Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : stir casting


Characterization and Mechanical Properties of the ZA-12 Hybrid Composites Reinforced with Nano Ceramic Particles

Aveen K. Yawer; Niveen J. Abdulkader; Dr. Ahmed A. Zainalaadbeen

Engineering and Technology Journal, 2021, Volume 39, Issue 4A, Pages 642-652
DOI: 10.30684/etj.v39i4A.1945

In this work, nanosized Boron nitride and silicon carbide reinforced ZA - 12 matrix hybrid composites were produced using stir casting technique with using of aluminum scrap (AA 2024), pure Al (electrical wires) and zinc scraps. Microstructure Observation was revealed by using scanning electron microscopy, and the analysis showed a uniform distribution of (SiC and BN) hybrid nanoparticles for the Zn-Al matrix. Also, an optical microscope was used to display the dendritic structure and reinforcement particles that dispersed uniformly in the matrix. Mechanical tests results confirmed that the hardness and the compression was increased with increasing the hybrid nanoparticle's percentage, whereas the wear rate decreased as the reinforcing materials increased. Since nanoparticles restrict dislocation movement, the mechanical properties are enhanced. The improvement ratio in hardness after addition was 26%., and in wear rate was 24% and for the compression strength the improvement was (19%).

Effect of ZrO2 Addition on Microstructure and Mechanical Properties of Al-Zn-Mg Alloy Matrix Composite

Israa A. Aziz; Russul S. Bedien

Engineering and Technology Journal, 2020, Volume 38, Issue 12, Pages 1751-1757
DOI: 10.30684/etj.v38i12A.336

Aluminum – based metal matrix composite are widely used in industrial applications compared with conventional and unreinforced alloy. The composite materials usually exhibit a higher strength both at elevated and ambient temperature, as well as wear resistance. The production of composite materials which contain different weight percentage of ZrO2 (0.5, 1.5 and 2.5wt %) by stir casting process. The mechanical properties of the base alloy and composite were evaluated by using tensile and hardness tests. The microstructure inspection by optical microscopy, scanning electron microscope and energy dispersive spectroscopy (EDS) were utilized to study the fracture surface topography. The results represent that the hardness, strength of yield and tensile strength increased with increasing the weight % of ZrO2 to 2.5 % while the elongation decreased. The microstructure inspection by optical microscope shows that the dendrites structure and the particles distribution in matrix without any voids. Furthermore, the grain size refining with the weight percentage of weight reinforcement elevated.

Study of the Corrosion Behavior of Zinc-Aluminum Alloy Matrix Composite Reinforced with Nanosilica Produced by Stir Casting

Fatima A. Adnana; Niveen J. Abdul Kader; Mohammed S. Hamza

Engineering and Technology Journal, 2020, Volume 38, Issue 3A, Pages 375-382
DOI: 10.30684/etj.v38i3A.435

In this investigation, Zn-Al alloy metal-matrix nano composites that
reinforced via various weight percentages (2%, 4%, 6%, and 8%) of
nanosilica (SiO2) particles were fabricated applying the technique of stir
casting. Behaviors of the corrosion of the unreinforced alloy and
reinforced composites were measured utilizing a potentiostat test in a (3.5
wt.% NaCl) salt solution. The optical microscopy was employed to
investigate the surface microstructure of the composite. Microstructure
analysis manifested that the uniform distributions of the reinforcing
particles in the composites are alike, consisting of a dendritic structure of
the zinc alloy matrix with an excellent reinforcing particles steady
dispersion. The improved results of the corrosion resistance for the metal
matrix composites showed an excellent resistance to corrosion than the
matrix in the (3.5 wt.% NaCl) solution. Raising the weight percentage of
the reinforcement particulates of nansilica (SiO2) reduced the composites
rate of corrosion

Processing and Properties of ZA-27 Alloy Metal Matrix Hybrid Composite Reinforced with Nanonitrides

Fadhil A. Hashim; Niveen J. Abdulkader; Kateralnada F. Hisham

Engineering and Technology Journal, 2020, Volume 38, Issue 1, Pages 57-64
DOI: 10.30684/etj.v38i1A.1597

In general, internal vibrations within the pipelines caused by fluids being passing through a pipeline system can cause. These pipeline system can damage by the sudden amplified vibrations that were not considered at the design of the system, and flow induced vibrations resonate with the pipes natural frequency. Therefore, it is important to predict and identify the pipeline system vibrations during its lifetime. In this study by using MATLAB code as a CFD solver, it studied the forced and free vibrations caused by fluid flows at Reynolds number ranged as 0 < Re < 2500 for laminar flow and ranged as 104 < Re < 105 for turbulent flow. The working fluid has chosen as of (Al2O3, TiO2, SiO2 and water) with different nanoparticle volume fraction of (0 to 2% vol.). These fluids flow in simply supported pipe with different lengths and diameters. The results presented the effect of pipe and fluid parameter upon the fluid critical velocity and fundamental natural frequencies. The results showed that the pipe natural frequency increased with increasing with decreasing the pipe length and diameter. In addition, it showed that the pipe natural frequency decreased when using the different nanoparticle depressed in the water and with increasing the volume fraction.

Characterization of AA 6061–Alloy Composites Reinforced by Al2O3 Nano Particles Obtained by Stir Casting

Hussain J. AL Alkawi; Abdul J. Owaid; Batool Kadhim H.

Engineering and Technology Journal, 2018, Volume 36, Issue 7A, Pages 792-797
DOI: 10.30684/etj.36.7A.12

The aim of this work is generated a Nano materials having good mechanical properties for 6061AA-alloy.Fivewt% of Nano particles (Al2O3) (20-30nm grain size) were adoptees (1, 1.5, 2, 2.5 and 3wt% AL2O3).The Nano composites were manufactured by stir casting technique. The mechanical properties of Nano composites were obtained at room temperature and was found that the matrix hardness is improved by 35.36%, matrix ultimate by107%, yield by36.84% and ductility by 12% at 1.5wt% AL2O3.Also it was obtained that all the mechanical properties of the Nano composites are higher than that of metal matrix. The above improvements are due to less porosity, high uniform distribution and good bounding between metal matrix and Al2O3.

Effect of B4C/Fly Ash Addition on Wear and Mechanical Properties of Al-Cu-Mg Alloy

I.A. Alkadir; L.S. Salim

Engineering and Technology Journal, 2017, Volume 35, Issue 4, Pages 301-310
DOI: 10.30684/etj.35.4A.1

This research studied the effect of adding fly ash and boron carbide (B4C) particulates reinforcement on the mechanical properties and wear resistance of Al- 4.5% Cu- 1.18% Mg matrix alloy. Stir casting method has been used to fabricate the alloy and hybrid composite samples containing 2wt% of B4C and 5, 10, 15،20 wt % fly ash. The x-ray inspection revealed the dispersion of intermetallic compounds (Al2Cu,MgO and SiO2) Also, the mechanical properties have been evaluated, the results showed an increase in the tensile and yield properties with the increase of weight percentage of fly ash content up to 15 wt%, but the elongation decreased, while the hardness increased. Wear rate examination has been concluded by using pin on disc apparatus under different loads of (5, 10, 15) N, sliding velocities (1.413, 2.827, 4.241) mm/sec, and different times of (5, 10, 15) min. The results showed decrease in wear rate at 20% fly ash composite sample when compared with other composites samples and base alloy.

Effect of The Reinforcing by WC on Microhardness, Roughness and Corrosion Behavior of Al-12Si Alloy

Hiba Anwer Abdullah

Engineering and Technology Journal, 2016, Volume 34, Issue 15, Pages 2891-2896
DOI: 10.30684/etj.34.15A.10

This work investigated the effect of Tungsten Carbide as reinforcement with 1, 2 and 3 wt.% on some properties of matrix Al-12Si alloy. Al-12Si/WC composites were fabricated by stir casting method. Micro hardness and roughness have been tested to investigate the role of WC reinforcing. Corrosion behavior of these composites also investigated in 0.2M HCl solution using the potentiostat instrument.
The results show a good incorporation between the matrix and WC particles with probability to form Al12W and Al4C3 phase in addition to eutectic structure of Al-12Si alloy. The micro hardness was increased with increasing the weight percent of WC, while the roughness was decreased due to the better interfacial bonding. Corrosion protection properties of composites were better than that of base alloy due to the behavior of WC as a cathodic site which reduces the dissolution of metals from the metallic surface.