23 декабря, 2015 
Pokraskin Joint design is discussed in more detail in Chapter 5 and can have an important influence on the durability of the joint so a few general points relating to durability are discussed here.
Adhesive bond lines will always be susceptible to environmental attack and a thick bond line (>0.2 mm) offers a ready path for access by moisture or other solvents. Thinner bond line gaps therefore are invariably beneficial.
Increasing the bonded area will usually decrease the overall load on the joint and therefore improve the reliability and durability as there is a lower overall stress on the joint. The adhesive will always be stronger in compressive, tensile and shear loads than in peel or cleavage loads and typically the peel load of an adhesive will be less than 5% of the nominal shear strength so ensuring that the bonded joint cannot be subjected to peel or cleavage loads will improve the overall integrity of the joint.
Designing the joint to avoid water or moisture traps wherever practical is logical and sensible as water is usually the enemy of adhesive joints. Many industries now require resistance after prolonged exposure to high temperature and humidity levels (85% RH, 85 °C) and in these circumstances close-tolerance components and using plastics that are not hydroscopic are essential.
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