After performing an alternating load test for several monobloc tubular shafts (so called MTS) a fractographical evaluation with subsequent metallographic examination as well as a review of the heat treatment according to drawing requirements were carried out on a test component which had reached the lowest number of cycles.An example is used to present a typical examination procedure in a quality laboratory which helps to ensure high product quality in a automotive supplier company and is supposed to highlight the close connection to and support for elaborate bench tests through the instrument of metallography. Besides the fractographical determination of the damage origin, an evaluation of heat treatment and microstructural development of the components is prerequisite for assessing the examination results.

No abstract