Showing 3 results for Emamy
M. Alipour, S. Mirjavadi, M. K. Besharati Givi, H. Razmi, M. Emamy, J. Rassizadehghani,
Volume 9, Issue 4 (December 2012)
Abstract
In this study the effect of Al–5Ti–1B grain refiner on the structural characteristics and wear properties of Al–12Zn–3Mg–2.5Cu alloy was investigated. The optimum amount for Ti containing grain refiners was selected as 2 wt.%. T6 heat treatment, (i.e. heating at 460 °C for 1 h before water quenching to room temperature and then aging at 120 °C for 24 h) was applied for all specimens before wear testing. Dry sliding wear resistant of the alloy was performed under normal atmospheric conditions. The experimental results showed that the T6 heat treatment considerably improved the resistance of Al–12Zn–3Mg–2.5Cu alloy to dry sliding wear.
K. Tavighi, M. Emamy, A. R. Emami,
Volume 11, Issue 4 (December 2014)
Abstract
This study was undertaken to investigate the effects of Cu and solution heat treatment on the microstructure and hardness of cast Al-Al4Sr metal matrix composite. Different amounts of Cu (0.3, 0.5, 1, 3 and 5 wt.%) were added to the composite. Specimens were heat treated at 500 °C for 4 hours followed by water quenching. Microstructural studies were assessed by the use of optical microscope, scanning electron microscope (SEM) and x-ray diffractometry (XRD). The results showed that addition of 5 wt.% Cu reduces the length of large needle-like Al4Sr phase and refines the microstructure. In addition, the presence of Cu-intermetallics increases hardness of the composite. Cu mainly forms θ phase which segregates at the grain boundaries. Heat treatment partially dissolves Cu-intermetallics and homogenizes the distribution of θ phase in the matrix.
M. Amuei, M. Emamy, R. Khorshidi, A. Akrami,
Volume 12, Issue 3 (September 2015)
Abstract
In this study, Al2014 alloy refined with Al-5%Ti-1%B master alloy was prepared by strain-induced melt
activated (SIMA) process. The main variables of the SIMA process were cold working, holding time and temperature in
semi-solid state. Cold working was applied on specimens by upsetting technique to achieve 10%, 20% and 30% height
reduction. Cold worked specimens were heat treated in semi-solid state at 585 °C, 595 °C, 605 °C, 615 °C, 625 °C and
635 °C and were kept in these temperatures for different times (20 and 30 min). Observations through optical and
scanning electron microscopy were used to study the microstructural evaluation. The results revealed that fine and
globular microstructures are obtained by applying 30 % height reduction percentage and heat treating in 625 °C for
30 min. Comparison between refined and unrefined Al2014 alloy after applying SIMA process showed that Al-5%Ti-1%B master alloy has no significant effect on average globule size but makes the final structure more globular.