Browsing by Author "Anasyida A.S."

Now showing 1 - 5 of 5

Dry wear behavior of cooling-slope-cast hypoeutectic aluminum alloy
(2016) Thuong N.V.; Zuhailawati H.; Anasyida A.S.; Huy T.D.; Dhindaw B.K.
This study investigated the effect of use of a cooling slope on the microstructure, hardness and wear behavior of Al-7Si-Mg alloy. The Al-7Si-Mg alloy was cast with and without a cooling slope at a pouring temperature of 6408C. Examination with optical and electron microscopes showed that the microstructure of cast samples using the cooling slope comprised fine and globular primary a-Al phase with homogeneous distribution of eutectic phase, while conventionally cast samples featured coarse and dendritic primary a-Al phase. The wear resistance of the cast sample was significantly better with cooling slope casting. The wear mechanism was found to be a combination of adhesion, delamination, oxidation and abrasive wear for both cooling slope- and conventionally cast samples. The wear mechanisms of cast samples both with and without cooling slope are similar and follow Archard's law. The cooling slopecast samples with fine and globular ?-Al phase, high hardness and low specific wear rate (K') showed the highest wear resistance of 10.08 � 10-5 mm3 N-1 m-1. � Carl Hanser Verlag GmbH & Co. KG.
Effect of Initial Microstructure on Properties of Cryorolled Al 5052 Alloy Subjected to Different Annealing Treatment Temperatures
(2018) Anas N.M.; Dhindaw B.K.; Zuhailawati H.; Abdullah T.K.; Anasyida A.S.
Al 5052 alloy sheets were subjected to different pre-annealing temperatures (150, 200, 250, 300, and 350��C) prior to cryorolling. The process resulted in Al 5052 alloys with different initial microstructures. The pre-annealed alloy sheets were compared with a cryorolled sample not subjected to pre-annealing. The thicknesses of the alloy samples after cryorolling was reduced by 30%. The pre-annealed cryorolled samples exhibited low crystallite size, and high lattice strain. Among them, the cryorolled sample pre-annealed at 300��C had the lowest crystallite size, and the highest lattice strain. Changes in initial microstructure of this sample resulted in a significant improvement in its hardness (88�Hv), tensile strength (333�MPa), and corrosion resistance. The sample had the highest corrosion resistance among the cryorolled samples. � 2018, ASM International.
Investigation of the microstructure, mechanical and wear properties of AA6061-T6 friction stir weldments with different particulate reinforcements addition
(2019) Abioye T.E.; Zuhailawati H.; Anasyida A.S.; Yahaya S.A.; Dhindaw B.K.
Welding of heat-treated AA6061-T6 often results in mechanical and wear properties deterioration because of the dissolution of the strengthening precipitates at the joint. Enhancement of these properties has been accomplished for non-heat treatable aluminium alloys through the addition of reinforcement particles in the joint. However, its application to AA6061-T6 is scarce. In this work, the microstructure, hardness and wear resistance of AA6061-T6 friction stir welded joints reinforced with SiC, B4C and Al2O3 particles were investigated while the base metal and the unreinforced welded joint were utilised as the control. Aluminium matrix grains refinement which improved with increased particle distribution homogeneity occurred in the entire welded joints. All the reinforced welded joints showed improvements on the unreinforced joint in terms of hardness and wear resistance because of the particles high hardness and substantially increased grain refinement that occurred in the reinforced welded joints. Due to B4C extremely high hardness and homogeneous distribution in the joint, B4C reinforced joint exhibited the highest improvements in hardness (42%) and wear rate (67%) at low-load condition. However, at high-load condition, SiC followed by the Al2O3 reinforced joints showed the least wear rate even lower than the base metal. The matrix hardness significantly influenced the wear performance at low-load but the overall effects of the reinforcement particles were predominant at high-load condition. The reinforcements' additions reduced the wear rate of the welded joint by up to a factor of 1.7 and 1.9 at low and high load conditions respectively. � 2019 The Authors.
The role of roller speed on solidification of Al-Mg-Si alloy during twin roll strip casting
(2015) Zuhailawati H.; Yusof M.M.; Anasyida A.S.; Almanar I.P.; Dhindaw B.K.
In the production of aluminum alloy strips for packaging industry twin roll strip casting technique is now being extensively employed. The twin roll caster has advantage of the energy saving, low cost equipment and rapid solidification. The present research aimed to investigate the microstructure and hardness of twin roll strip cast aluminum alloys strips by varying the speed of roller cast. Al-Mg-Si ingot was melt in an induction furnace. Once it melted, the liquid was poured into a crucible attached to a twin roller cast to maintain the liquid temperature at 700�C. Molten alloy was poured in the gap between the copper rollers to produce the strips. The rotational speed of the cast rolls was varied from 60-30 rpm. During this process, the melt solidified to form strips. A specimen of 50 mm length cut from the cast strips was subjected to physical and mechanical characterization. Variation in hardness and microstructure of the produced trip were discussed. � (2015) Trans Tech Publications, Switzerland.
Solidification of aluminum copper alloy during twin roll strip casting
(2014) Hussain Z.; Nasir L.M.M.; Anasyida A.S.; Dhindaw B.K.
Twin roll casting is an innovative route to produce thin metal strip directly from the melt. The paper, presents solidification characteristics of twin roll cast, Al-Cu eutectic alloys. Molten alloy was poured in the gap between the copper rollers to produce the strips. The rotational speed of the rolls could be varied from 10 rpm to 100 rpm. During this process, the melt solidified to form strip. A specimen of 50mm length cut from the cast strips was subjected to physical and mechanical characterization. Variation in hardness and microstructure of the produced trip is explained as a comparison to normal casting. � (2014) Trans Tech Publications, Switzerland.