Failure or Competitive Analysis

A major objective of microstructural analyses on multiphase and other polymers is failure analysis, that is, determination of the mode or cause of failure, especially of a product in use in the marketplace. Failure analysis generally involves characterization of a material that has failed, either in service or in a physical test. Controls are not always available, and timing is often critical. In some cases, the types of analysis required may well be similar to those described above phase contrast light microscopy, PLM, SEM, TEM, and AFM. Other microstructural techniques that are valuable in solving such materials problems are chemical contrast imaging and elemental x-ray mapping. 

X-ray microanalysis and BEI provide information regarding the elemental composition of dispersed phase particles and also of the contaminants responsible for failure. These techniques are useful for the study of multiphase polymers, if one of the phases contains an element not contained by the other. For example. Price et al. [409] used SEM/EDS to study the interface between two polymers, one of which was PVC, to measure the local composition during interdiffusion. Failure of elastomer compounds used in tank track pads, natural rubber, SBR, EPDM, and 50/50 SBR/ BR was studied as a function of elastomer cure and degradation in service [410]. Andrade et al. [411] used BEI of osmium tetroxide stained PS/ PB to provide images that showed the dispersed and stained PB as a result of atomic number 

Another use of microscopy is the study of competitive materials, which is similar to doing failure analysis as the full nature of the material is not known. In this example, the question was to learn the nature of the process used to make a dual ovenable food tray. Transmission electron microscopy cross sections, stained with 

Atomic force microscopy techniques including scanning thermal microscopy have been used in research and failure analysis, as reviewed by Bar and Meyers [170], The insulation material for high tension cables can be composed of 

Incorporation of short or long glass or carbon fibers into many engineering materials improves their strength, stiffness, and heat deflection. The strength and fatigue crack resistance 

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