03099ntm a2200289 a 4500 vtls000098091 KUKTEM 20251117113338.0 161107t2016 my a f abm 000 0 eng d THE0005420(Local) 201905151504 hanafiah 201710091631 aishah 201611071551 saini 201611071543 saini UMP FKP .S93 2016 r Thesis Mohamad Syahmi Shahrom Direct recycling of aluminium alloy 6061 and 7075 employing cyclic extrusion compression back pressure technique / Mohamad Syahmi Shahrom Kuantan, Pahang : UMP, 2016 xiii, 128 p. : ill. (some col.) ; 30 cm. + 1 CD-ROM Faculty of Manufacturing Engineering Thesis (Master of Science) -- Universiti Malaysia Pahang – 2016 Bibliography: p. 111-115 The direct recycling process is an alternative method of recycling waste of chip aluminium without melting the materials as compared to conventional recycling technique (secondary production). The cold compaction stage is the most crucial process of the direct recycling process. The billets density, b achieved through the cold compaction stage significantly influences the hardness (mechanical properties) and chip boundaries (microstructural properties). The problem of conventional compaction (direct compaction) presents low of b. The objective of this study is to develop the Cyclic Extrusion Compression Back Pressure (CECBP) technique to improve the b which influences the hardness and chip boundaries of aluminium alloy 6061 and 7075 chips in the direct recycling process. Taguchi Method was used as a tool to analyse and optimise the CECBP factors namely the pressure, P back pressure, Pb cycle time, tc and holding time, th. Different lubricant strategy techniques (flood, dry and minimum quantity lubricant (MQL) were used to obtain different types of aluminium chips. Conventional compaction (direct compaction technique) was used to get b value. The MQL showed the highest b results compared to flood and dry technique. The experimental results suggested that the CECBP technique is able to improve cyclic billets density cyb to 12.11% (AA6061) and 5.45 % (AA7075) compared to direct compaction technique. It is also established that the cyclic specimen hardness, Hcys and chip boundaries for both aluminium alloys improved when cyb value increased by using regression analysis. Pressure is identified to be the most significant factor in influencing the properties of cyb, cys and Hcys. In conclusion, CECBP technique had successfully improved the cold compaction stage for a direct recycling process and can used as direct recycling process of aluminium in industry. Faculty of Manufacturing Engineering Dissertations Universities and Colleges Dissertations Theses http://ecollib.ump.edu.my/24312/ Library access only 0 0 lcc 0 1 20000 20000 2019-09-04 0 FKP .S93 2016 r Thesis 0000111111 2019-09-04 00:00:00 1 2019-09-04 THESIS 0 0 lcc 0 1 20000 20000 2019-09-04 0 CD 9912 | FKP .S93 2016 r Thesis 0000111112 2019-09-04 00:00:00 1 2019-09-04 THESIS VIRTUA40 7108 7114 VTLSSORT0080*0200*0400*0900*1000*2450*2600*3000*5000*5020*5040*5200*6100*6500*6501*8560*9992