Mohd Ahadlin Mohd Daud

Effect of Carbon Nanotubes on Properties of Graphite/Carbon Black/Polypropylene Nanocomposites

High chemical corrosion, low manufacturing cost and light of total mass of bipolar plate in Proton Exchange Membrane Fuel Cell (PEMFC) lead most of the PEMFCs researchers over the world attracted their interest to replace pure graphite or metal based bipolar plate with conductive polymer composites (CPCs) bipolar plate. CPCs is fabricate from the mixed of conductive fillers such as and Graphite (G) andCarbon Black (CB) had been incorporated in Polypropylene (PP) matrix for fabrication of electrical conductive polymer composite plate. Most researchers reported only at high loading of fillers (more than 90 wt.%), are gave electrical conductivity above 100 S/cm, which is target from Department of Energy (USA). Higher loading of fillers cause change in rheological properties and increase the difficulties in polymer processing. Thus will decreasing the electrical and mechanical properties of CPCs as bipolar plate. Therefore, in this study carbon nanotubes (CNTs) which have 1000 time electrical conductivity than copper wire are introduced into G/CB/PP composite to compensate above problems. But the main problems of CNTs, at high loading it tend to agglomerate and thus will affect the properties of CPCs. So that, small amount of CNTs which is 0.2, 0.4, 0.6 and 0.8 wt.% will be added into G/CB/PP composite. But weight percentage of CB and PP has been fixed which is 25 wt.% and 20 wt.% respectively and the weight percentage of G will various from 55 wt.% to 54.2 wt.% according to CNTs loading. The result shows that the G/CB/CNTs/PP composite with 0.2 wt% CNTs has the higher electrical conductivity 295.78 S/cm.

Effect of Different Filler Materials in the Development of Bipolar Plate Composite for Polymer Electrolyte Membrane Fuel Cell (PEMFC)

In Polymer Electrolyte Membrane Fuel Cell (PEMFC), bipolar plate is considered one of the most important components. Bipolar plate has a multi-functional in the fuel cell stack. The materials used in producing bipolar plate are greatly affecting its final properties. Through this study, the properties of bipolar plate composite will be observed. The based composition of this composite is 80% for multi-filler material and 20% binder material. Polypropylene (PP) will be used as binder material and for filler materials, Graphite (Gr) is the main filler and for the second filler materials its will vary with the usage of Carbon Black (CB), Iron (Fe), and Aluminum (Al) powder. The formation of this composite is produced through compression molding. The effect of different filler material loading on the properties such as electrical conductivity, bulk density and shore hardness are observed. The result showed the increasing of electrical conductivity as the increased the CB and Fe loading. But for Al, the result showed the decreasing of electrical conductivity as the loading of Al has been increased. Meanwhile the usage of CB clearly shown an improvement in electrical conductivity and able to meet the DOE target properties for development of PEMFC bipolar plate.

Influence of Heat Treatment on Impact, Hardness and Fatigue Strength of 6061 Aluminium Alloy

This paper presents effects of heat treatment on toughness, hardness and fatigue strength of aluminum alloy 6061. The alloy specimens were heat treated in the furnace at different temperature levels and holding times; and then cooled in different media (water and oil). The mechanical properties such as hardness, impact and fatigue were examined using standard method. Result shows that mechanical properties of aluminum alloy can be improved by the heat treatment. It was found that through ageing processes at temperature 160 °C for one, three and five hours, decreased the hardness, while increased the toughness. The fatigue strength was decreased when the number of cycles increased. The fracture surfaces between specimens have a different appearance before and after heat treatment.

Fracture Toughness of AZ61 Magnesium Alloy with Various Thickness

The critical fracture toughness parameter KΙC of AZ61 magnesium alloy was determined on the three point bent specimens with notch designed according to ASTM E399 standard. Five specimens having different thickness, i.e., 2, 4, 6, 8 and 10 mm were considered in order to evaluate the effect on fracture toughness. The stress intensity factor range ΔK was constant ~1x 10-8 for every specimen until the critical crack length reached half of the width of the specimens. The fracture test was done with the speed rate 0.12-0.15 MPa√m/sec until the specimens broke. The experimental results showed that the critical plain strain fracture toughness KΙC is 12.6 MPa√m and the highest plain stress fracture toughness KC is 16.5 MPa√m.

The Effect of Heat Treatment on Fatigue and Mechanical Properties of 6061 Aluminium Alloy

This paper investigated the effect of heat treatment on mechanical properties and microstructure of 6061 aluminium alloy. The aluminium alloys were examined in the heat treated conditions, using different quenching media, water and oil. The alloy was solution heat treated at temperature of 529oC for one, three and five hour respectively. Aging treatment was carried out at temperature of 160oC which is assumed to be the best temperature for ageing process. Hardness measurement was carried out using a Brinell Hardness Tester Machine. The results shows hardness and impact strength are inversely proportional to each other, as the hardness of 6061 aluminium alloy decreases and impact strength increases.

Preparation of Polymer Composite Bipolar Plate with Different Multi-Filler for Polymer Electrolyte Membrane Fuel Cell (PEMFC)

Polymer Electrolyte Membrane Fuel Cell (PEMFC) is an alternative energy system that has been verified with great potential for high power density, durability and cost effectiveness. Since the bipolar plate is the key component in PEMFC, the component must operate with multifunction and have a balance of properties, essentially well in both electrical and mechanical properties. At present, many different materials have been tested to be applied for bipolar plate in order to fulfill the balance in each property. In this work, the different material is tested and observed. Polypropylene (PP) is used as a binder material, Graphite (Gr) is used as a main filler and Carbon Black (CB), Iron (Fe) and Nickel (Ni) as the second filler. This composite is produced through compression molding and the effect of different filler material loading on the properties such as electrical conductivity, flexural strength, bulk density and shore hardness are observed. The result showed the increasing of electrical conductivity as the increased the CB and Fe loading. But for Ni, the result showed the decreasing of electrical conductivity as the loading of Ni has been increased. The targeted value also achieved for some certain degree of filler loading.

Effect pf Thermoplastic Polymer Waste (PET) in Lightweight Concrete

Contruction concrete that use of insulation wall in building construction faces some problems such as having high weight, very reflective sound, heat transfer (the effectiveness of heat conductivity) incompetence and mechanical properties (strength) constraints. The sounds which impinge the wall cannot be absorbed efficiently but instead gives high reflection. This causes some noise of high echo in a room. So a good acoustic insulation must be efficient in absorbing the sound. This project proposes lightweight concrete as a replacement for insulation wall. This lightweight concrete will be developed using thermoplastic polymer waste which is recycled plastic bottles, sand, water, and cement. This research used thermoplastic polymer waste which is PET (Polyethylene Terephthalate) material as the reinforcement material to replace small gravel in lightweight concrete. All its composition percentage of raw materials was divided into different samples composition. Its composition determines the performances of the samples in density, porosity and mechanical properties.