This study is mainly about the drilling of carbon-epoxy laminates. Variation of cutting parameter such as feed rate (50,100 and 150 mm/min) and speed(400,800,1200 rpm) were tested in this study. 6 different laminates orientation (0°/0°/0°/0°, 45°/45°/45°/45°, 0°/45°/0°/45°, 45°/0°/45°/0°, 0°/0°/45°/45° and 45°/45°/0°/0°) were tested in order to see which one is the best. HSS twist drill with 4mm diameter was use in this study. The damage of the composites was seen under digital microscope. The aim of this study is to find the minimum force and the minimum damage mechanism i.e.: entry and exit delamination. The drilling process with different parameter of cutting and the orientation were carried out in order to see the influenced of this parameter to the force and the damage mechanism. The general factorial was used to randomise the number of experiment.

Carbon fibre reinforced polymer (CFRP) is replacing metallic components and become a valuable material that has been used in many industrial applications including biomedical, marine and automobile. This is due to their excellent performance in term of reliability, high strength and light weight. However, the machining of CFRP is challenging because the abrasiveness of their reinforcement component often resulted in high tool wear rate. This experiment was carried out to investigate the effect of cutting parameters (cutting speed and cutting condition) on tool wear of uncoated tungsten carbide end mill tool, and to observe the wear mechanism of the carbide tool mill during milling of CFRP. In this study, machining test was carried out with the presence of coolant to aid in removing the cutting heat during machining. The effect of cutting speed of 132 m/min, 151 m/min and 170 m/min with a constant feed rate of 2100 mm/min during milling process of CFRP by using uncoated tungsten carbide end mill tool were discussed. Based on the result obtained, it was found out that the value of tool wear at cutting speed of 170 m/min is higher compared to the wear value at cutting speed of 132 m/min due to the high frequency friction of tool against machined surface. Analysis of tool wear using Scanning Electron Microscope (SEM) found out that the primary wear observed is abrasive wear due to the rubbing action between the tool and the surface of workpiece. The cutting tool is observed to have the lowest tool wear when low cutting speed is implemented along with the presence of coolant.

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Fused Deposition Modelling (FDM) is an additive manufacturing (AM) process that produces a physical object directly from a CAD design using layer-by-layer deposition of the filament material that is extruded via a nozzle. In industry, FDM has become one of the most used AM processes for the production of low batch quantity and functional prototypes, due to its safety, efficiency, reliability, low cost, and ability to process manufacturing-grade engineering thermoplastic. Recently, the market is flooded with the availability of low-cost printers produced by numerous companies. This research aims to investigate the effect of different porosity levels on a scaffold structure produced using a low-cost 3D printer. Comparisons of these porous structures were made in terms of Von-Mises strain, total deformation, as well as compressive stress. Various porosity levels were created by varying printing parameters, including layer height, infill density, and shell thickness by slicing the initial solid CAD file using Repetier Host 3D printing software. Finite Element Analysis (FEA) simulation was then performed on the created scaffold structures by using Ansys Workbench 19.2. The simulation result indicates that the greater porosity level will result in higher total deformation of the structure. Meanwhile, the compression test shows that the minimum strength value obtained was favourable at 22 MPa and had exceeded that of the trabecular femur (15 MPa). However, its porosity level (maximum at 52%) was still below that of the minimum threshold of porosity level of 70 percent. However, the printing parameters currently used can be adjusted in the future. Therefore, it was deduced that the low-cost 3D printer offers promising potential to fabricate different porosity structures with multiple outcomes.