Peel testing of adhesive bonded metal



In this paper the subject of peel is divided into two parts: (1) A mathematical determination of peeling stresses in an adhesive bond due to the applied peeling loads which leads to a mathematical definition of “peel strength.” (2) A review of suitable peel test methods examined in the light of this definition. Employing the assumption that the adhesive bond behaves as an ideal homogeneous elastic material under load, the classical derivation of the deflection of a loaded beam on an elastic foundation is applied to the calculation of peel strength of a metal adhesive. This theory results in a mathematical definition of peel strength and offers a reasonable explanation of the effects of the important variables such as metal and adhesive thickness and strength properties and provides a basis for the comparison and evaluation of the few testing methods presently in use.