New Pictures

In order for fatigue fracturing to take place, there has to be cyclical torsional loading of varying degrees, together with a manufacturing defect.

The rotation of the shaft in forward motion is anti -clockwise, this shows the typical sign of FATIGUE failure. The step at twenty past indicates that the shaft exited with the bearing intact until the final moment of failure. Picture © David Bailey. 2002.

	This picture shows the initial fracture at a depth of 10mm within the splines of the wheel hub, the corroded area is further undercut as are areas above this initial fracture face. Picture © David Bailey. 2002.

	This Picture shows the fatigue crack propagation from stress concentration points on the hub splines, along with striation of the fracture face. Picture © David Bailey. 2002.

	This picture shows the whole of the fatigue fracture area, with only a small part of the shaft remaining intact before final catastrophic failure. Picture © David Bailey. 2002.
	This picture shows the exit marks of the shaft, note the small mark far left and the apparent short distance the shaft has traveled compared to the apparent longer distance right of centre, this is because at this point the shaft had been fatigued through and the exit marks are caused by a secondary failure, leaving a "free" slice of shaft which was lost in the accident. Picture © David Bailey. 2002.
	This picture shows in detail the undercut area, which is highly corroded indicating this failure had taken place over a consirable period of time. Picture © David Bailey. 2002.
	This picture shows clearly the clean exit the shaft made leaving the small step undamaged, it also shows fatigue failure can "cut" around the hub splines without damage to the hub. Picture © David Bailey. 2002.
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