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Abstract:A hydroxyapatite is known as one of vital materials and common use in biomedical field and concentrated in clinical area. In relation to the above, the development of hydroxyapatite powder becomes an attractive research lines due to simplify in produce it. Thus in this paper the researcher stress out about Hydroxyapatite powder gained from the natural sources or so called as the waste of Tilapia bone and scales. The raw bones of and scale were undergo to crushing process to form in powder size (0.2 mm) then analysed by X-ray Diffraction (XRD) to identified the mineralogy of raw bone. Moreover the powder of fish bone and scales also go through to Scanning Electron Microscope (SEM) machine to analyse the microstructure of the powder while EDS act as device to determine the chemical composition of the sample powder. Sample powder then forward calcination process at selected temperature range to as a cheaper method in obtained hydroxyapatite raw sources. The range ofcalcination temperatures are between 800˚C to 1000˚C.The sample preparation were analysed in both condition before and after calcination process by using XRD, SEM and EDS.The HAP crystalline composition of tilapia bones for raw powder and at 800 ˚C are similar with HAP pattern (JDS 00-009-0432) and the chemical reaction is Ca 5 (PO4) 3 (OH) then at temperature 900 and 1000 similar to HAP pattern (JDS 00-055-0592) with chemical reaction equal to Ca 10 (PO4) 6 (OH) 2 .

Mixing homogeneity and the feedstock rheological characteristic for optimal binder formulation in metal injection moulding is evaluated between Polypropylene (PP) and Sewage fat (SF) or Fat Oil Grease (FOG). Difference powder loading of SS316L also being used here to determine the possibility of the best binder formulation selected could be optimised for optimal powder loading base on rheological characteristic analysis. Two binder formulations of PP to SF being selected here are 60/40 and 70/30 accordingly with the powder loading of 60% and 55% for each binder formulation. The analysis will be base on viscosity, shear rate, temperature, activation energy, flow behaviour index and moldability index. It is found that rheological result shows all the two binder formulations with both powder loading exhibit pseudoplastic behaviour or shear thinning where the viscosity decrease with increasing shear rate. Feedstock viscosity also decrease with increasing temperature indication of suitability for moulding. Results from all the analysis conducted shows that the volumetric powder loading of 60% with binder volumetric of 60% for PP and 40% for SF contributes significant stability and suitability for optimum powder loading.

Rapid prototyping (RP) process offers a promising economical way as a sacrificial pattern in investment casting (IC) at high speed and low cost for low volume part manufacturing. However direct sacrificial RP pattern have encountered shell cracking during burnout process due to polymer based materials. Shell mould thickness was need to be concerned to have strong enough to withstand RP part expansion for employing direct method. The aim of present research was to compare the efficacy of different shell thickness for aluminum casting part fabricated from acrylonitrile butadiene styrene (ABS) and acrylate based material made from FDM and MJM respectively. The hollow RP pattern has been used directly to produce ceramic moulds. The feasibility of ceramic mould has been assessed in term of burnout ability and crack defect. Dimensional accuracies and surface roughness of the castings part have been observed in this investigation. Result shows thicker mould with proposed stuco procedure resulted without any crack defect for botRP part and no residual ash remained when firing higher than 870°C of temperature.In addition, FDM produced better accuracy for overall mould thickness, but MJM have better surface roughness. Therefore both direct RP pattern were suitable to be used in IC process with proposed shell thickness.

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A thermoelectric generator (TEG) using Seebeck effect to generate electrical energy in a residential application encompasses a case study of a test rig consisting of a concrete shingle as case study material. This paper explores its behavior and response to changes in temperature throughout the day. Four TEGs in series are mounted on the underside of a shingle. The measurement of the voltage and current response were made to determine the power generated. Using National Instruments as a data acquisition device with thermocouple probes to gather all the necessary data of which are discussed in the paper. From the experiments, the modules were able to generate up to 65.22 µW at 138Ω. This shows a considerable potential of TEG application in residential areas, as they are scalable.

Abstract. Injection molding is probably the most important method of processing of consumer and industrial goods, and is performed everywhere in the world. In this paper, Taguchi Methods was used to define the optimization of process parameter for an injection molding machine to produce a dumbbell product from High-density Polyethylene (HDPE) + natural fiber (Kenaf). Taguchi Methods with L9-3 4 approaches will be used in this work where two different formulation of material will be tested to find the best formulation and its parameter setting. Here, an orthogonal array (OA) and signal-to-noise (S/N) ratio are employed to analyze the effect of injection molding parameter. The significant of formulation and parameter setting from injection molding will be evaluated through the strength value of the specimen. Standard ISO R527-2 test method will be used. Results show that changes in the parameter setting will give different tensile strength value. The optimum parameter setting was set based on the S/N ratio. For each formulation, optimum parameter setting has been achieved by using highest mean S/N ratio and it can be calculated manually or by using Minitab software.