Adhesion of polyethylene to high temperature aluminum oxide films formed in the air

Studies on aluminum surface and its adhesive strength (1st report)

Abstract

Effects of the surface films of aluminum on adhesion of polyethylene were investigated by the relationship between peeling strength and thickness of the oxide films or by observation of the surfaces under a scanning electron microscope.
The following conclusions were drawn from the experiments:
(1) The increase in thickness of the films greatly depended upon the heating temperature, and the adhesive strength decreased with the increase of the thickness. In other words, adhesive failure between aluminum surface and polyethylene or cohesion failure in the polyethylene film occurred on electro-polished aluminum specimens; while, cohesion failure in the oxide film was observed on aluminum oxidized in the air at high temperatures.
(2) Adhesive strengths of anodic oxide films and some converted films such as boehmite film and chromate film were greater than those formed in the air.
Therefore, cohesion failure in the polyethylene film was observed in these aluminum specimens.