Applied Mechanics and Materials Vols. 773-774

Abstract: This paper presents the melt flow index (MFI) of acrylonitrile butadiene styrene (ABS) and recycle ABS filament wire for Fused Deposition Modeling (FDM) machine. In this study, the effect of MFI on recycle ABS material was investigated experimentally based on the melting temperature, density, screw speed and material properties. The MFI result on ABS recycle in wire filament was investigated using Melt Indexer Machine (MIM). Based on the result obtained, it was found that, ABS recycle was increase the density and MFI results. It can be observed that, the higher temperature was melt the recycle ABS material through the MIM and extruder machine.

Abstract: This paper presents of Polymer Matrix Composite (PMC) as feedstock used in Fused Deposition Modelling (FDM) machine. This study discussed on the development of a new PMC material by the injection molding machine. The material consist of copper powder filled in an acrylonitrile butadiene styrene (ABS), binder and surfactant material. The effect of metal filled in ABS and binder content was investigated experimentally by the Melt Flow Index (MFI) machine. Based on the result obtained, an increment of copper filled in ABS by volume percentage (vol. %) effected on melt flow index results. With highly filled copper in PMC composites increase the melt flow index results. It was concluded that, the propensity of the melt flow allow an internal force in PMC material through the injection molding and FDM machine.

Abstract: Conductive ink has been widely used in many application of electronic parts. It normally comes in liquid form and will need to be cured usually by conventional oven or laser irradiation after it is drawn to expose its metallic contents. But, these curing processes suffer from numerous problems consist of laser is a costly process and a warping defect when cured using conventional oven. Thus, alternative process is prominent and DLP projector has been seen capable of polymerised photopolymer materials. By making use of its potential associated with a proper control of the light intensity, exposure time and distance, it could provides sufficent heat to cure conductive ink. This study investigates the curing process of silver conductive ink on polymer substrate using DLP projector light with a variation of curing time and distance. Electrical resistance, hardness and adhesion level of cured sample were measured to determine its functionality. The conductive ink is deposited on the substrate using a doctor blade method and Microsoft Powerpoint slide is used to shape the light image produced by the projector. It was found that the conductivity and curing level of the sample cured were higher at the distance which getting the sharpest light image. The performances of the samples were also greater as the curing time increased. DLP projector is able to cure the conductive track efficiently with shorter curing time apart from the cheap preparation and setup cost.

Abstract: This paper describes the analysis on the characteristics of semi-permeable membrane sound absorber. The effects of membrane surface tension on the sound absorption characteristics were investigated. The characteristics of the membrane absorber was measured experimentally in terms of Sound Absorption Coefficient, α and Noise Reduction Coefficient, NRC. The membrane is made of thin, flexible, semi-permeable latex material and the tests were carried out by using impedance tube method according to ISO 10534-2 standard. The results showed that the surface tension has significant influence on the sound absorption characteristics. For the parameters used in the laboratory work, specimen with unstretched surface tension has the best absorption performance.

Abstract: Currently in concrete technology a lot of materials were introduced to improve the quality and properties of concrete. Additional materials include the use of steel fibers into the concrete mix. With the used of steel fibers, it can enhance the strength of the concrete. In this research, two parameters will be investigated which is the volume friction of the steel fiber and the length of the steel fiber. End-hooked steel fiber with the length of 33 mm and 50 mm and the percentage of steel fiber 0.5 %, 1.0 % and 1.5 % used in this research. The size of the mold used is 100 mm x 100 mm x 100 mm. The characteristics during the fresh concrete were also investigated by conducting the slump test, compaction test and vebe test. All the samples has been cured in the water for 7^th, 14^th and 28^th days for the compressive strength test. Based on result, it was concluded that the optimum percentage of steel fiber in this report was 1.0 % for the end-hooked steel fiber with 33 mm length which provided the highest compressive strength at 28 days.

Abstract: There are many ways to control the vibration of plate structure. Conventional approaches that include structural alterations are frequently time consuming and costly. One of the common schemes is using vibration absorber attached to a structure. In this paper, a mathematical model is developed to determine the frequency response of fixed-fixed ends plate with attached vibration absorber. A finite element analysis was performed and compared with the theoretical predictions and showed that there was good resemblance. The results demonstrated that the addition of vibration absorber onto plate can attenuate vibration considerably at a constant frequency.

Abstract: ISO 14649 standard, commonly recognized as STEP-NC is a data model interface for computer numerical controllers. STEP-NC goes much further that G codes and has a more comprehensive data model that overcomes the lack of process information in ISO 6983 files (G codes programming). The STEP compliant approach brings the possibility to integrate the machine controller to the overall enterprise information network, with the intention of having bi-directional data flow. This will provide the novel capability for upstream feedback of information from the numerical controller to the design and process areas in the process planning and manufacturing. This paper presents the key concepts of the proposed STEP Convertor of the STEP-CNC Mapping System. The objective of the main system is to take a generic STEP file as the input to drive a CNC machine tool. The main system is broken down into two main sub-systems, STEP Convertor and STEP-NC Translator. This paper will focus solely on the information structure and conceptualization of the STEP Convertor.

Abstract: This present work investigated the perforated impact strength of woven kenaf fiber reinforced composites subjected to different projectile velocities. Three layers of woven kenaf mats were stacked with four different fiber orientations 0, 15, 30 and 45⁰. The composites are fabricated using hand-layout where the woven mats were placed into the mould with a polymeric resin. The wetted composites were compressed to squeeze out the excessive resin and to eliminate the void contents. The hardened samples were shaped into a standard geometry specified by ASTM D3763. Then, the composites were perforated impact using different speeds 1, 2 and 3 m/s. According to the present results, it was found that the perforated impact strength reduced when the impact velocity was increased. However, the impact strength of 15⁰ oriented composite was higher when compared with other types of composites.

Abstract: This present work investigated the perforated impact strength of woven kenaf fiber reinforced composites subjected to different projectile velocities. Three layers of woven kenaf mats were stacked with four different fiber orientations 0, 15, 30 and 45⁰. The composites are fabricated using hand-layout where the woven mats were placed into the mould with a polymeric resin. The wetted composites were compressed to squeeze out the excessive resin and to eliminate the void contents. The hardened samples were shaped into a standard geometry specified by ASTM D3763. Then, the composites were perforated impact using different speeds 1, 2 and 3 m/s. According to the present results, it was found that the perforated impact strength reduced when the impact velocity was increased. However, the impact strength of 15⁰ oriented composite was higher when compared with other types of composites.