Failure Analysis

A Study of Why the Component does not full fill its Purpose

There are two perspectives on this subject. The first is a large-scale study and the second is the micro study of the component or equipment. They are as follows:

Forensic engineering study (large-scale failure analysis) relates to the big picture in evaluating the reasons for the failure and should include contributing factors and more than just a root cause. The forensic work may use Finite Element Analysis (FEA), MORT (management oversight risk tree) or other investigation tools like Change Analysis, reconstruction and others to understand the forensic engineering aspects. In addition, forensic engineering may employ metallurgical work when necessary.

Failure analysis at the micro level is a narrow study of how the component failed. In our discussion we are interested in using metallurgy to study and understand the failure as this relates to the pieces of metal that failed. The conclusions from a metallurgical study may possibly provide an accounting, providing enough information is available, of what the metal experienced through the failure from beginning to end.

Together, metallurgical failure analysis and forensic engineering study can provide a more complete picture of the failure.

A metallurgical failure analysis may be all that is needed to solve the failure of why the component failed.  The metallurgical failure analysis will include some or all of the following to full fill this aspect of failure analysis:

• Microscopic examination of the grain structure (microstructure)
• Hardness Test
• Tensile Testing with yield and elongation
• Chemical Analysis
• Impact or Toughness Evaluation
• Fatigue Studies
• Fractography (the study of the fractured surface)
• Corrosion Evaluation

As a finally note...a metallurgical failure analysis may include field work but not all tests can be completed in the field. We hope that this overview helps you understand the perspective of failure analysis better.

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