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A fin heat exchanger is a simple form of cooling device that is built for efficient heat transfer from one medium to another. Generally, it involves medium such as fluid to perform heat exchange via convective heat transfer. This study is aimed at investigating the effects of diverse designs (arrangements of the fins), qualities (the total surface area of the fin for heat exchange) and conditions (the surface characteristics) of fin heat exchanger on the degree of heat transfer from the experimental perspective. The fin heat exchanger was fabricated and tested. It was observed that by varying the arrangement and condition of the fins, the rate of heat transfer could be affected. However, varying the quality of the fin didn’t have much impact. Nevertheless, the quality aspect of the fin heat exchanger could play a significant role for heat exchanger of larger in scale and dimension. The coating, that is the condition of the fins, aided in decreasing the temperature at a much higher margin at all fan speeds.

This paper presents an investigation on the effect and optimization of machining parameters on the kerf (cutting width) and material removal rate (MRR) of titanium alloy (TI-6AL-4V) using wire electrical discharge machining WEDM with a brass wire diameter of 0.5mm. The experimental studies were conducted under varyingpulse-off time, peak current, wire feed and wire tension. The settings of machining parameters were determined by using Taguchi experimental design method. The multiple performance characteristics based on the statisticalbased analysis of variance (ANOVA) and grey relational analysis (GRA) was attempted. Analysis of variance was used to study the significance of process parameters on grey relational grade (GRG) which showed the most significant factor. The GRG obtained from the GRA was used to optimize the WEDM process. The optimum process parameters are determined by the GRG as the overall performance index. To validate the findings, confirmation experiment had been carried out at the optimal set of parameters, and the predicted results were found to be in good agreements with experimental findings. Improved machining performance in the WEDM process has been achieved by using this approach.

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This paper presents the performance of three-dimensional Puck failure criteria emphasising on the gradual degradation law to predict the structural responses, as well as the onset and propagation of failure due to different interface modelling technique. The proposed damage model is performed using Abaqus explicit analysis. Four different cohesive models are analysed using three-dimensional finite element model based on low-velocity impact loading. The structural responses are compared with experimental data taken from literature to measure the performance of such damage model. It is found out that the model adopted here responses well with test curves and demonstrates the high capability of predicting the damage in the direction of in-plane as well as out-of-plane in a composite laminate. The simplified model using combination of tie-cohesive layer technique demonstrated the balance performance between the quality of the result as well as calculation time.

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This paper presents an investigation on influences and multiple optimizations of wire-electrical discharge (WEDM) machining performances such as cutting rate, material removal, surface roughness and kerf width processed on titanium alloy material. The experimental studies were conducted under varying machining parameters namely pulse-off time, peak current, wire tension and wire feed. The experimental works were designed base on Taguchi design of experiment. The optimum multi-objective performance characteristics was determined using analysis of variance (ANOVA) coupled with grey relational analysis (GRA). ANOVA was used to study the significance of process parameters on grey relational grade which showed the most significant factor. The grey relational grade obtained from GRA was used to optimize the wire-electrical discharge machining process. To validate the findings, confirmation experiment had been carried out using the optimal parameters and the predicted results were found in good agreements with experimental finding. Improved machining performance in the wire electrical machining process has been achieved by using this approach.

Titanium metal injection molding (Ti-MIM) is coming ever closer to delivering its promise of high value markets, such as the aerospace and medical sectors. It is therefore an inspiration in this study to try to use palm stearin (PS) combined with backbone polyethylene (PE) for injection along with Ti-6Al-4V atomized powder. The uniqueness of PS is a potential binder system that can be used since it is very cheap material and highly available in Malaysia. The present work attempts to optimize the process parameters of thermal pyrolysis stage using Taguchi method of orthogonal array. Density is important characteristic in determine the quality of the brown part. Using these characteristics, the heating rate, temperature and soaking time are optimized in this study. The results show that no swelling or distortion was observed on the molded specimens on both binder systems. It was found that heating rate was the most significant factor followed by pyrolysis time and pyrolysis temperature. A verification test was also performed to prove the effectiveness of Taguchi technique after all the optimum parameters were determined. The optimization of thermal pyrolysis prepared in this study has enabled to improve the final density and mechanical properties of final part. Based on these results, sample displaying yield strength of 929.91 MPa and a plastic elongation of more than 12.15% were produced and meet the requirements of the ASTM B817-08.