Fracture initiation in FCC and BCC metals during tribology
The current understanding of wear of metals shows that the crack initiation mechanism is related to surface fatigue which occurs as the metal experiences repeated loading cycles. However, it was revealed that cracks can form even in single stroke tracks and that the crystal orientation determines the crack patterns.
Our aim is to better understand the crack initiation mechanism during single stroke experiments and the effect of grain orientation on crack formation in FCC and BCC metals. The microscale experiments are carried out with a tribolmeter and the crack formation is studied using scanning electron microscopy (SEM) with Electron Backscatter Diffraction (EBSD) analysis, focused-ion beam (FIB) cross-sectioning and transmission electron microscopy (TEM).
The fundamental understanding of crack initiation in microscale will improve the macroscale understanding of wear and friction in engineering metals. With that knowledge we can reduce more effectively wear and friction and further the reduction of replacement costs, noise and energy consumption.
Microscale wear track in a steel. Secondary electron image and crystal orientation in the surrounding of the wear track.
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