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A stress durability test method that incorporates exposure to a corrosive environment has been used to evaluate the performance of adhesively bonded steel joints. For the systems examined, corrosion exposure is more damaging than exposure to humidity alone. The combination of load and corrosion exposure is substantially more severe than either alone. A method for analysis of the data and comparison of the test results for the evaluation of adhesive bond durability is proposed. The dependence of lifetime on load is defined as , where f is the ratio of applied load to initial, unexposed failure load. The exponent n provides a measure of the degree of acceleration of the interfacial degradation processes by load.

An overview of the principal factors involved in the initiation and propagation of the corrosion of painted steel is presented. One of the major protective functions of the paint system is to act as a barrier to electrolyte; corrosion begins at sites where penetration of electrolyte has occurred. Loss of paint adhesion, caused in most cases by cathodically produced alkali, results in the spread of corrosion. Improved corrosion protection can be obtained by use of alkali-resistant paint binder resins. Corrosion inhibitive pigments can improve performance by slowing the overall corrosion rate; conversion coatings can slow the lateral spread of alkali attack.