Damage sudden, catastrophic failure

Thick-layer elastic-bonded joints first yield before they tear when subjected to peeling forces, allowing the load to be distributed over a wider area. Consequently, the stresses within the bonded materials are kept at a relatively low level. The high tear propagation strength of polyurethanes - even after tear initiation - usually prevents sudden and catastrophic failure of the joint. This yielding behaviour means that damaged adhesive joints can often be identified and repaired before... 

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