Measurement of adhesive strength between the epidermal and inner tissues of plant stems using a tensile tester.

Effect of Roughness and Surface Topography on Adhesion of PVB to AA2024-T3 using the Blister Test

Abstract— Electrophoretic deposition of phosphor particles onto substrates is used in the manufacturing of screens for advanced display applications. The effects of deposition conditions on the adhesive properties of electrophoretically deposited phosphor coatings were investigated. The adhesion was measured with a gas‐jet tester which utilizes a short pulse of nitrogen gas to remove phosphor particles from the substrate. The percentage of phosphor particles remaining on the substrate after the test was used as a qualitative measure of adhesion strength, whereas the average diameter of the “ring” of particles removed was correlated to a quantitative measure of the adhesion strength. It was found that the adhesion strength was independent of applied voltage, conductive coating on the substrate, deposit thickness, phosphor concentration, and post‐deposition treatment with water and MgO top coating. The adhesion strength was enhanced by post‐deposition baking (at 425°C) and increasing the water content of the deposition bath. The adhesion strength is also dependent upon the type of phosphor deposited and exposure of the deposits to humidity.

The adhesive force is one of the most important properties that affect asphalt binder’s all performance in pavement. Styrene-Butadiene-Rubber (SBR) latex has been used to improve the pavement performance in low temperature for a long time. In this paper, a systematic adhesive force testing procedure based on JG/T 507-2016 and pull-off strength test was employed to investigate the interfacial interaction and adhesion strength between asphalt binder and minerals. Results indicated that different emulsifier and SBR content have a great influence on low temperature adhesion performance of SBR latex modified asphalt emulsion binders. It is noteworthy that the trends of adhesive force enhanced obviously as the value of SBR content increased, however, modified asphalt emulsion with different SBR presents different maximum value of adhesive force strength which means that an optimum proportion exist in SBR modified KLMY AH-70 asphalt binders.

Decohesion of thin films in a multi-level metal IC device is an important reliability concern in semiconductor fabrication. In this study we report measurement of film stress and adhesive bond strength between films used to fabricate a two-level metal VLSI device. The device structure was simulated on Si wafers by sequential deposition of blanket films of LPCVD glass, aluminum, bilayer plasma TEOS interlevel dielectric, and aluminum. Film stress was calculated from wafer bow measurements and adhesive strength was measured using a micro-peel test. Our measurements for all the interfaces showed strong interfacial bonding, greater than the fracture strength of silicon. We also identified that the interface between two layers of plasma TEOS interlevel dielectric can be affected by processing conditions. To insure the robustness of the device structure, the adhesive strength of this interface was studied as a function of various processing parameters. Both individual and cumulative stresses for the device films were measured. The calculated intrinsic peel forces show that spontaneous adhesion failure at the device interfaces is unlikely for optimized processing conditions.

Chapter 5 - Hard/soft combinations based on thermoplastic elastomer and a rigid thermoplastic polymer: Study of the adhesion strength

Peeling of adhesive tape from hu-man skin can cause pain and trauma. The effects of the peel angle, peel rate, dwell time, subject, and order of testing were examined. Adhesive tape was peeled from the volar forearms of four human subjects. The tape was 25.4-mm-wide Durapore by 3M. The rates ranged from 100 to 10,000 mm/min, the peel angle from 90 degrees to 180 degrees, and the dwell time from one to 15 min. The tensile testing machines'recorded the peel force and the displacement of the end of the tape. A range of maximum and average peel force values was observed. The peel force tended to be minimum for a peel angle around 150 degrees in most cases. As the peel rate was increased, the peel force generally tended to increases lightly, but the relationship was erratic. As the dwell time increased, the peel force increased and then settled down. Of the subjects tested, the skin of the oldest subject experienced the most displacement and highest peel forces(the maximum force over all tests was 3.6 N). The peel force tended to increase with repeated peeling from the same skin site. Compared with peeling from a rigid substrate such as steel, the peel force from skin was lower. The results improve understanding of the factors affecting the peel force, which has been correlated previously with trauma caused by peeling adhesive tape from skin.

A single-cell analysis of the Arabidopsis vegetative shoot apex.

The adhesion strength of copper layers on TaN barrier layers decreases from 19.5 to 10 gf with annealing at 400°C. A much lower stress layer can be obtained when a seed layer is deposited on a TaSiN barrier layer. The adhesion strength is as high as 35 gf and is not changed by annealing. The critical pressure for delamination at the barrier layer/low dielectric (ɛ) layer interface decreases from 350 to when ɛ is reduced from 3.3 to 2.7 in an SiOC interlayer. That is, better adhesion strength can be attained when an interlayer with a higher dielectric constant is used. © 2003 The Electrochemical Society. All rights reserved.

Adhesion of advanced overlay coatings: mechanisms and quantitative assessment

It has been well known that the keeping quality of sausage products is closely related with the degree of adhesion of meats to the casing. However, neither the method of measuring the adhesion nor its mechanism has been studied. The present study is undertaken in order to make clear how to estimate the degree of adhesion. The results obtained are as follows. 1) To estimate the degree of adhesion, two methods, namely, the measuring of adhesion strength and that of weight of meat attached to films are employed. Adhesion strength is measured by a tensile adhesion tester designed by the present author (Fig. 1). 2) The tensile adhesion tester is consisted of 4 parts which are a tensile instrument, a tension meter, an amplifier and a recorder. In its tensile adhesion tester, an electric tension meter combined with an amplifier are used in order to measure even a slight tensile strength. 3) No change of strain obtained by the electric tension meter is found during the repeated measurings when 100g weight is hanged (Fig. 6b). 4) The best condition in measuring adhesion strength is found as follows; Sample width is 3cm, measuring temperature is fixed at 30°C, the peeling angle is 90°, and the peeling direction is clockwise (Table 1), (Figs. 9, 10). 5) It has been found that nearly same meat weights attached to the films is obtained by measuring in various parts of the casings of fish sausage and Kamaboko, moreover, that percent of standrad deviation are 9.0% (Fish sausage), 5.9% (Kamaoko). (Table 4).

Aircraft icing seriously jeopardizes flight safety. The design of aircraft anti-icing/de-icing systems requires a thorough understanding of the adhesion between the ice and the substrate. In this research, an experimental device that can be housed within a wing is designed and constructed. Simulation analysis of the interfacial stresses is performed, which reveals that increasing the load and the interface size led to a deterioration in the uniformity of stresses at the interface. In addition, the ice layer does not undergo cohesive damage during the tests. The normal ice adhesion strength is evaluated in an icing wind tunnel using the methodology outlined in this paper. Glaze ice exhibits an increase in normal adhesion strength at lower temperatures, whereas the trend is reversed for rime ice. The minimum adhesion strength occurs near the medium volume diameter (MVD) of 30 µm. Furthermore, the normal strength is significantly enhanced by increase in wind speed and surface roughness, as well as by surface painting. The adhesion strength of aluminum substrates to ice is greater compared to titanium and stainless steel. Compared to shear adhesion strength, normal adhesion strength is less sensitive to various influencing factors. The proposed experimental framework provides precise measurement of normal adhesion strength of impact ice in the icing wind tunnel.

A theoretical model is proposed to study how various mechanical factors, such as the peel rate, the thickness, and the viscoelastic properties of the adhesive and photopolymer layers, control the peel force in a peel-apart imaging film. Based on this model, several strategies are proposed to maintain a given level of the peel force while reducing the peel rate. Our analysis shows that the peel force is not a monotonic increasing function of the peel rate. Instead, the maximum peel force occurs at some intermediate peel rate which depends on the ratio Y∞ /Y0, where F∞ and Y0 are the long and short time relaxation moduli of the adhesive, respectively. Predictions of this theoretical model are then compared with experimental results. These experiments were performed under different temperatures and with typical peel rates.

A study of resistivity, adhesive strength, and residual stress measurements which were made on 450 AA Cr/1800 AA Au and 450 AA Mo/1800 AA Au thin films deposited on optically polished, z-plate single crystal quartz surfaces is discussed. The films were analyzed after deposition and following annealing at 380 degrees C or 450 degrees C for 30 min in either air or vacuum. The resistivity of the Cr/Au film increased by 1090% and 1780% after vacuum annealing at 390 degrees C and 450 degrees C, respectively. These increases were reduced when 1000 AA of Ni or Mo were introduced as barrier layers between the Cr and Au to prevent interdiffusion of the two layers. The resistivity of the Mo/Au films remained unchanged after all annealing exposures. The Cr/Au, Cr/Mo/Au, and Cr/Ni/Au films had adhesion strengths of 41 to 70 MPa in both the as-deposited and annealed conditions. The adhesive strength of the Mo/Au metallization was 23 to 31 MPa except after the 450 degrees C air anneal, where the value dropped to zero. The residual stress of the as-deposited Cr/Au films was 170 MPa (tensile) but became compressive at -120 to -250 MPa after annealing. The Mo/Au metallization was deposited with a zero stress value that also became compressive at -140 to -180 MPa. >

Polymer-cement composites are known repair materials. The aim of this work is to investigate the influence of various amount of dispersion of carboxylated styrene-butadience copolymer on the selected mechanical properties of polymer-cement concrete (PCC) and on its adhesion to ordinary concrete. The compressive, flexural and tensile strengths as well as frost resistance and fracture resistance of the composites are tested. Adhesion strength of PCC to ordinary concrete, as one of most important performance of good repair material is evaluated and analyzed using three test methods. The results obtained in standard pull-off test are compared with the two other tests. The first one, which is an adaptation of WST (wedge splitting test) characterizes crack propagation in the plane of bond created during repair. In the second test the resistance to shear is a measure of adhesion strength.

A description is given of a method of determining the adhesion strength in a polymer—solid system at constant values of the internal stresses and the internal and external stress concentration. Measurements of the adhesion strength have been made under these conditions in the polymer—steel system for different kinds of resins (epoxy, phenol—formaldehyde, polyester, polyimide, polybenzimidazole, silicone, etc.). Values of the components of the adhesion strength — internal stresses and adhesion — are determined for the epoxy—steel and polymethylphenylsiloxane—steel systems.