A Study on the Adhesion of Metals (Report 4)

Abstract

As reported in the previous papers, the effect of electric field acting during bonding process on adhesive strength was examined and it became evident that in the case of epoxy adhesive and polyvinyl chloride (PVC), the adhesive strength was influenced by the D.C. electric field and referring to polyethylene (PE), the influence of the electric field on adhesive strength was not observed.
In this paper, it is intended to investigate the phenomena above mentioned from the viewpoint of dielectric relaxation.
The results are summarized as follows:
(1) As to epoxy adhesive and PVC, the absorption currents were observed and as to PE, they were scarcely observed. The observed absorption currents are assumed to be due to the orientation of dipoles and accumlation of ions near metal surfaces.
(2) The changing rate of charge that is calculated from absorption current as a function of time and that of adhesive strength resemble each other
(3) It is assumed that the influence of electric field on adhesive strength is caused by the accumulation of ions ncar metal surfaces or the orientation of dipoles.