0000000000459326
AUTHOR
Mirosław Wróbel
showing 3 related works from this author
Use of positron annihilation measurements to detect the defect beneath worn surface of stainless steel 1.4301 (EN) under dry sliding condition
2012
Abstract Positron measurements were performed for detection of the subsurface zone in the stainless steel 1.4301 (EN) exposed to dry sliding. They revealed the defect profile induced by dry sliding which is extended inward the worn surface from 85 μm to 400 μm depending on the applied load during the tribo-test. This result was obtained using the positron techniques, while the microhardness profile exhibited shorter range of the microhardness depth profile, i.e., from 70 μm to 150 μm. However, at the depth of about 5 μm from the worn surface the sudden increase in the microhardness was observed. The complementary measurements of X-ray diffraction and SEM micrographs of the worn surface were…
Positron Studies of Subsurface Zone in Titanium Created in Sliding Wear
2014
Positron annihilation studies of the subsurface zone constituted during dry sliding in pure titanium are reported. A new type of defect depth profile in this zone, which is not an exponential decay usually reported for other metals and alloys, is observed. Two layers in the subsurface zone are present in this metal. In the layer adjacent to the worn surface, the characteristic plateau of the mean positron lifetime that extends to a depth of 60–70 μm was observed. Small vacancy clusters and dislocations were recognized in this layer. At deeper zone, the mean positron lifetime decreased exponentially in the manner typical for the other metals. In this zone, vacancy clusters increase in size a…
Positron Annihilation Study of Defects Induced by Various Cutting Methods in Stainless Steel Grade 304
2011
We report in this article the comparison of the subsurface zones (SZs) in austenitic stainless steel 304 samples created by three cutting techniques, i.e., the laser cutting (LC), abrasive water jet (AWJ), and traditional milling cutting (MC). The crystal lattice defects distribution in this zone were investigated using the positron annihilation method. It was shown that the MC creates the great number mainly edge dislocations decorated by vacancies. Their concentration decreases with the increase of the depth from the cut surface. The total depth of the SZ is extended up to 150 μm from the cut surface. Similar dependency was observed for the AWJ machining but the total depth is much lower,…