Papers by Author: Yoji Marutani

Abstract: Friction Stir Welding (FSW) for aviation and automobile applications has been investigated at Osaka East Urban Area Industry-Government-Academia Collaboration Project on FSW sponsored by a Japanese ministry of education, culture, sports, science and technology, 2004-2007. The objective of this project is the three dimensional (3D) FSW of light metallic materials. The project consists of two simultaneous investigations. One is the approach from material side. The establishment of optimum FSW conditions and the construction of the FSW equation between weld condition and formed microstructure. The other is the approach from 3D software. The construction of optimum algorism for 3D FSW is the main theme. The construction of 3D FSW expert system for aluminum alloys, magnesium alloys and titanium alloys is the goal of us in combination of the results developed by the two research group.

Abstract: The influence of roll angle of the FSW tool rotation axis on tensile properties of joints was examined to clarify the allowance of deviation from proper tool posture for three-dimensional friction stir welding. A5083-O plates of 3 mm in thickness were butt welded by three-dimensional controlled FSW machine. Transversal inclination of the tool (roll angle of the tool) was continuously changed from 0 degrees to 10 degrees for both sides. Butt joints ruptured at base metal within the range of roll angle of the tool plus/minus 2 degrees, and ruptured at the thin part made by inclined tool shoulder entering in the range by plus/minus 7 degrees. Over the range of plus/minus 7 degrees, butt joints ruptured at elongated cavities made by tool inclination at the border of stir zone and base material.

Abstract: A new technology for manufacturing expandable salt patterns to fabricate metallic parts by investment casting is presented and the results of experiments are reported to find out the binder substances suitable for the method. Solid models made by this method are also reported.