO₂ sol is prepared by the sol-gel synthesis technique. The samples are deposited at room temperature and 250 °C, respectively. The samples are characterized via Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), and UV-Vis spectroscopy to determine the morphology, surface roughness, and optical properties of the thin films. SEM and AFM results show that samples deposited at 250 °C (pre-heated samples) have uniform size distribution, and defined grain boundaries, respectively. The results also show that the pre-heated sample is highly transparent in the visible region of the solar spectrum when analyzed by the steady-state UV-Vis spectrophotometer. The wettability of the prepared thin films is measured, and the results show that the pre-heated sample shows a hydrophilic character. The self-cleaning property of prepared thin films is evaluated by the photodegradation of Rhodamine B dye. It is observed that the pre-heated substrates show better photoactivity in presence of UV light irradiation. Hence, due to their hydrophilic nature and better photoactivity, these pre-heated thin films deposited by spray pyrolysis can be employed as efficient coatings for self-cleaning glass applications.

Abstract: Poly (glycerol sebacate) pre-polymer was synthesized and methacrylated to different degrees (PGSm-0.1, PGSm-0.2, PGSm-0.4) to impart processability using radiation technology. Spectroscopic analyses (FTIR and ¹H NMR) confirmed the presence of ester linkage in the poly (glycerol sebacate) chain and the methacrylate group in the derivatives. The degree of methacrylation (DM) computed from the ¹H NMR signal integration ranged from 0.1 to 0.4. The molecular weight and polydispersity increased with an increase in DM. The DSC thermograms suggested better elastomeric properties at ambient temperature, while the TGA showed no significant shift in the degradation parameters of PGS upon methacrylation. Electron beam curing of the PGSm samples was employed, and the resulting films were characterized for gel content, surface topography, and wettability. The crosslinked PGSm-0.2 and PGSm-0.4 samples exhibited high gelation at doses 5-50 kGy. However, no gelation above 15 kGy occurred in PGSm-0.1, suggesting that main chain scission reactions prevailed. The surface properties of the films obtained from the AFM and contact angle measurements revealed high surface roughness and wettability.