Abstract

Heatsink is one of the solution to optimize the performance of smart electronic devices. Copper and its composites are helping the electronic industry to solve the heating problem. Copper-graphene heat sink material with enhanced thermal conductivity is the ultimate goal.Powder injection molding (PIM) has advantages of high precision and production rate, complex shape, low cost and suitabality for metal and cremics.PIM consists of four sub sequential steps; feedstock preparation, molding, debinding and sintering. Feedstock preparation is a critical step in PIM process. Any deficiency at this stage cannot be recovered at latter stages. Therefore, this research was carried out to investigate the injectability of copper and copper graphene composite using PIM. PEG based multicomponent binder system was used and the powder loading was upto 7vol.% less than the critical powder loading was used to provide the wettability of the copper powder and graphene nanoplatelets (GNps). Corpper-graphene feedstock contained 0.5vol.% of GNps . To ensure the homogeneity of GNps within feedstock a unique technique was addopted. The microscopic results showed that the feedstock is homogeneous and ready for injection. The viscosity-shear rate relationship was determined and results showed that the addition of 0.5vol.% of GNps in copper has increased the viscosity upto 64.9% at 140˚C than that of pure copper feedstock. This attribute may be due to the large surface area of GNps. On the other hand, by increasing the temperature, viscosity of the feedstock was decreased, which was recommended for PIM. The overall viscosity and share rate lies within the range recommended for PIM process. It is clear that both feedstocks showed pseudo plastic behaviour which is suitable for PIM process. In the pseudo plastic behaviour, the viscosity decreases with the shear rate. It may be due to change in the structure of the solid particles or the binder. The molding results showed that both copper feedstocks were successfully molded and free from the physical defects.

Details

Title
Rheological study of copper and copper grapheme feedstock for powder injection molding
Author
N Emira Binti Azaman 1 ; Raza, M Rafi 2 ; Muhamad, N 1 ; Akhtar, M Niaz 3 ; A Bakar Sulong 1 

 Department of Mechanical and Materials Engineering, Universiti Kebangsaan Malaysia, Bangi, Selangor Malaysia 
 Department of Mechanical and Materials Engineering, Universiti Kebangsaan Malaysia, Bangi, Selangor Malaysia; Department of Mechanical Engineering, COMSATS Institute of Information Technology, Sahiwal Pakistan 
 Department of Mechanical and Materials Engineering, Universiti Kebangsaan Malaysia, Bangi, Selangor Malaysia; Department of Physics, COMSATS Institute of Information Technology, Lahore Pakistan 
Publication year
2017
Publication date
Feb 2017
Publisher
IOP Publishing
ISSN
17426588
e-ISSN
17426596
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2573735030
Copyright
© 2017. This work is published under http://creativecommons.org/licenses/by/3.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.