Damage zone development and failure sequence in glass fibre mat-reinforced polypropylene under static loading conditions
The size of the damage zone in glass mat-reinforced PP (GMT—PP) can well be estimated by locating the acoustic emission (AE) events monitored during loading. It was shown that the extension of this zone can be adequately approximated by a circle of about 30-mm diameter, the half of which penetrates into the free ligament of the specimen.
Due to this very large damage zone, reliable mechanical properties can be determined only by using specimens with proper dimensions.
Analogies between the course of AE events as a function of the loading in different GMTs were attributed to an analogous mesh size of the reinforcing mat which characterizes its deformability. This seems to control the stress transfer and stress redistribution in the crack tip and controls the size of the damage zone.
KeywordsPolypropylene Loading Condition Acoustic Emission Mesh Size Glass Fibre
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