Discipline: Technology and Engineering
Subcategory: Civil/Mechanical/Manufacturing Engineering
Gregory Nowlin - Virginia State University
Soft materials such as aluminum are commonly joined using the friction stir welding (FSW) whereas the FSW of hard materials such as steel has not been successful because of excessive tool wear. Several FSW numerical analyses have showed that the localized heating generated in the donor material by the plunge of the FSW tool was used to preheat the workpiece. This preheating of the workpiece significantly reduced axial and contact forces acting on the FSW workpiece because the preheating softens the material. As a result this softening helps to induce the minimum amount of friction on the tool. Since the donor material approach has not been experimentally investigated, however, this study intends to experimentally explore the effectiveness of donor materials on improvement of the FSW tool life in terms of axial force, transverse force, and temperature. In the study, aluminums are used as donor material and copper as workpiece materials. The axial and transverse force data are collected using sensors and a LabView data acquisition system. For temperature measurements, thermocouples are placed 5 mm and 15 mm from the boundary between the donor material and hard material. The experimental results from the FSW workpiece will be compared with the results from the FSW workpiece with donor material. At 5 mm location higher temperature and less forces will be expected in the workpiece without donor than with donor. The microstructural characteristics of the former could be different with that of the latter because they experience different thermal effects. By using this method, we believe that the research results will help to increase in the tool life by reducing the wear during the plunge phase.
Funder Acknowledgement(s): I thank Dr. Jinmyun Jo for advising on this research. Funding was provided by Virginia State University.
Faculty Advisor: Jinmyun Jo, jjo@vsu.edu