The reported event could be confirmed: the returned plates show fractures.Three plates of the set under complaint were returned in order to determine the root cause of the failure.The samples were examined regarding its dimensions, chemical composition (edx analysis) and by light and scanning electron microscopy.The (measurable) dimensions are in accordance with the specification.The chemical composition of all three plates conform to the specification titanium grade 3.The macroscopic appearances of all three plates point to exceeding the material strength.That is confirmed by the deterioration of the anodization layer, the changes of the surface¿s structure, and the secondary cracks in the area of the breakages.The fracture surfaces were partially and / or totally leveled due to friction with the counterpart.The undestroyed fracture surfaces (rest) show the appearance of a low cycle fatigue rupture.The fractographic investigations with sem show a structure of a low cycle fatigue rupture with secondary cracks and in addition, swinging lines of a fatigue breakages are visible.The further provided information did not show any deviation from the user¿s instructions.All relevant quality documents (manufacturing and inspection documents) have been reviewed.The device history records for catalog # 78-92008 and lot code # 2008141014 indicate (b)(4) was manufactured, accepted into final stock on 2020-aug-28.No issues could be found in the manufacturing or inspection documents.Based on the investigation and the corresponding statistical evaluation there is no indication for an incorrectly working product or any systematic design, material or manufacturing related issue.Therefore, no corrective and / or preventive actions are deemed necessary at this time.
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