Preparation of homogeneous Al-In hyper-monotectic alloys with copper mould rapid solidification method

Homogeneous Al-In hypermonotectic alloys have been fabricated by copper mould rapid solidification technique and the effects of the melting process, the composition and the cooling rate on the microstructure have also been investigated. The results show that, for the alloys with mass fraction of indium less than 30%, the homogeneous alloy melt can not be obtained unless the holding time is not less than 40 min at 1173 K. The alloy sheets with at least 4 mm, in which the fine In particles disperse in the matrix, can be produced with the copper mould rapid solidification method. The size distribution of In particles within Al matrix is bimodal. Under the same cooling rate, the particles' average size increases with the rising contents of In. Under the same composition, the particles' average size decreases with increasing cooling rate.