Failure, Defect, and Contaminant Analysis

James D. Rancourt, Jennifer Brooks, Sue Mecham, Alan Sentman, Brian Starr and Jason Todd 

Contamination can be present not only as a surface deposit or a surface feature but can also be located within the bulk of a manufactured part. The selection of an appropriate series of analytical techniques, applied to failure, defect, and contamination analysis projects, is influenced by the location of the contamination or defect and the optical properties of the manufactured component. Microscopic analysis of opaque parts is limited to surface analysis 

ISSN 0166-526X, DOI 10.1016/S0166-526X(08)00415-7 All rights reserved. 

The selection of an analytical technique that allows for the chemical characterization of a contamination or defect that is a potential contributor to a failure is influenced by some major factors. For example, some techniques are able to characterize inorganic materials, while other techniques are better suited for organic materials. Further, some analytical techniques require that the specimen be volatile, other techniques require that the sample be soluble, and still other techniques require that the sample be in a solid form. 

A comprehensive review of compositional and failure analysis of polymers, which includes many further examples of analysis of contaminants, inclusions, chemical attack, degradation, etc., was published in 2000 [2], It includes details on methodologies, sampling, and sample preparation, and microscopy, infrared spectroscopy, and thermal analysis techniques. 

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This topic has been mentioned in Section V, Failure, Defect and Contaminant Analysis, in Chapter 15, where a number of typical practical problem invetsigations were presented. Obviously the potential list of examples exhibiting different characteristics and requiring a different type of analysis is lengthy. When the sample is heterogeneous, e.g., a polymer blend or a composite, the study of the surface of a failed piece of material may reveal whether the problem is the interface of the components or that failure occurred within one of these. In particular in the case of crazing or necking orientation may have been induced, the way this can be analysed is discussed in Chapter 8. 

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