ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Mechanical Milling (MM) is a Severe Plastic Deformation - Powder Metallurgy(SPD-PM) process which enables to produce a nano grain structure. A BCC layer with a nano grainstructure appeared in the vicinity of the MM powder surface. Conventional cold work at roomtemperature never induces a strain-induced-martensitic-transformation in the SUS310S stainlesssteel. Therefore, a BCC layer formation from austenitic matrix is a specific phase transformation,and is attributed to the rise of the grain boundary energy by the nano grain formation. The hardnessof this surface layer has approximately 540Hv, while that of the inner area has about 290Hv. As theMM powder anneals at 333K for 300s, the hardness of surface and inner area decreases toapproximately 470Hv and 280Hv, respectively. Result of such a large hardness decrease in thesurface of MM powder after annealing at near the room temperature indicates an existence of ahuge number of defects, such as vacancy and interstitial atom, by the SPD-PM Process
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/17/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.558-559.1305.pdf
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