Abstract. In this day and age, zirconia ceramics are used widely in the medical field as biomaterials for the replacement of damaged body parts. This is because zirconia is one of the closest replacements for bone tissue. However, there were a few cases regarding the failure of zirconia ceramic hip transplants. To overcome this issue, composite materials are being studied as they are able to combine different properties which are not present in a material. This study of Y-TZP/stainless steel 316 composite is carried out with the idea of providing a solution for failure of zirconia implants and also an improvement in biomaterials which will benefit the biomedical world. The study aims to determine the effects on how the increasing of stainless-steel content in the composite will affect the relative density, Vickers hardness, fracture toughness and ageing resistance of the Y-TZP/stainless steel 316 composite. To carry out the research, the composite samples were prepared by mixing the powder of each samples according to their determined content with ethanol. After the powders were mixed, the powders were then pressed, followed by undergoing a Cold Isostatic Press process (CIP) and then it underwent sintering at its determined temperature. After sintering, the samples underwent grinding and polishing before being ready for testing. The outcomes of the research showed that as the sintering temperature and the content of stainless-steel increase in the composite, the fracture toughness and ageing resistance improved while the Vickers hardness and relative density decreased.

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Solar photovoltaic (PV) panels have been widely used to convert the renewable energy from the sun to electrical energy to power electrical loads but suffers from relatively low efficiency between 15% to 22%. Typically, the panels have an average lifespan of 25 to 30 years but could degrade quicker due to the panel overheating. Beyond the optimum working temperature of 25°C, a drop of efficiency by 0.4 to 0.5% for every 1°C had been reported. For solar PV applications in urban regions, passive cooling is beneficial due to limited amount of space and lower energy consumption compared to active cooling. A solar PV system with augmented cooling was conducted at a balcony of a condominium from 10am until 2pm. The solar PV system consisted of an Arduino controller, solar panel module, temperature sensor and LCD monitor. Reusable cold and hot gel packs were attached to the bottom of the solar PV. Both setups of solar PV panel with and without the cooling system were placed at the balcony simultaneously for measurement of temperature, output voltage and current. From this research, the outcome of implementing a cooling system to the solar PV increases the efficiency of the energy conversion.

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Abstract. Yttria stabalised Tetragonal Zirconia Polycrystalline (Y-TZP) has been extensively renowned for its vast outstanding contribution in medical field such as primary function for implant biomaterial which acts as restoration of damaged body parts. Nonetheless in the past decades, there have been various reported cases that point the failure of hip transplants involving material of zirconia ceramic. This eventually leads to the birth of this research project where it studied the properties effects of Y-TZP as it was added or doped with stainless steel 316 (SS316). In this research project, the parameter of weight percentage for stainless steel 316 (SS316) to be doped with Y-TZP were as follows; 0 wt%, 0.1 wt%, 0.5 wt% and 1 wt%. The outcome of this experiment then were measured and analysed as according to properties of relative density, Vickers hardness and fracture toughness. The experiment was conducted by firstly mixed the Y-TZP and SS316 powders together as according to the weight percentage of SS316 as well as addition of ethanol solution that act for medium of enhancement. The mixture then underwent compacting pressure bench press as well as Cold Isostatic Pressure (CIP) in order to produce the green sample. After that, the green sample underwent sintering process via pressureless sintering method at mentioned ranges temperature of 1250°C, 1300°C, 1400°C and up to 1500°C. Subsequently, the sample then underwent grinding and polishing process before proceeding to the measurement and analysis process. The outcome of the measurement and analysis process revealed that as the content of SS316 doped with Y-TZP increases as well as the increased in sintering temperature, the relative density and fracture toughness profound to be increased while Vickers hardness indicated as decreased.