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An X-cut is made through the film with a carbide tip tool to the substrate. Pressure-sensitive tape is applied over the cut. Tape is smoothed into place using a pencil eraser over the area of the incisions. Tape is removed by pulling it off rapidly back over itself as close to an angle of 180°. Adhesion is assessed on a 0 to 5 scale.
The measurement must be redone with adjacent scale type. Pig sticker used to measure the hardness of pugged clay. Durometer is a dimensionless quantity, and there is no simple relationship between a material's durometer in one scale, and its durometer in any other scale, or by any other hardness test. [1]
A pull-off test, also called stud pull test, is a type of test in which an adhesive connection is made between a stud and a carrier (or object to be tested) by using a glue, possibly an epoxy or polyester resin, that is stronger than the bond that needs to be tested.
Adhesives may be broadly divided in two classes: structural and pressure-sensitive. To form a permanent bond, structural adhesives harden via processes such as evaporation of solvent (for example, white glue), reaction with UV radiation (as in dental adhesives), chemical reaction (such as two part epoxy), or cooling (as in hot melt).
Surface roughness can also affect the adhesive strength. Surfaces with roughness on the scale of 1–2 micrometres can yield better wetting because they have a larger surface area. Thus, more intermolecular interactions at closer distances can arise, yielding stronger attractions and larger adhesive strength.
The success or failure of the bond is based on measuring the applied force, the failure type due to the applied force and the visual appearance of the residual medium used. A development in bond strength testing of adhesively bonded composite structures is laser bond inspection (LBI). LBI provides a relative strength quotient derived from the ...
Adhesive materials fill the voids or pores of the surfaces and hold surfaces together by interlocking. Other interlocking phenomena are observed on different length scales. Sewing is an example of two materials forming a large scale mechanical bond, velcro forms one on a medium scale, and some textile adhesives (glue) form one at a small scale.
Cyanoacrylate glue has a low shearing strength, which has led to its use as a temporary adhesive in cases where the piece needs to be sheared off later. Common examples include mounting a workpiece to a sacrificial glue block on a lathe , and tightening pins and bolts.