Successive Grinding and Polishing Effect on the Retained Austenite in the Surface of 42CrMo4 Steel

Low-alloy 42CrMo4 steels were studied by 57Fe Mössbauer spectroscopy (MS), X-ray diffractometry (XRD), and Energy Dispersive Spectroscopy (EDS) measurements. The investigations performed on metallographic samples, which subjected to a series of successive grinding polishing with progressively finer grit. Conversion (CXMS) was used determine the occurrence austenite in steel samples. It is unique method detecting content very sensitively. Six samples different surface preparation investigated, starting 4.8% an as-cut sample, large decrease retained 2.6% observed after first hardened cut sample. Additionally, unexpectedly 2.3% found due final polishing. A second time applied all resulted identical determined CXMS approx. 5%, proved applicability method. Generally, result calls attention importance metallurgical where results can vary significantly level processing.