Effect of Straining Rate on the Mechanical Behavior of Adhesive Bonds Under Shear Deformation
H Chai, Martin Chiang, Carl R. Schultesiz
The mechanical behavior of adhesive bonds is of interest in a variety of technological applications, including traditional adhesive bonds, laminated structures and composite materials. In this work, the stress strain response of adhesive bonds undergoing simple shear was determined as a function of local shear strain rate. The test specimens were based on the napkin ring configuration. The specimens are made of two cylindrical rods which edges are machined to a ring shape. Torsion tests were carried out with the aid of a servo hydraulic testing machine under a controlled shear strain. The latter was measured with the aid of a specially devised apparatus that utilizes a standard extensometer to convert the relative shear displacement across the bond to shear strain. Utilizing this output in a closed-loop routine, the actual strain rate in the adhesive could be controlled. Tests were carried out at constant rates of shear strain (i.e. from nearly quasi-static conditions up to 0.5/sec ) on a toughened epoxy adhesive with thicknesses in the range 50 mm - 80 mm. Over the range of parameters studied, the yield and failure stresses of the adhesive changed relatively little. However, the ultimate shear strain of the adhesive was greatly affected by the parameters above, being monotonically decreasing with increasing shear strain rate. Finally, it is believed that the present testing approach controlling the local strain rate in the adhesive eliminates many of the complexities marring more traditional tests which are performed by controlling the global strain rate conditions.
, Chiang, M.
and Schultesiz, C.
Effect of Straining Rate on the Mechanical Behavior of Adhesive Bonds Under Shear Deformation, Adhesion Society, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=851839
(Accessed June 1, 2023)