Failure Analysis Utilizing Magnetic Inspection Techniques for a Hex Drive Shaft

A failure analysis was conducted on a hex drive shaft that was being developed for the vertical drilling market. During the failure investigation, evidence of decarburization was observed. Analysis was conducted via fractography, optical emission spectroscopy, hardness, tensile testing, magnetic particle inspection, and magnetic rubber replication. The failure mode and the potential root cause of the failure will be discussed. Recommendations are provided to prevent recurrence.