Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Wear Rate

Microstructure and Wear Rate of Yttria Reinforced Aluminum – Silicon Matrix Composites

Engineering and Technology Journal, 2010, Volume 28, Issue 23, Pages 1184-1195

In this research, composite materials of hypereutectic aluminum – silicon as a matrix reinforced with different volume fractions (2%, 4%, 6%, 8%) of Yttria particles with grain size between (50 - 75 μm) are prepared. The composites are prepared by vortex technique in which the particles were added to the melt then mixing it by mechanical stirrer then the mixture is poured in a metallic cylindrical molds. After that, the microstructure, Vickers hardness and wear rate were conducted. The results showed the existence of the reinforcement particles in
different amounts in the microstructure and an increase in the hardness for the prepared composites when compared with the unreinforced alloy. The results also showed a better particles distribution and higher hardness with increasing yttria volume fraction. The wear rate of the composites is reduced when compared with the unreinforced alloy due to the hardness increase. More reduction in wear rate was noticed with increasing the Yttria volume fraction, and the better added percent was (8%Y2O3).

Numerical Study of Forced Convection in Wavy and Diverged-Converged Ducts

Anmar M. Basheer; Sattar J. Habeeb; Waheed S. Mohamad; Qutaiba G. Majeed; Mohammed Y. Fattah; Jawad K.Oleiwi; Mohammed S. Hamza; Mayyadah Sh. Abed; Amjed J. Hamidi; Ahmed Alaa Ogla; Yaser Nabeel Ibrahem

Engineering and Technology Journal, 2009, Volume 27, Issue 7, Pages 1385-1403

A three-dimensional study of developing fluid flow and heat transfer through
wavy and diverged-converged ducts were studied numerically for a Prandlt number 0.7
and 5.85 and compared with flow through corresponding straight duct. The Navier-
Stokes and energy equations are solved by using control finite volume method.
Development of the Nusselt number in wavy and diverged-converged ducts are
presented for different flow rates (50


forced convection
numerical study
wavy duct
diverged-converged duct

A study of the Hardness and Wear Rate of Elastomer Composites Reinforced by Al2O3 and SiO2 Particles

Jawad K.Oleiwi; Mohammed S. Hamza; Mayyadah Sh. Abed

Engineering and Technology Journal, 2009, Volume 27, Issue 7, Pages 1422-1434

This research deals with the study the effect of adding the silica particles and
alumina particles separately with different ratio (5, 10, 15, 20, and 25 pphr) on the
hardness and wear rate of natural rubber NR and styrene butadiene rubber SBR. The
results show that the hardness increases with the increase the loading level of reinforcing
particles, while the wear rate decreases with the increase the loading level of the
reinforcing particles. The largest value of the hardness and the lowest value of the wear
rate were for styrene butadiene reinforced with 25 pphr of silica as compared with
natural rubber. Also the reinforcing by SiO2 increases the hardness and decreases the
wear rate more than of Al2O3.
The results indicated that the hardness and the wear rate for SBR and NR
reinforced by SiO2 and Al2O3 at (25 pphr) illustrated in the following table: