Catastrophic Failure of a Brush Cutter Blade

A rented brush cutter, being used to clear plant growth and debris to create a camp site, unexpectedly failed and propelled a fractured blade 30 feet, injuring two bystanders. This presentation discusses the non-destructive and destructive methods used to determine the fatigue failure mode of the blade as well as the influence of maintenance on the catastrophic failure. Installation conditions, fractography and metallography of the blade will be discussed as part of the supporting evidence of the failure mode.