EFFECT OF SEVERE PLASTIC DEFORMATION ON STRUCTURE AND PROPERTIES OF AUSTENITIC AISI 316 GRADE STEEL
The article presents results of investigation of structure and properties of austenitic steel grade AISI 316 after application of Equal Channel Angular Pressing (ECAP) at the temperature of approx. 290C. The ECAP method leads to significant improvement of strength of investigated material. Investigation of structure was made by combination of TEM and FEG SEM together with EBSD. Statistic evaluation of angular disorientation and of size of grains/sub-grains was also made with use of electron diffraction (EBSD) in combination with scanning electron microscope FEG SEM Philips. It was proven that the ECAP method enables obtaining of ultra fine-grained austenitic structure. It was established with use of the EBSD technique that after 8 passes through the ECAP die the sub-grains with misorientation angles smaller than 10 formed less than 20% of the final structure. Average size of austenitic grains with high-angle boundaries after 8 passes was approx. 0.1m.
Characterization of the structure of FeAl alloy after hot deformation
Purpose: Purpose of this paper was the study of the microstructure of Fe-38Al alloy after hot deformation with the dislocation structure description. Design/methodology/approach: Methodology of the microstructures research included LM (light microscopy) and TEM (transmission electron microscopy) techniques which has characterized the dislocation structure in these materials. The Fe-38Al alloy has been deformed by torsion plastometer within the range of temperatures from 850°C to 1250°C. All samples has been deformed to rupture. Findings: The findings of this study is that the deformation in this alloy is controlled by dislocation motion. The observed dislocations are predominantly of and . At a deformation temperature of 1100°C TEM observations have shown dislocation loops and helices. In this alloy was observed dynamic recrystalization process during the hot deformation. Practical implications: Practical implications of this research is that this alloy may by deformed in long range of strain in temperatures at 800°C to 1000°C Occure 1100°C the plasticity is limited by order - disorder transformation. This transformation could be responsible for dislocations structure behavior what was found. Originality/value: Value of this paper was important in providing a better understanding of technological plasticity of FeAl alloys. The dislocation and reactions between the defects of the structure play a dominant role and are responsible for the variation of technological plasticity.
Reconceptualizing Vagrancy and Reconstructing the Vagrant: A Socio-Legal Analysis of Criminal Law Reform in Canada, 1953-1972
This article explores significant reforms to the vagrancy section of the Criminal Code during the mid-to-late twentieth century. By locating the reforms within their unique social, political, and economic climates, I examine how they reconceptualized the offence of vagrancy and concomitantly reconstructed the vagrant as a social problem. The reforms played a seminal role in reducing the number of vagrancy offences, eventually leading to the demise of vagrancy in the criminal law. Yet, while the "vagrant" ceased to exist in the law, the law still continues to preserve vestiges of the vagrant in a highly gendered manner.