Boundary Layers and Physico-Mechanical Properties of Adhesive Joints: Part I Experimental Background

Abstract

Various hypotheses of boundary layer formation in adhesive joints are reviewed. The features of boundary layers in joints obtained by means of thermoplastic and thermoreactive adhesives are studied, and substrate boundary layers are estimated. The examples of influence of density, elasticity modulus and other properties of boundary layers upon adhesive joint properties are presented.

An original method to design adhesive joints is proposed, based on the concept of special boundary layer properties. By means of this method the problem of mechanical performance of an adhesive lap shear joint is solved. The effects of various parameters of the theoretical model are compared with the experimental data.

Key Words:

• Adhesive joints
• boundary layers
• adhesives
• physical-mechanical properties
• joint design
• stresses
• deformations
• strength.