Analysis of an Axle Failure under Torsional Load

Abstract

Premature fracture of an axle under torsional load occurred after a tracked military tank had experienced field testing for only 80 kilometers. Visual metallographic examinations were performed with optical microscope (OM) and scanning electron microscope (SEM). The investigation demonstrates that the premature fracture is caused by metallurgical problems inside the axle where the primary and secondary cracks originate, propagate, and eventually result in final catastrophic rupture through torsional fatigue. The failure mechanism is summarized and improvement of the fatigue lifetime for the axle is recommended.

Failure analysis of an axle shaft in an airport ground support vehicle

“…Therefore, there must be discontinuities that form stress concentrations and reduce torsional strength in the fracture zone of the middle cylindrical region of the axle shaft, such as cracks due to impact, high surface roughness, inclusions or brittleness from improper heat treatment or chemical composition. [5][6][7][11][12][13][14][15][16][17][18] Thus, the axle shaft will fracture as in this case.…”

“…Examples for these discontinuities are cracks due to impact, high surface roughness, inclusions or brittleness from improper heat treatment or chemical composition. [5][6][7][11][12][13][14][15][16][17][18] It is unacceptable for a part to fail and when this happens failure analysis is required to make the parts more durable.…”