Aluminum alloys have high potential as light structural materials. In this work light and electron
microscopy and X-ray diffraction were used to study the structure and phase composition of deformed
bulk samples from the Al-7075 and the Al-3003 alloys. Severe plastic deformation was carried out by
the dynamic channel angular pressing (DCAP). In this method the rate of deforming materials is estimated
to 103-105 s-1. The finite element method was used to model the deformation
process for samples when they moved through intersecting channels. Optimal process parameters to form
the uniform structure in the samples were determined. The resulting data of this studying indicate that
the formation of ultrafine-grain (UFG) structure is result from two mechanisms - a fragmentation in
multicomponent Al alloys (Al-7075) and dynamic recrystallisation in low-alloyed alloys (Al-3003).
Such different structure formation demonstrates a realization of two channels of elastic energy relaxation.
Thus, DCAP method can be applied effectively for production UFG (|
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