Abstract
The CMA-powder and the Al-CMA composite (CMA=Al₇₃Mn₂₁Fe₆) have been studied with the intention to characterize the influence of selected technological procedures (milling for 80 h, extrusion at 400 °C under 500 MPa, compaction at 550 °C for 0.5 h, and annealing at 550 °C for respective 0.25 and 0.5 h) on the phase evolution inside CMA-areas and at Al/CMA interfaces. In the investigation X-ray diffraction and scanning electron microscopy including energy dispersive X-ray spectroscopy were used. It was shown that CMA-powder consisting of T(HT)+γ₂ became totally amorphous after 80 h of milling. During extrusion, compaction, and annealing of the Al-CMA composite, the originally amorphous CMA particles were found to transform into crystalline phases at the assistance of aluminium diffusion towards the CMA-area. At the Al/CMA interfaces on the CMA side, IMC-areas (IMC=intermetallic compound) were formed consisting of Al₆(Mn,Fe). T(LT)+Al₄ (Mn,Fe)+Al₆(Mn,Fe) phases were identified in the CMA-areas after the annealing of the Al-CMA composite for 0.5 h at 550 °C.

Key words
metal-matrix composites, interfaces, scanning electron microscopy, energy dispersive X-ray spectroscopy, extrusion, annealing

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