Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7966299 | Journal of Nuclear Materials | 2015 | 7 Pages |
Abstract
The effect of Si in the range of 0.05-0.77Â wt.% on the microstructure, tensile properties and impact toughness of reduced activation ferritic/martensitic (RAFM) steels has been investigated. An increase in Si content affected the prior austenite grain size resulting in an increase in the tensile strength at room temperature. The tensile strength of steels tested above 773Â K did not change significantly with the addition of Si, which was due to the diminished carbide hardening effect and boundary strengthening effect. Detailed fractographic analysis revealed that tear fractures occurred in the samples tensile tested at room temperature, while cup and cone fractures were found in samples tensile tested at temperatures above 773Â K, which were induced by the easing of dislocation pile-ups. The ductile-to-brittle transition temperature (DBTT) decreased when the Si content increased to 0.22Â wt.%. However, the DBTT increased when the Si content reached 0.77Â wt.% and this was due to the precipitation of Laves phase. The RAFM steel with approximately 0.22Â wt.% Si content was found to possess an optimized combination of microstructure, tensile properties and impact toughness.
Related Topics
Physical Sciences and Engineering
Energy
Nuclear Energy and Engineering
Authors
Shenghu Chen, Lijian Rong,