Thermal stability of twin-roll cast Al–Fe–Mn–Si sheets accumulative roll bonded at different temperatures

Accumulative roll bonding (ARB) allows production of large amounts of ultra-fine grained materials. Therefore, ARB is suitable for industrial applications. Refinement efficiency is improved when the input materials contain fine particles, such as in twin-roll cast (TRC) alloys. The effect of the ARB temperature on bond strength, microstructure, properties and thermal stability of a TRC Al–Fe–Mn–Si alloy was studied. After two cycles at 200 °C, grain sizes of 0.4–0.8 μm are achieved along with areas of grain sizes of 0.08–0.3 μm. The hardness increases significantly during first two ARB cycles and afterwards it increases less. Processing at higher temperatures produces a better bonding but smaller hardness increments. Partial recrystallization during heating above 250 °C results in a less effective grain refinement depending on the annealing temperature and on the number of cycles. The thermal stability of the samples processed at 250 °C is better as compared to higher temperatures and to conventional cold rolling.