Studying the Hall-Petch effect regarding sub-micrometer steel (0.6% C)

Abstract

This paper study the synthesis and mechanical characterisation of steel (0.6% C) having lower than 1 micron grain size. There was severe plastic deformation in high pressure planetary ball milling and consolidation for obtaining bulk samples at temperatures between 350°C and 500°C. Studying grain size evolution showed that samples without subsequent heat treatment retained their nanocrystalline structure. Grain growth was controlled in heat-treated samples due to many nucleation points and the presence of cementite precipitates. The results obtained regarding hardness and grain size satisfactory agreed with the Hall- Petch ratio. The influence of the synthesis and mechanical characterisation techniques used in this work were compared to results mentioned in several references.

Keywords

• alloy steel
• heat treatment
• Hall- Petch relationship