Characterisation and Performance Evaluation of Calcium Treatment in Automotive Steels

Advanced High Strength Steels (AHSS) are seeing a dramatic usage increase in order to achieve the reduction in weight required for automotive vehicles to adhere to new legislation on emissions. This has resulted in the increase of use of Calcium (Ca), as a means of both oxide and sulphide-based inclusion control. However, this process is not well understood, with no definitive answer on the level of Ca required to obtain adequate modification of the inclusion population within the steel. As a result, this thesis studied the level of Ca addition applied to the dual-phase steel grade, FB590, by analysing its Calcium Sulphur Ratio (Ca:S). This allowed for the level of modification needed to obtain the required mechanical properties to be studied. It was discovered that even at the low Ca:S of 0.23, sufficient modification of the inclusions was achieved to obtain these properties. Samples across the entire Ca:S range obtained a substantial increase in the number of ‘globular’ inclusions when compared to non-Calcium treated samples. The second aspect of this project was to automate the process of analysing the inclusion populations within the steel. Typically, this is done manually and is very time consuming. The resulting automated process analysed a stitched image of the entire sample surface (200mm2) taken at a typical magnification (100x) and was conducted as closely as possible to the BS EN 10247 and ASTM E45 standards. A custom macro was written that allowed this image to be broken up into fields, each of which were analysed individually, for both inclusion population and size. This method proved significantly less time consuming while generating a vast amount of data that would be unavailable utilising standard analysis techniques. The key problem with the technique, however, is that it did not include the ‘grouped’ inclusions stated in the standards. Nevertheless, EDS analysis proved that a significant proportion of these inclusions were in fact distinct globular inclusions and therefore not the inclusions separated by the polishing process that the standard assumes. A suggestion has been made to conduct all future inclusion analysis on FB590 at 500x magnification so as to reduce the negative effects of pixel size. A series of different regions would then be analysed to better ensure the accuracy of the results

The use of motion pictures and filmstrips in teaching industrial arts in the seventh and eighth grades

Thesis (Ed.M.)--Boston University, 1948. This item was digitized by the Internet Archive

Technical Institute, Kevin Street : Prospectus, 1939- 40

Courses and timetables for Dublin Institute of Technology, Kevin Street

Technical Institute, Kevin Street: Prospectus 1938-39

Courses and timetables for Dublin Institute of Technology, Kevin Street

Proceedings of the 40th Aerospace Mechanisms Symposium

The Aerospace Mechanisms Symposium (AMS) provides a unique forum for those active in the design, production and use of aerospace mechanisms. A major focus is the reporting of problems and solutions associated with the development and flight certification of new mechanisms. Organized by the Mechanisms Education Association, responsibility for hosting the AMS is shared by the National Aeronautics and Space Administration and Lockheed Martin Space Systems Company (LMSSC). Now in its 40th symposium, the AMS continues to be well attended, attracting participants from both the U.S. and abroad. The 40th AMS, hosted by the Kennedy Space Center (KSC) in Cocoa Beach, Florida, was held May 12, 13 and 14, 2010. During these three days, 38 papers were presented. Topics included gimbals and positioning mechanisms, CubeSats, actuators, Mars rovers, and Space Station mechanisms. Hardware displays during the supplier exhibit gave attendees an opportunity to meet with developers of current and future mechanism components. The use of trade names of manufacturers in this publication does not constitute an official endorsement of such products or manufacturers, either expressed or implied, by the National Aeronautics and Space Administratio

Bulloch Times (Statesboro News-Statesboro Eagle)

https://digitalcommons.georgiasouthern.edu/bulloch-news-issues/3365/thumbnail.jp