In the present study, friction spot welding or refill friction stir spot welding was performed to consolidate dissimilar AA5754 Al and AZ31 Mg alloys. The intermetallic compounds of Al12Mg17 and Al3Mg2 were primarily found in the weld, distributed at the interface between the base materials and in the Al top sheet. The distribution of the intermetallic compounds and the interfacial area between...

Friction stir welding is advance joining process for different similar and dissimilar metals. It is commonly used for joining of Aluminium alloys. In this study an attempt were made to join commercial structuralaluminium with 7039 aluminium alloy. A zig-zag pattern of hardness was found in weld nugget. Microstructural characterization and fractography of joints were examined using optical and s...

this study focused on the optimization of al—mg to cuzn34 friction stir lap welding (fslw) process for optimal combination of rotational and traverse speeds in order to yield favorable fracture load using grey relational analysis (gra). first, the degree of freedom was calculated for the system. then, the experiments based on the target values and number of considered levels, corresponding orth...

This thesis presents a process planning methodology for a rapid injection mold tool manufacturing system that involves additive and subtractive techniques, whereby slabs are sequentially bonded and milled using layered tool paths. Mold tools are grown in a bottom up fashion, eliminating the need for multi-axis machining operations (beyond three axes) and allowing small features in deep cavities...

The microstructure and residual stresses of an AA6040 Al to AZ31B Mg friction stir weld are studied using scanning electron microscopy and X-ray diffraction. The complex material flow promoted by the friction stir welding process results in a fine grained structure in the stir zone of both materials due to dynamic/recovery recrystallization. The interface between the materials is characterized ...

A liquation cracking mechanism of dissimilar Al alloys during the friction stir welding (FSW) is suggested in this study. To identify the mechanism, the precipitates were analyzed and Al-Mg-Cu phase diagrams were calculated. Electron backscattering diffraction (EBSD) analysis and electron probe microanalysis (EPMA) were also conducted. In the same manner as constitutional liquation, at high hea...