Influence of technological parameters on evolution of phases in Al-CMA composites prepared by powder metallurgy

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. K e y w o r d s : metal-