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Thixoforming is a promising method that offers several advantages over both liquid and solid processing. This process utilizes semi-solid behaviour and reduces macrosegregation, porosity and forming forces during the shaping process. Microstructural and mechanical characterization of 0.3, 0.5 and 1.0 wt% graphene nanoplatelet (GNP) reinforced A356 aluminium alloy composite fabricated by thixoforming was investigated. Stir casting was employed to fabricate feedstocks before they were thixoformed at 50% liquid. The microstructure was characterized and evaluated by field emission scanning electron microscopy with an energy dispersive X-ray detector and X-ray diffraction. Mechanical testing, such as microhardness and tensile testing, was also performed to estimate the mechanical properties of the composites. The incorporation of 0.3 wt.% GNPs in Al alloy increased by about 27% in ultimate tensile strength and 29% in hardness. The enhancement in tensile strength is primarily attributed to load transfer strengthening due to the uniform dispersion of these GNPs within the Al matrix, which promotes effective load transfer during tensile deformation, and GNPs’ wrinkled surface structure. Simultaneously, the addition of GNPs enhances the grain refinement effect of the Al alloy matrix, resulting in a grain size strengthening mechanism of the GNPs/Al composites. The results reveal that thixoformed composite microstructure consists of uniformly distributed GNPs, α-Al globules and fine fibrous Si particles. The composites’ grains were refined and equiaxed, and the mechanical properties were improved significantly. This study creates a new method for incorporating GNPs into Al alloy for high-performance composites.

Running is a method of terrestrial locomotion allowing humans to move rapidly on foot, which related to the movement of lower limb. But for flat feet, running or walking for a long period will give them a high-risk associate with a foot pain. In order to reduce the foot pain, an arch orthotics insole is advised to be wore by the flat feet. This paper provides an extensive study on orthotics insole focusing on sport usage for flat feet. For this silicon rubber Orthotics Insole is designed with sufficient arch support, sufficient thickness, metatarsal pad, heel pad, heel cup and ergonomics dimension specification. The objectives of this research are to design and improve the efficiency of orthotics insole for flat feet focusing on sport usage. Both new orthotics insole and existing insole will be evaluated by using electromyography (EMG) that will record the electrical potential which generated by muscle cells. The output of time domain feature and frequency domain feature for both insoles will be analyzed and compared. This Orthotics Sport Insole ideal to be used by flat feet especially during their sport activity specifically running in order to reduce muscle pain to prevent injuries.

The potential of binary Mg-Ca alloy as biodegradable material is considerable interest in implant application among researchers. This research was conducted to investigate the effect of different forging temperature and forging speed on the hardness, microstructure and corrosion rate of Mg-0.7%Ca. The experiment was established by preparing the alloy sample with 0.7%wt calcium content. The forging process was carried out under four different temperature variations of 140°C, 180°C, 220°C, and 260°C (±10°C) with two different speed;25 and 45 strokes per minute (spm). The samples microstructure was examined by optical microscope and scanning electron microscope (SEM) equipped with energy dispersive X-ray (EDX). The mechanical properties of the forged samples were measured in its hardness and plastic deformation ability along with samples cold-working percentage. The corrosion rate was determined by performing the electrochemical test in simulated body fluid. This research found that increases of forging temperature and forging speed provide a higher rate of recrystallization and Mg2Ca compound precipitation results in greater hardness, increase deformation and reduce the cold-working percentage. However, the investigated factors still led to a high corrosion rate compared to a previous study and consequently, reduce the feasibility of the alloy in implant application for biodegradable material.

Nowadays, most of the time people will using cooking oil to bake, fry and other type of cooking. There are many types of cooking oil such as olive oil, palm oil, canola oil, vegetable oil and etc. Normally, only two or three times the oil can be used for fry. After that, the oil will throw away. The disposal of used cooking oil is an important factor for the waste-management. Most people will dump the used cooking oil in the kitchen sink. This will led to blockage to the pipe and contaminate water. Without people realise, used cooking oil can be recycled in to soap for general purposes. The aim of this research is to develop a semi-automatic machine for making soap by using used cooking oil as main ingredients. There were a lots of process involved such as how to gain the voice of customer (VOC), concept selection, detail design, fabrication and testing process in order to verify the quality and time taken to produce the soaps. This machine can be used in every kitchen of household and not for mass production. Meanwhile, user can make their own soap for general purpose such as to wash floor, car and drain. Moreover, this can save environment.