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Analyzing Material Fatigue

Posted by Rob in Failure Analysis on 04. May, 2010 | 0 Comments

A variety of analytical tools and techniques are used to identify fatigue fractures and their root cause. These include macroscopic examination, microstructural analysis, hardness testing, chemical analysis, microprobe chemical analysis and scanning electron microscopy (SEM). There are three stages in the life of a fatigue failure; 1. Initiation, 2. Crack Growth (propagation), and 3. Final [...]

The Service Environment

Posted by Rob in Failure Analysis on 04. May, 2010 | 0 Comments

Once a product leaves the factory you, the manufacturer, have lost control and all bets are off. Abuse and inadequate maintenance are leading sources of failure by fatigue, as well as other failure modes.  Failure of components or assemblies “up stream” from your product may introduce higher loads than the product or component was designed [...]

Fatigue in the “Real World”

Posted by Rob in Failure Analysis on 27. Apr, 2010 | 0 Comments

In the “real world” fatigue usually – that’s usually, not always – initiates at a location that acts as a stress concentration, or focal point, to the stresses imposed on a component. Stress concentrations take a wide variety of forms. They include geometric features (such as holes, slots, corners and radii), rough areas of surface [...]

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Fatigue and its Failure Analysis

Posted by Rob in Failure Analysis on 22. Apr, 2010 | 0 Comments

On May 11th, 1842 the first major railroad disaster in history set off a chain of events which led to the discovery of the phenomenon that we now know as fatigue failure. The Paris – Versailles Express, hurtling down the tracks at the then astounding speed of 50 miles per hour, exploded in flames when [...]