Channel formation during friction stir channeling process - A material flow study using X-Ray micro-computed tomography and optical microscopy

In this study, an experiment is performed to investigate material flow and its implication on the channel formation in friction stir channeling process. X-ray Computed Tomography in combination with optical microscopy is used to analyse bulk material flow, geometry and various features of the fabricated channel. In addition, X-ray Micro Computed Tomography analysis of friction stir channeling sample with broken pin embedded in it is used to further reinforce the information about material flow and deposition during the process. The results show that there are five distinct material regions responsible for the formation of four sides of the channel. These are pin influenced material region (advancing side channel wall, retreating side channel wall, channel roof, and channel bottom) and shoulder influenced material region (top portion of channel roof).