Tjuk Oerbandono, Victor Yuardi Risonarta
This study investigated the friction stir welding of aluminum alloys, which exhibit high thermal conductivity AA6063. The main object in this study is the welded joint of AA6063. The scientific discussion is based on the lack of transferability of friction stir welding parameters developed for the aluminum alloys with low and medium thermal conductivities to AA6063, thereby resulting in inferior joint quality. For AA6063, rapid heat transfer influences joint quality, mechanical properties and grain size. The process parameters in this study were spindle speeds and pin depths, which were varied in the range of 1,450 to 1,850 rpm and 2.5 to 4.0 mm, respectively. For most cases, the optimum spindle speed and pin depth were 1650 rpm and 3.5 mm. The best values of yield strength, ultimate tensile strength, fracture strength and bending strength were 117.45 MPa, 138.64 MPa, 111.35 MPa and 264.62 MPa, respectively. A novel quantitative analysis of grain size showed that varied grain sizes were due to diverse spindle speeds and pin depths. A novel mathematical model correlating the tensile and the bending strength was developed in this study. The developed model facilitates the estimation of one mechanical property based on the other value, thereby reducing the effort and cost for destructive tests. Moreover, this approach can be applied for materials characterization, quality control and design of components experiencing both tensile and bending strengths, e.g. shaft and cantilever. The features in this study lies in the appropriate spindle speeds and pin depths for the friction stir welding of aluminum alloys with high thermal conductivities. Additionally, the features are new values for yield strength, fracture strength, bending strength and quantitative values of grain size as well as a new correlation between yield strength, UTS and bending strength. The quantitative analysis of grain size, which has been scarcely discussed in any previous literature, can serve as reference values for future studies. © 2026, Scientific Route. All rights reserved.
Department of Mechanical Engineering, Brawijaya University, 167 MT Haryono, Malang, 65145, Indonesia
