Evaluation Of Adhesive Strength Research Articles

Adhesion strength evaluation for plasma-sprayed coatings based on intensity of singular stress

Adhesion strength evaluation for plasma-sprayed coatings based on intensity of singular stress

Examination of plastic region size and two singular stress field on the ISSF adhesive strength evaluation method

In an adhesive joint under certain conditions, the adhesive joint strength is larger than the bulk adhesive strength. In this study, the fracture of adhesive joints by using the elastic-plastic behavior is considered. Then, the validity of evaluating the adhesive strength by two ISSFs based on the elastic analysis is discussed. Even when the butt joint strength is larger than the bulk adhesive strength, the small-scale yielding is occurred. Therefore, it is shown that the ISSF strength evaluation method is appropriate.

Evaluation of Adhesive Bond Strength, and the Sustained Release of Fluoride by Chitosan-infused Resin-modified Glass Ionomer Cement: An In Vitro Study

Aim and objectiveTo evaluate the adhesive bond strength, and sustained release of fluoride in chitosan (CH)-infused RMGIC.Materials and methodsTwenty caries-free human permanent premolar teeth, extracted for orthodontic purposes, were cleaned and stored in thymol solution. The crown of each tooth was cut into two halves and RMGIC (n = 10) and CH-infused RMGIC (n = 10) was placed between the two halves of the crown. The tooth was then stored in 10 mL of artificial saliva for a period of 30 days. The fluoride levels of the saliva were checked on the 15th- and the 30th-day using ion chromatography. The adhesive bond strength was checked on the 30th day using a universal testing machine.ResultsThis study has shown that the bond strength of RMGIC was not affected by the inclusion of CH in it. Whereas, the sustained fluoride release of CH-modified RMGIC indicated that the fluoride release of CH-RMGIC was 8.47% >RMGIC at the end of 15 days, and, 39.68% >RMGIC at the end of 30 days.ConclusionThe inclusion of CH in RMGIC does not alter its bond strength, while it does cause a greater release of fluoride.Clinical significanceIn progression with these results, the inclusion of CH in RMGIC could provide desirable properties like mechanical reinforcement effects and catalytic effects on the fluoride release and growth factors.How to cite this articlePatel A, Dhupar JKMS, Jajoo SS, et al. Evaluation of Adhesive Bond Strength, and the Sustained Release of Fluoride by Chitosan-infused Resin-modified Glass Ionomer Cement: An In Vitro Study. Int J Clin Pediatr Dent 2021;14(2):254–257.

Evaluation of adhesion strength of TiN layer applied on 316L substrate by electrophoretic deposition

Evaluation of adhesion strength of TiN layer applied on 316L substrate by electrophoretic deposition

Improving the Water Barrier and Anticorrosion Performances of Epoxy-Chitosan Coatings via Silane Modification

The effect of silane modifiers (aminotrimethoxy silane, ATMS, tetraethoxy silane, TEOS and trimethyl hexadecafluorosilane, TMHDFS) on the water absorption and anticorrosion properties of epoxy-chitosan coatings was investigated. BET surface area, particle size, surface morphology and physico-chemical properties analyses of synthesized chitosan were conducted. BET analysis showed the synthesized chitosan has surface area of 17.195 m2/g, pore volume of 0.008 cm3/g and pore size of 1.688 nm. Average particle size of 2.252 μm was determined. The wettability results showed they were hydrophobic. Degree of deacetylation and percent crystallinity were estimated from FTIR and XRD spectra to be 33.56% and 59.24%, respectively. The percent chitosan yield was calculated to be 72.47%. Subsequently, epoxy-chitosan and silane-modified epoxy-chitosan coatings were formulated and compared to plain epoxy coating. The SEM images of the coatings clearly showed that the silane-modified epoxy-chitosan coatings were more compact than the plain epoxy and epoxy-chitosan coatings. Interestingly, the EIS, OCP and immersion techniques showed epoxy-chitosan/TMHDFS coating exhibited the highest anticorrosion and the lowest water absorption performance, respectively. These results were corroborated by evaluation of adhesion strength. The obtained results have demonstrated that TMHDFS-modified chitosan could be employed for effective low water absorption and anticorrosion epoxy coatings billed for protection of marine structures.

Evaluation of bacterial adhesion strength on phospholipid copolymer films with antibacterial ability using microfluidic shear devices.

Biomimetic phospholipid copolymer films are known to possess antifouling properties against protein adsorption and biofilm formation. However, the interactions between bacterial cells and material surfaces are not fully understood. This work investigated the bacterial adhesion strength of phospholipid copolymer films using a shear stress-tunable microfluidic device. The copolymer, comprising 2-methacryloyloxyethyl phosphorylcholine (MPC), 3-methacryloxypropyl trimethoxysilane (MPTMSi), and 3-(methacryloyloxy) propyl-tris(trimethylsilyloxy) silane (MPTSSi), formed crosslinked films on glass substrates; the thickness of the coating film was controlled by the polymer concentration during dip-coating. Polymer films with two typical thicknesses, 20 and 40 nm (denoted as C-20 and C-40, respectively), were prepared on the bottom wall of the microfluidic device. After seeding S. aureus in the microfluidic device, several shear stresses were applied to evaluate the adhesion strength of the polymer films. S. aureus was found to have weaker adhesion strength on the C-40 surface than on the C-20 surface; numerous bacterial cells detached from the C-40 surface on application of identical shear stress. To mimic the presence of plasma protein, fibrinogen (Fg) was introduced into the device before performing the bacterial adhesion assay. The results showed that the adsorption of Fg promoted S. aureus adhesion and strong interactions under shear stress. However, the adhesion strength of S. aureus did not affect the Fg adsorption for both the C-20 and C-40 surfaces. Using the shear stress-tunable microfluidic device, we found that the adhesion of S. aureus on the thicker and softer phospholipid copolymer was weak, and the cells easily detached under high shear stress.

スカーフ継手における特異応力の強さ(ISSF)を用いた接着強度の評価法

スカーフ継手における特異応力の強さ(ISSF)を用いた接着強度の評価法

Adhesive strength evaluation of stepped-lap joint based on the intensity of singular stress field (ISSF)

Adhesive strength evaluation of stepped-lap joint based on the intensity of singular stress field (ISSF)

Adhesive strength evaluation of scarf joint based on the intensity of singular stress field (ISSF)

Adhesive strength evaluation of scarf joint based on the intensity of singular stress field (ISSF)

Evaluation of Tensile Adhesion Strength in Simulated Dust Cakes on Fabric Filters

AbstractBased on the results of a 3D simulation of cake formation on characteristic filter models for fabric filters with different surface structure, the tensile adhesion strengths in simulated dust cakes are evaluated on the basis of the resulting inhomogeneous local porosity distribution of the particle packing by calculating fracture points at a balance between adhesion and detaching strengths. Both the evaluation method itself and the evaluation results for a computation example are presented and discussed. A significant proportion of fracture points are found in deeper levels in the filter medium, and the distribution of tensile adhesion strengths there differs strongly from the distributions in top levels of the filter medium. The fracture points in the top layer of the filter medium, where a special surface texture is generated, can contribute a considerable part of the tensile adhesion strengths over the whole filter area.

Experimental Evaluation of Adhesion Strength of 3D Printing on Cotton Fabric in Shear Mode

Post-consumer plastics become an issue to the environment due to their stable and non-biodegradable nature. Their management is essential today and starts from the source of utility through segregation to the place where proper care can be taken place that includes landfills or energy recovery areas or place of recycling. The present work is a step towards the development of an environmentally friendly and sustainable depolymerization method of bisphenol A-based polycarbonate. Chemical recycling has come up with various advantages in comparison to the traditional recycling methods for plastics. The reaction has been performed with environmentally friendly green solvents and also with green reagents like alumina and montmorillonite clays.

A novel evaluation of shock absorption and adhesive strength under shear impact loading

ABSTRACT The authors study shock absorption characteristics and their measurement methods because test standards and specifications for shock absorbing adhesives are not clearly established. Especially, microscale shock absorbing adhesive characteristics are important for mechanical properties of small-sized mobile electronics with slim, bezel-less design. For this purpose, a piezoelectric force sensor is utilized to evaluate impact response of various adhesives under ball drop impact due to high-frequency data acquisition. Next, the evaluated impact responses are compared with dynamic mechanical analysis results to confirm the viscoelastic material behavior of adhesives. In addition, the impact response is proportionally correlated with the damping factor. In order to characterize both shock absorption and adhesive strength simultaneously, a novel test apparatus for shear impact is devised based on the previous test. The correlation between two mechanical properties is determined by analyzing the change of the impact force transmitted through the adhesive. The degradation of the adhesion strength is described by the damage model, which estimates its change before detachment. The proposed experimental mechanics not only enables a concurrent evaluation of adhesion strength and shock absorption but also assesses required adhesive materials for delicate electronic components.

Evaluation of interlayer adhesion strength of asphalt pavements reinforced with fiberglass grid

Evaluation of interlayer adhesion strength of asphalt pavements reinforced with fiberglass grid

Adhesive strength evaluation for three-dimensional butt joint in terms of the intensity of singular stress field on the interface outer edge

Our previous studies analyzed the adhesive strength of butt joint systematically in terms of the intensity of singular stress field (ISSF) by using two-dimensional modeling. In consideration of the actual specimen geometry, in this paper, the adhesive strength of butt joint is analyzed by using three-dimensional modeling. A mesh-independent numerical method combined with the finite element method (FEM) is used to calculate the ISSF. The ISSF distribution on the interface outer edge is analyzed, the effect of adhesive thickness is investigated. The ISSF at the interface vertex is analyzed by using a small fillet instead. The difference between 2D and 3D models for adhesive strength evaluation is discussed. The usability of 2D modeling is investigated.

Experimental evaluation of interfacial adhesion strength of cold sprayed Ti-6Al-4V thick coatings using an adhesive-free test method

Cold spray (CS) is a rapidly growing solid-state additive material deposition technique often used for repair of high-value metallic components. This study aims at evaluating the interfacial adhesion strength of cold sprayed Ti-6Al-4V (Ti-64) coatings deposited onto Ti-64 substrates for repair applications. An adhesive-free test method, referred as modified Collar-Pin Pull-off Test was developed based on Sharivker's (1967) original design, in order to overcome the limitations of existing test approaches (both adhesive-based and adhesive-free). This method was designed to allow measurement of adhesion strength of high strength coatings such as CS Ti-64, where adhesion strength is higher than 70–90 MPa. A parametric study was performed to assess the effect of coating thickness, scanning speed, track spacing, toolpath pattern, and substrate surface preparation on the coating adhesion strength. A finite element model was also used to evaluate the stress distribution during the pull-off test, and to check the validity of the proposed test method. The proposed adhesive-free test method was found to be capable of measuring coatings with adhesion strengths beyond the upper limit of conventional adhesive-based methods such as ASTM C633. Among the investigated cases, the highest value of coating adhesion strength was measured around 122 MPa, in the case of CS Ti-64 deposited on ground Ti-64 substrates.

New adhesive strength evaluation method based on the singular stress field considering three-dimensional geometry

Adhesive joints are widely used although different materials properties cause the singular stress field whose intensity is controlled by the adhesive joint geometry. Our previous studies showed that debonding strength can be expressed as a constant value of the critical intensity of singular stress field (ISSF) by applying two-dimensional modelling. By considering the real adhesive geometry, in this study, the ISSFs along the interface edge of three-dimensional prismatic butt joints are considered by varying the adhesive thicknesses. It is found that the critical ISSF in 3D modelling is almost constant independent of the adhesive thickness. The magnitude and position of the maximum ISSF are discussed by varying the corner fillet radius in comparison with two-dimensional modelling.

DLC-coating Application to Improve the Durability of Ceramic Tools

The work is devoted to the experimental study of the efficiency of Arc-PVD and PACVD industrial technologies for the application of diamond-like carbon (DLC) coatings on ceramic cutting plates based on Al2O3 + TiC to increase the wear resistance of the tool when turning of bearing hardened steel 102Cr6. The authors conducted a set of studies and tests as the study of the structure of DLC coatings (correlation between sp3 and sp2 bonds) using photoelectron spectroscopy; evaluation of roughness, microhardness and adhesive bond strength of DLC coatings with the ceramic base; study of coated ceramics wear under fretting conditions; and experimental evaluation of the effect of DLC coatings on the resistance of ceramic plates during turning of hardened steel. The durability of ceramic plates was increased by 1.6 times by applying PACVD DLC coatings. A slightly smaller effect in 1.4 times was achieved by applying DLC coatings using Arc-PVD technology.

Evaluation of Ice Adhesion Strength on the Oxidation of Transmission Line ACSR Cable

Ice accumulation on Aluminum Conductor Steel Reinforced(ACSR) cable during winter is an important matter in terms of safety, economy, and efficient power supply. In this work, the ice adhesion strengths of ACSR cable oxidized during different periods(7 years oxidized and 15 years oxidized) are evaluated. At first, a plate type dry oxidation standard specimen, whose surface characteristics are similar to those of ACSR cable, is prepared. Dry oxidation standard specimens are heat-treated at 500 °C for 20, 60, and 120 minutes in order to obtain different degrees of oxidation. After the dry oxidation, surface properties are analyzed using contact angle analyzer, atomic force microscopy, spectrophotometer, and gloss meter. The ice adhesion strengths are measured using an ice pull-off tester. Correlations between the surface properties and the ice adhesion strength are obtained through a regression analysis indicating a Boltzmann equation. It is revealed that the ice adhesion strength of 15- year oxidized ACSR cable is approximately 8 times higher than that of ACSR-bare.

Influence of Shear and Micro-Shear Tests on Adhesive Resistance and Fracture Types of Direct Restorative Systems in Dentin

The aim of this study was to evaluate the influence of shear and micro-shear tests on adhesive resistance and on defects in restorations in human dentin. The teeth were sectioned and embedded. The dentin surface was treated with universal system adhesive and the samples were divided into two groups. In the first, composite resin pins were fixed with 1 mm diameter and in the second, pins with 2 mm. After mechanical tests the samples were taken to the SEM for analysis of fractures. Tensile strength on G1 was 16 MPa and on G2 20 MPa. The fractures occurred after shear were mostly mixed and cohesive in dentin. On micro-shear adhesive and mixed, no cohesive. It can deduce that, the diameter of the pin influenced the adhesive resistance and the type of failure. Therefore, for evaluation of adhesive strength in dentin the test indicated is micro-shear.

Application of a Novel Modification of the Microbond Test for Evaluation of Adhesive Bond Strength Between Fiber Posts and Dual-Cure Dental Resin Cement.

BackgroundWhile several tests can be used in the laboratory evaluation of composite resin-based cement materials, the push-out test remains the most prevalent. Due to difficulties in sample preparation, as well as a highly complex procedure, we attempted to develop an alternative method for testing the bond strength of dental resin cement materials.Material/MethodsNinety-six experimental samples of 2 dual-cure resin cements and 1 fiber post system were prepared for the 2 testing procedures: the push-out test and the modified Microbond test. The degree of monomer conversion was measured by Fourier-transform infrared spectroscopy.ResultsThe push-out test results indicated that the bond strength of dual-cure resin cement differs depending on the tooth root region to which it is applied (p<0.05), In addition, our findings show that Variolink II exhibits a much lower bond strength relative to RelyX ARC. These findings were confirmed by the modified Microbond test results. The monomer conversion rate results indicate average conversion rates of 85.81% and 61.35% for RelyX ARC and Variolnik II, respectively.ConclusionsOur study confirms the practical utility of the modified Microbond test in the assessment of bond strength of dental cement resin-based materials. The proposed test method is particularly useful given that, relative to the push-out test, it requires a much smaller number of preparation and execution steps, thus reducing the potential for introducing errors, while increasing the reliability of the obtained findings.