Application of Failure Analysis Methodology

The goal of failure analysis is to characterize the fluoroplastic at the point of defect to compare with material characteristics in unaffected areas. The latter is referred to as control, which can also include the basic properties of the fluoropolymers where the effects of fabrication and service have been 

A fundamental requirement for successful use of this methodology to determine the root cause of failures is complete familiarity with material properties, part fabrication, and process fluids, conditions, and excursions. A majority of the failures involve one or more variables related to the process 

The pure scientific approach in failure analysis is to proceed without any presupposition of a possible cause. Accordingly, the analyst would make various measurements to collect sufficient data to analyze and then develop a cause for the failure. This approach is preferable whenever possible. In the majority of practical situations, time and resources do not allow the analyst to follow the pure scientific approach. The analyst should then develop a list of potential causes that could result in the observed defect. The most likely cause(s) should then be selected based on all the available information. 

Material Composition 1. Analysis of composition of the polymer and additives 2. Degree of crystalhnity, molecular weight, molecular weight distribution, and degree of fusion 3. Identification of contaminants at the failure point 4. Surface analysis 

Physical Properties 1. Density/specific gravity 2. Melting point 3. Glass transition temperature 4. Melt viscosity/melt flowrate (MFR) 

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