Nonseacoast Environment

By far, the most detrimental factors influencing adhesives aged in a nonseacoast environment are heat and humidity. The reasons why warm, moist climates degrade many adhesive joints were presented in the last section. Near the seacoast, corrosion due to salt water and salt spray must also be considered when one is designing an adhesive joint. Thermal cycling due to weather, oxygen, ultraviolet radiation, and cold are relatively minor factors with most structural adhesives. 

Extensive information on the outdoor durability of bonded aluminum joints is available in the reviews of Minford.61,62,63 Hartshorn has also provided a catalog of references to outdoor weathering of structural adhesives by adhesive class and exposure conditions.64 

FIGURE 15.20 Effect of outdoor weathering on typical aluminum joints made with four different two-part epoxies cured at room temperature.65 

The following generalizations are of importance in designing a joint for outdoor service  

The most severe locations are those with high humidity and warm temperatures. 

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