Applied Mechanics and Materials Vols. 465-466

Abstract: Over this recent year, a growing population that increase the economic development, capacity of landfills and critical environmental impact are gaining the importance role of remanufacturing activities. Moreover, many durable products are disposed in landfills at the end of their useful lives without undergoing by any recovery process that affect the landfill space has been decreasing in all over the world including by our country. Remanufacturing is the process by which used products are returned to their new state with minimum waste and expenditure on materials and energy. This study focus on the concept concept of remanufacturing practice in automotive sector. Malaysians have been generated wastes at a manufacturing sector especially in the automotive sector. On top of that, the conventional remanufacturing systems that have been constructed in Malaysia are not widely marketed and lack of practical applications. This study provides a remanufacturing analysis for improvement to the automotive sectors on engine block. Furthermore, this study presents the information based on the discussion of Failure Mode and Effects Analysis (FMEA) to encourage the implementation of remanufacturing activities. By making the remanufacturing activities possible to implement efficiently, manufacturer may decrease their production costs, decrease refuse and landfill materials, and increase their quality management.

Abstract: Biopolymer foam was prepared based on vegetable oil and Polyol Flexible (Epoxy) with commercial Polymethane Polyphenyl Isocyanate (Modified Polymeric-MDI) with the different proportion ratio. This research is to study the acoustic property between different proportion ratio of biomonomer and epoxy. The acoustic property of biopolymer foam was examined by using an impedance tube test according to ASTM E-1050 of sound absorption coefficient (α). Based on the result obtained, mostly the values of α were consistent at the samples F. It was observed that, sample F gave the highest value of α that is 0.997 at of 3500Hz. Sample F from ratio 100:0 from epoxy to biomonomer and gave the best sound absorption than the other foam. So, different ratio give different α at different frequency (Hz).

Abstract: Wood dust filler-polymer foam composite has been studied and proved to have ability to absorb sound. In this study, treated rubber and Meranti wood dust named as RA and MA respectively was use as the filler. This study was developed to compare the behavior of sound absorption based on treated filler and particle size of wood dust. By choosing the size of 355 and 710 μm, three different percentages has been selected which is 10%, 15% and 20% for both type of wood dust. These samples has been tested by using Impedance Tube test for sound absorption coefficient (α) measurement and Noise Reduction Coefficient measurement (NRC) and Scanning Electron Microscopy (SEM) to determine the diameter of pore for selected size and type of wood dust-polymer foam composite. The pore size and structure was influence the sound absorption behavior of each sample. 355 μm-polymer foam composite of every percentage loading shows the uniform pore structure as compared to 710 μm of particle size. NRC results shows that increasing pore size has decrease the NRC value. It is therefore, concluded that the sound absorption coefficient for eachsound absorbing material, with different sizes of wood dust particles, types of wood dust and the percentages of wood dust loading in polymer foam matrix effect the sound absorption behavior.

Abstract: Waste cooking oils are problematic disposal especially in the developed countries. In this paper, waste cooking oil is used as raw material to produce foam. The purpose of the study is to develop the high density solid biopolymer (HDB) by using hot compression moulding technique based on flexible and rigid crosslinking agents. Physical properties such as Scanning Electron Microscope (SEM) and density of HDB were examined. The acoustic study of HDB sandwich layups of flexible (F) or rigid (R) has been measured using an impedance tube test according ASTM E1050 standard up to four maximum sandwich lay ups of F and R HDB in different arrangement. It was revealed that the arrangement sandwich layups of FRRF HDB sandwich gives the lowest sound absorption coefficients. The resonance frequency for RFR, FRF and FRRF were shifted to the left except for RFFR. The highest increment was 35.7 %, observed from RFR compared to the three layers of sandwich HDB. For the conclusion, RFR HDB showed that could absorb more sound, thus having higher noise reduction coefficient (NRC) than the other sandwich layups HDB at low frequency.

Abstract: Metal matrix composite is composite material that combines the metallic properties of matrix alloys and additional element to reinforce the product. This paper evaluates the machining performance of uncoated carbide and coated carbide in terms of surface integrity during end milling of LM6 aluminium MMC. The parameter of cutting speed, feed rate and axial depth of cut were kept constant at 3000 rpm spindle speed, 60 mm/min feed rate and 0.5 axial dept of cut. The radial depth of cut were varied from 0.01mm to 0.1 mm. The results indicated that uncoated carbide show the better performance in terms of surface roughness and surface profile, as compared to coated carbide. On the other hand, coated carbide cutting tools suffered with built-up-edge formation at the tool edge, hence caused shearing effect and deterioration at the tool-chip interface. This study is expected to provide understanding of machining metal matrix composites based materials.

Abstract: Legal and public pressures have urged companies and firms to practice good environmental policy. Apart from that, growing environmental consciousness among consumers has also evolved into a potential marketing opportunity that many companies deem valuable. In order to effectively manage a companys environmental policy, linking it closely to purchasing activities can potentially be a helpful way. In this paper, fuzzy axiomatic design (AD) approach is used to address the issue of green supplier selection. A case study is presented to demonstrate the utilization of fuzzy AD principles in analyzing qualitative environmental performances of suppliers with the consideration of all sub-criteria. The proposed approach is able to produce indicative results in terms of information content and is capable of identifying the most eligible supplier among three alternatives. This signifies that the application of fuzzy AD approach in the area of green supplier selection is feasible and is worth further exploration.

Abstract: Welding parameters are directly influenced by the work material properties. Thermal properties such as thermal conductivity and melting point are very important to estimate the range of power required and the allowable scanning speed. However, when two or more different materials are involved, modifying lasing parameters are not enough to counter the problems such as imbalance melting region and weak adhesion of contact surface. To counter this problem, the characteristics of welding beads formation for both materials need to be clarified. In this study, comparison of welding beads constructed using the same scanning parameters were done to understand the different and similarity of melted region for the both materials. Actual welding of the both materials were done under different offset distance to obtain a balanced melting area and well mixed melting region.

Abstract: This study is an approach to investigate the viable impacts of screw manufacturing. At the same time, choose the suitable material and selected manufacturing process of screw by considering environmental aspects without sacrificing the economic aspect. It is important to the organisation to improve the environmental aspect. Therefore in this study, the decision making was focused on economic aspects to produce the synergy results between economic and environmental impact. The parameters involved were types of material and manufacturing process of screw which using the available data of environmental and production volume. The two different manufacturing approaches being evaluated were machining and forging process. The types of material concerned for forging process encompassed low carbon steel, alloy steel stainless steel, and aluminium alloy. On the other hand, for machining process, the material being considered in screw manufacturing were cast iron, low carbon steel, alloy steel, stainless steel and aluminium alloy. The information of environmental impacts that generated from SolidWorks Sustainability tool and screw production cost were calculate using Manufacturing cost model, both information was used in Analytic Hierarchy Process (AHP) analysis to obtain local priority of economic and environmental impacts. Then, the ranking of both global and local priorities from economic impact and environmental impacts had enabled the determination of appropriate material used for those selected screw manufacturing process. As result, low carbon steel was chosen for forging process whereas cast iron was excelled in machining process, at the same time, stainless steel was not suggested to be used in both two processes.

Abstract: The development of Rapid Prototyping (RP) gave the consumer the ability to form prototype or a component of the prototype that can be directly used in assemblies and product testing for short or medium production with the least time consumed. The purpose of this paper is to study the dimensional accuracy and surface roughness for RP part as a master pattern for Investment Casting (IC) process. The material that been used is Polylactic acid (PLA) using a technique of Fused Deposition Modeling (FDM). The effects of internal pattern structure and part orientation during fabrication on the part master pattern can analyze from the response analysis. Results shows that PLA/FDM produced better accuracy and surface roughness when the part is fabricated with internal pattern structure compare to hollow structure. The internal pattern structures improved the quality of part and capable to supporting the design so that less warping or shrink. Part that built with 90o part orientation produced better accuracy and surface roughness compare to 0o part orientation.

Abstract: Hole making process is not strictly to the drilling technique where others machining could also influence to the quality in CFRP hole.Therefore, helical milling process becomes as an alternative method to produces bore on CFRP plate thus minimizing the defects. The common defects on CFRP are delamination, splintering and cracking. Meanwhile, if the CFRP stacking together with aluminum plate, burr at exit hole of aluminium plate is produced. Therefore, it is essential to control the critical machining parameters to assure a good quality of the hole. The main objective of this project is to improve the hole quality of CFRP/AL stack in terms of surface roughness using helical milling technique. In addition the cutting force and temperature will be measured as well. There are three levels of cutting speeds; two levels of feed rate and depth per helical path are made accordingly to helical milling characteristics. It was found that all tool design exhibit comparable performance for helical milling process on CFRP/Al stack.