Evaluation tools adhesion

This value provides an estimate of the toughness of the joint and makes the wedge test a useful tool for the rapid evaluation of adhesive systems. It should not be used as the sole test to determine the suitability of an adhesive or pre-treatment but it will usually reveal poor durability performance in a short time. 

Michaloudaki M, Lehmann E, Kosteas D (2005) Neutron imaging as a tool for the non-destructive evaluation of adhesive joints in aluminium. Int J Adhes Adhes 25 257-267... 

The present work was done with the aim to evaluate the efficiency of the acoustic emission method as a diagnostic tool for analysing a carbon plastic composite and its adhesive joints. The samples of the carbon plastic type UKN-5000 were used in the test. Non-defected samples and samples with artificial defects were tested. 

Surface tensions, interfacial tensions, and contact angles can be used as laboratory tools for the evaluation of the various intermolecular forces that determine cohesion in a single phase or adhesion between two dissimilar materials at an interface. By the use of these tools, considerable information about the magnitude of various intermolecular forces may become available. Basic understanding of means to determine interfacial forces has sprung from the principle of additivity of intermolecular forces at surfaces and interfaces [4, 6]. 

IGC was shown to be a convenient and effective tool for evaluation of acid-base interactions at substrate and adhesive surfaces. 

Mechanical responses of cells to physical or chemical stimuli include cell growth patterns, morphology, adhesion, and motility. Many mammalian cells grown in culture are adherent. For such cells, the adhesive interactions with the physical environment (extracellular matrix or other cells) are a critical determinant of their biochemistry and behavior. Microfluidics has become a useful tool for studying these interactions. Many of these studies are reviewed elsewhere ( Cell Adhesion and Detachment), so the focus here is on assays that evaluate the effects of physical or chemical cues on cell morphology or motility. 

Summary. The Amott, USBM, Spontaneous Imbibition Index, imbibition rate, and capillary pressure are all displacement methods applicable to porous media and the possible evaluation of wettability alteration by surfactants. However, these methods must be complemented by more fundamental studies using contact angles or adhesion studies (Wilhelmy), etc. to meld the understanding of surface interactions with the macroscopic displacement of fluids. To comprehend how a surfactant alters the contact angle on a flat surface provides only part of the information to predict how the surfactant will interact in porous media. To measure only the fluid displacement in porous media provides little information on surface interactions. NMR and/or cryomicroscopy could help span this gap. Cryomicroscopy can directly look at pore surfaces, but for the moment, it is difficult and time consuming to use. Both techniques provide more of a qualitative measure of wettability than quantitative, but they are tools that can complement and help bridge between more fundamental measurements and quantitative displacement methods. 

In order to determine the adhesion quality of a coating, a lattice pattern is cut into it, penetrating to the substrate. A multiple cutting tool consisting of a set of six knives 1 or 2 mm apart is used to yield a uniform pattern. The results are evaluated as shown in Figure 11.7. 

F. Attar, T. Johannesson, Adhesion evaluation of thin ceramic coatings on tool steel using scratch testing techniques. Surf. Coat. Technol. 78 (1-3) (1996) 87. 

T. Sumomogi, K. Kuwahara, H. Fujiyama, Adhesion evaluation of RE sputtered aluminum oxide and titanium carbide thick films grown on carbide tools. Thin Solid Films 79(1981)91. 

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