Analyse par observation microscopique des défauts des pièces moulées en polymères cristallins

Crystalline materials failure analysis using microscopic techniques

Conseiller technique. Division Plastiques techniques Du Pont de Nemours

Abstract

The study of the structure of crystalline material is a useful tool to reduce rejects, optimize moulding conditions and improve the quality of the moulded components. However, once a fairly good thin section has been prepared, it is not always easy to interpret what is seen in the structure and to pinpoint the reason of failure. Experience is needed to be able to identify what has gone wrong in the production, tooling or even designing.

A thin section of 5-20 µm prepared from a moulded component does not permit a statement about the quality of a whole series. However, if parts fail in testing or in use, an analysis of the structure of a thin section from such a part in comparison to a good one will be of great help in recognizing the possible cause of failure and hence preventing them in the future.