Journal of Materials Science and Engineering with Advanced TechnologyAuthor's: A. FOROOZMEHR, M. H. ENAYATI and F. KARIMZADEH
Pages: [93] - [105]
Received Date: September 22, 2011, Revised October 19, 2011
Submitted by: Guozheng Kang.
Mechanical milling as a kind of severe plastic deformation process is extensively used for producing nanocrystalline powder. In this research, morphology, microstructure, phase composition, and hardness changes of AISI316L stainless steel chips during ball milling were investigated. During ball milling, austenite in as-received chips, was transformed to martensite with a grain size of about 10nm leading to an increase in hardness value from about 300HV for as-received chips to 800HV for ball milled sample. Heat treatment was done at two different temperatures to investigate the martensite-austenite transition upon annealing. Martensite induced during ball milling was transformed to austenite by annealing at 700°C partially and completely at 900°C. In the case of annealing at 900°C, the austenite grain size increased with cooling rate.
austenite martensite transformation.
