Erosion-corrosion of RAFM JLF-1 steel in Lithium flow induced by impeller
The purpose of the present study is to investigate erosion-corrosion characteristics of reduced activation ferritic martensitic steel, JLF-1 (Fe-9Cr-2W) in flowing Li. The erosion-corrosion characteristics were investigated by means of corrosion tests with rectangular plate type specimen of JLF-1 in Li stirring pot, where the Li flow was induced by impeller in the pot. The test temperature was 500 C and 600 C, and there was no temperature difference in the Li stirring pot. The erosion-corrosion characteristics were evaluated by the weight loss measurement of the specimens and metallurgical analysis for the corroded surface. The results were compared with those obtained from the tests at static condition to feature the effect of Li flow on the corrosion. The weight loss of the specimens tested in Li flow was larger than that tested in the static tests. The corroded surface showed the local corrosion along lath boundary and grain boundary of JLF-1 as the same as that after the test at static condition. There were defects which were not observed in the specimen tested at the static condition. The defects were the trace of the erosion-corrosion. The corrosion attack to the boundaries made weak bonding between the subgrains, and the subgrains were peeled from the surface by the Li flow.
Effect of chemical potential of carbon on phase transformation and corrosion of JLF-1 steel in a static lithium
Abstract The corrosion and the phase transformation of RAFM (Reduced Activation Ferritic/Martensitic) steel, JLF-1(Fe–9Cr–2W–0.1C), in static lithium (Li) were investigated. The specimens were exposed to static Li at 600 °C for 250 h. The carbon potential in Li was controlled by the carbide formation on inner surface of the crucible, which was made of Mo and Nb. These materials were expected to form stable carbide, and worked as carbon trap in Li, which resulted in the decrease in the carbon potential of Li. The effect of low carbon potential on the corrosion and the phase transformation was characterized by comparison with the test performed in the crucible made of Fe–9Cr and SUS316L (18Cr–12Ni), which has no effect as carbon traps. The low carbon potential caused by Nb and Mo caused the dissolution of carbon from the surface of JLF-1 specimen to Li. The depth of the phase transformation observed after the test in Nb crucible was deeper than that tested in Mo crucible. This was because the stability of the Nb carbide was larger than that of Mo carbide causing larger driving force for the dissolution of carbides from the surface.
School Principals and Education Law: What do they know, what do they need to know?
Principals now work in complex and challenging environments where uncertainty and change are the hallmarks of their roles and responsibilities. As such, the knowledge and capability demands on principals have expanded, including those related to education law. While these matters attracted some research interest a number of years ago, there has been little recent work in the area of principals and education law. This article reports on an exploratory study into aspects of the legal knowledge held by Tasmanian government school principals, particularly concerning non-sexual physical contact between teachers and students. The research was undertaken using a small-scale, mixed-methods research design, which required principals to respond to various legal scenarios. Three key findings emerged from the study. First, principals used two different levels of working knowledge about education law  one related to legal problems, and the other to legally-related routine activities. Second, on the particular topic of physical contact, some knowledge held by principals was not legally accurate. Third, for major legal issues, participants indicated that they acquired access to information from legal experts. The situation for routine legal matters was less clear, although in-service training and practical experience were identified as potential sources of knowledge. Participants recognised the importance of a sound knowledge of education law, especially for dealing with security and safety issues and preferred to access further information through in-service training. Notably, the findings of the study are broadly consistent with those from earlier Australian and international research, suggesting that much remains to be done in the area of principals’ education law knowledge.