Affiliation:
1. Department of Mechanical Engineering, AUT University, Auckland 1020, New Zealand
Abstract
Multipass friction stir processing (FSP) of cast Al -7 Si -0.3 Mg alloy was conducted and FS microstructures were related to the fracture paths and tensile properties. It has been found that high rotation speed (ω) FS caused alignments of Si particles, providing easy paths for fracturing during loading and resulting in low elongation and lower UTS values of the processed alloy. The material flow mechanism during FS leading to the alignments is suggested. This suggested mechanism has been verified after conducting FS experiments using a lower ω value which eliminated Si particle alignments and thus allowed high elongation and UTS values to be attained.
Publisher
World Scientific Pub Co Pte Lt