Microstructure and Properties after Friction Stir Processing of Twin-Roll Cast Al–Mn–Cu–Be Alloy

We studied the effect of friction stir processing (FSP) on microstructure and properties high-speed twin-roll cast strips made an experimental Al–Mn–Cu–Be alloy. The samples were examined using light, scanning, transmission electron microscopy, microchemical analysis, X-ray diffraction, indentation testing. During FSP, rotational speed varied, while other parameters remained constant. uniformity increased with growing speed. In zone, several processes took place, most important were: recrystallisation matrix grains, fragmentation primary intermetallic particles Al15Mn3Be2 their more uniform distribution in fracture, dispersion eutectic icosahedral quasicrystalline phase (IQC), transformation tiny IQC into τ1-Al26Mn6Cu4 precipitation Al–Mn–Cu precipitates. thermomechanically affected new dislocations formed as well grains. heat-affected dissolution θ’-Al2Cu precipitates occurred. hardness variation was not severe between zones.