Si refinement by electromagnetic ultrasonic in an Al–Si alloy Haghayeghi, L.C. De Paula, E.J. Zoqui, “Si refinement by electromagnetic/ ultrasonic in an Al–Si alloy”, Journal of Materials Engineering and Performance Vol.26, issue 4, 2017, PP.1900-1907. The effects of electromagnetic stirring, ultrasonic treatment (UT), and their combination on the Si particles refinement in a hypereutectic Al-Si…
Crystallization and nucleation in liquid Al containing spinel seeds Write By Reza Haghayeghi Haghayeghi, M. Qian, “Crystallization and nucleation in liquid Al containing spinel seeds”, Materials Letters, 196 (2017) 358–360. Step-by-step in situ near-atomic-resolution observations were presented for initial crystallization or nucleation in a liquid Al-10Mg (wt%) alloy containing spinel (MgAl2O4) seeds. Ordering of…
Refinement/modification of Si via self-inoculation in an Al-Si alloy Write By Reza Haghayeghi Haghayeghi, E.J. Zoqui, G. Timelli, “Refinement/modification of Si via self-inoculation in an Al-Si alloy”, Journal of Materials Processing Technology Vol.252 (2018), PP.294-303. The alloy A390 was ultrasonically treated, and the resulting material was referred to as master alloy. The master alloy…
Duplex Nucleation in AZ91 and its high temperature properties Write By Reza Haghayeghi Saber, R. Haghayeghi, H. Najafi, P. Shahbeigi-Roodposhti, “Duplex Nucleation in AZ91 and its high temperature properties”, Journal of Engineering Materials and Technology, Vol.140 (2018), PP. 041002-1 to 6 The grain refinement of Mg–Al alloy AZ91 via carbon inoculation, including the…
Write By Reza Haghayeghi : Enhanced refinement and modification via self-inoculation of Si phase in a Hyper eutectic aluminium alloy The alloy A390 was ultrasonically treated, and the resulting material was referred to as master alloy. The master alloy was added into a non-treated A390 melt over two different levels: 10 and 20% by volume in…
Write By Reza Haghayeghi : Abstract. Melt Conditioned Direct Chill (MC-DC) casting is a new development for producing high-quality billets and slabs. In the MC-DC process, liquid metal is continuously fed into a MCAST (melt conditioning by advanced shear technology) machine, where the liquid metal is subjected to high shear rate and high degree of turbulence provided by…
Writing By Reza Haghayeghi There has been a great debate whether grain refinement is more effective when shearing above or below the liquidus. In this work, examination of the microstructural evolution in AA7075 alloy has been performed, after stirring above & below the liquidus. The results suggest that shearing above the liquidus is more effective….
Writing By Reza Haghayeghi: The influence of intensive shearing above liquidus on the Solidification Process, microstructural evolution and its effect on the final Microstructure for the Al–10 wt% Mg alloy were investigated and discussed thor- oughly. The effect of shearing was explored and was compared with non-sheared samples. The effects of relaxation (holding melt after…
Reza Haghayeghi Abstract: The effects of ultrasonic treatment (UT) and electromagnetic stirring (EMS) forces, individually and in combination, prior to high pressure die-casting of AA5754 alloy were assessed. The liquid of alloy was subjected to UT, EMS and the combined style and then transferred to the shot chamber. The grain size, mechanical properties, gas content…
Writing By Reza Haghayeghi : The effects of introducing ultrasonic vibrations prior to high pressure die casting have been experi- mentally investigated. Results suggest reductions of up to 73% in grain size and up to 5% on porosity levels due to cavitation, leading to enhanced structural performance. The typical values of ultimate tensile stress…