School of Materials Engineering (Articles)
http://dspace.unimap.edu.my:80/xmlui/handle/123456789/2203
2024-03-28T19:55:18ZPreparation and properties of porous calcium phosphate
http://dspace.unimap.edu.my:80/xmlui/handle/123456789/50154
Preparation and properties of porous calcium phosphate
Syed Nuzul Fadzli, Syed Adam; Ahmad Fauzi, Mohd Noor
In this study, preparation of porous calcium phosphate was involved the addition of sodium di-hydrogen phosphate, NaH2PO4 and di-sodium hydrogen phosphate, Na2HPO4 into the raw calcium phosphate powder. The sodium hydrogen phosphates salt was act as the porosity agent for the bio-ceramic samples preparation. This method using sodium phosphates salt produced samples with 20-70% porosities. After sintering the sample above 700°C with 4 hours soaking time, results showed that open-pores structure in the range of 1 to 400μm in size were obtained. The pores structure and sizes were depending on the percent addition of the additive and the level of sintering temperature. The compressive strength of porous samples was approximately ranging between 14.38 to 103.42 MPa.
Link to publisher's homepage at http://jere.unimap.edu.my
2008-01-01T00:00:00ZMechanical properties of bagasse fiber filled polypropylene composites
http://dspace.unimap.edu.my:80/xmlui/handle/123456789/50153
Mechanical properties of bagasse fiber filled polypropylene composites
Azlin Fazlina, Osman; Nur Sheli Akma, Ramli
The bagasse is a sugarcane waste generated in high proportions in the agroindustry.
In this study, bagasse fiber has been used as filler in polypropylene (PP)
matrix to develop the composite from polymer and natural fiber. Bagasse fiber
filled polypropylene (PP/BF) composites were prepared by using the Z-blade
mixer at processing temperature of 190°C and a speed of 35rpm with different
filler loading varying between 0% and 15% by weight. Maleic anhydride (MAPP)
coupling agent was used to improve the adhesion between the fiber and PP matrix.
The effect of coupling agent addition and fiber content on properties of PP/BF
composites was studied. Tensile strength and elongation at break increased with
increasing filler content while modulus of elasticity decreased for both coupled
and uncoupled PP/BF composite. The addition of bagasse fiber in PP has
decreased the flexural strength and flexural modulus for both coupled and
uncoupled PP/BF composites. However, coupled PP/BF composites showed
greater flexural properties compared to uncoupled PP/BF composites. Based on
swelling behaviour, it can be observed that the coupled PP/BF composites showed
lower water absorption rate compared to the uncoupled one. The presence of
MAPP as coupling agent resulted in decreased water absorption level and
enhanced mechanical properties for PP/BF composites.
Link to publisher's homepage at http://jere.unimap.edu.my
2008-01-01T00:00:00ZCopper-filled electrically conductive adhesives with enhanced shear strength
http://dspace.unimap.edu.my:80/xmlui/handle/123456789/39299
Copper-filled electrically conductive adhesives with enhanced shear strength
Ho, Li Ngee, Dr.; Hiroshi, Nishikawa
In this study, the effects of diethyl carbitol (diluent) and tertiary amines on the electrical, mechanical, and rheological properties of the Cu-filled polyurethane-based electrically conductive adhesives (ECAs) were investigated. Significant difference could be observed in the electrical resistivity and shear strength of ECA prepared with different amount of diethyl carbitol. Reduced electrical resistivity was found in ECAs prepared with addition of tertiary amines, but no obvious change was observed in the shear strength of the ECA joint. Rheological property of the ECA paste was investigated in order to understand the correlation of the viscosity of ECA paste and electrical resistivity and shear strength of ECA joint. Results revealed that decrease in viscosity of the ECA paste reduced electrical resistivity and enhanced shear strength of ECA joint. A Cu-filled polyurethane-based ECA with considerably low electrical resistivity at the magnitude order range of 10-3 Ωcm, and significantly high shear strength (above 17 MPa) could be achieved.
Link to publisher's homepage at http://www.asminternational.org/
2014-09-01T00:00:00ZDeformation and energy absorption characteristics of Biomass foam composites
http://dspace.unimap.edu.my:80/xmlui/handle/123456789/39127
Deformation and energy absorption characteristics of Biomass foam composites
Nur Azni, Mohd Azizan; Arzuria Sinar, Adnan; Firuz, Zainuddin; Supri, Abdul Ghani, Assoc. Prof. Dr.
Deformation and energy absorption characteristic of biomass foam composites are important in crashwortyness efficiency. The type of foam that had been used in this research is polyurethane (PU) foam with plant-based filler which are turmeric powder (Curcuma Longa), charcoal powder, henna powder ( Lawsonia inermis) and lemon grass powder (Cymbopogon) that give natural color to the composites. The percentages of filler was specified to 10% by weight. PU foam was prepared by reaction of natural oil polyol and isocyanate with a ratio of 1 to 1.1 by weight. The mixture was stirred with 1500 rpm and was poured into the mould when mixture starting to expand. Band saw was used to cut the sample with desired dimension. The characterization of filler was done using Fourier Transform Infrared Spectroscopy (FTIR). Compression was tested using Ultimate Testing Machine (UTM) and scale to weigh the sample. Composites with henna filler have ductile like behavior that proved in stress-strain curved that show the rough line in the graph. Other composites have rigid like behavior which have a smooth line in a stress - strain curve.
Link to publisher's homepage at http://www.ttp.net/
2014-04-01T00:00:00Z