M.M. Hamdan

Tensile Properties of Arenga pinnata Fiber-Reinforced Epoxy Composites

The aim of this study is to determine the tensile properties of Arenga pinnata fiber as a natural fiber and epoxy resin as a matrix. The Arenga pinnata fibers were mixed with epoxy resin at the various fiber weight percentages of 10%, 15%, and 20% Arenga pinnata fiber and with different fiber orientations such as long random, chopped random, and woven roving. Hand lay-up processes in this experiments were to produce specimen test with the curing time for the composite plates is in the room temperature (25–30°C). Results from the tensile tests of Arenga pinnata fiber reinforced epoxy composite are that the 10 wt.% woven roving Arenga pinnata fiber showed the highest value for maximum tensile properties. The tensile strength and Youngs modulus values for 10 wt.% of woven roving Arenga pinnata fiber composite are 51.725 MPa and 1255.825 MPa, respectively. The results above indicate that the woven roving Arenga pinnata fiber has a better bonding between its fiber and matrix compared to long random Arenga pinnata fiber and chopped random Arenga pinnata fiber. Scanning electron microscopy (SEM) tests were carried out after tensile tests to observe the interface of fiber and matrix adhesion.

The Influence of Alkaline Surface Fibre Treatment on the Impact Properties of Sugar Palm Fibre-Reinforced Epoxy Composites

The aim of this study is to determine the impact properties of sugar palm fibre-reinforced epoxy polymer composite after introduce the alkaline treatment to the fibre. The fibre was treated by alkaline solution with 0.25 M and 0.5 M NaOH solution for 1 hour, 4 hours, and 8 hours soaking time. Hand lay up process was used to prepare the composite specimens with 10% volume fraction. The dimensions of the specimen used to carry out the test were adapted from ASTM D256 for Izod Impact testing. The higher impact strength of treated sugar palm fibre reinforced epoxy composite took place at 0.5 M NaOH solution with 8 hours soaking time, i.e., 60 J/m with improving by 12.85% from untreated composite.

Motorcycle helmet: Part I. Biomechanics and computational issues

Abstract This paper is devoted to review the current status related to motorcycle helmet crash studies from biomechanics and computational point of view. The importance of motorcycle helmet performance on statistical background was reviewed. The paper is divided into two main sections: in the first section, the biomechanics issues are highlighted and the head injury classifications are presented. The injury mechanisms for different injury types are analyzed and the related helmeted-head impacts were identified. The injury tolerances for the head main components presented with an insight into the current controversies among the different limits particularly rotational acceleration effects on the brain and the DAI brain damage type. In the second section, insights into the computational issues that are critical to the understanding of the helmet safety are presented. Some recent examples in which computational techniques used are also reviewed. Finally, directions for future research are also highlighted.

Motorcycle Helmet Part II. Materials and Design Issues.

Abstract The main objective of this paper is to formulate a methodology, which could be used for material selection and basic design of motorcycle helmets. The importance of simplified solutions to motorcycle helmet material selection and design are first highlighted. Two methods are presented. The first approach is based on energy absorption theory for packaging design and also was used for bicycle helmets design with some adjustments. This method is reviewed and modified to cope with the motorcycle helmet design requirements. The second approach is also based on energy absorption principle. This method was developed for packaging design but the same principles could be employed to the motorcycle helmet problem. It was found that the two approaches have the same energy absorption principles but differ in the way of formulation and utilization. These differences could have significant effect on the results particularly the energy per unit volume calculation. However, both procedures could be used as a useful tool for the helmet foam material selection and helmet preliminary analysis and design. Using these energy approaches together with advanced computational techniques could reduce the lead-time of helmet design and manufacture.

Study of Interfacial Adhesion of Tensile Specimens of Arenga Pinnata Fiber Reinforced Composites

The aim of this study is to determine the interfacial adhesion of Arenga Pinnata fiber and epoxy matrix after undergoing a tensile test. The specimens of Arenga Pinnata fiber reinforced epoxy composites were prepared at various fiber weights of 10%, 15% and 20% with different fiber orientations such as woven roving, long random and chopped random. Hand lay up process was used to prepare the specimens. Interfacial fiber-matrix adhesion study was carried out using scanning electron microscope (SEM). The interfacial adhesion study of tensile strength specimens of Arenga Pinnata fiber reinforced composites reveals that the woven roving fiber composites gave good interface adhesion between the fiber and the matrix as compared to long random and chopped random fiber reinforced epoxy composites.

Development of a CAD/CAM system for the closed-die forging process

Abstract The application of computer-aided engineering (CAE), computer-aided design (CAD), and computer-aided manufacturing (CAM), is essential in modern metal forming technology. Thus, the process of modelling for the investigation and understanding of deformation mechanics has become a major concern in recent and advanced research, and the finite element method (FEM) has assumed increased importance, particularly in the modelling of deformation processes. This work is devoted to the development of a CAD/CAM system for the closed-die forging process. The system development consists of three stages: namely, metal flow simulation, die failure analysis and design optimisation, and the development and implementation of a machining code. In the first stage, the FEM was used to simulate the axisymmetric closed-die forging process of copper material. The method is used to study the metal flow; die filling, retaining the non-linearity involved in the large change in the geometry; the continuous change in the contact surface condition; and the isotropic material work-hardening characteristics. In the second stage, a finite element analysis and optimisation algorithm is developed to examine the die fatigue life and to optimise the die design. The finite element analysis in the first and second stage was carried out using commercially available finite element software called LUSAS. In the third stage, a machining code for the optimised die is developed and implemented using CAD/CAM software called UniGraphics and CNC machine.

A Literature Review of Pineapple Fibre Reinforced Polymer Composites

A literature review of the development, mechanical properties and uses of pineapple leaf fibre (PALF) reinforced polymer composites is presented in this paper. The mechanical properties of PALF composites as determined by various researchers are discussed, together with chemical, thermal and physical properties. Both thermosetting and thermoplastic resins have been used as matrices for PALF composites. Most of the work surveyed used short PALF. Manufacturing methods such as injection moulding, hand lay up and compression moulding were usually employed for making composite samples.

Motorcycle helmet: Part III. Manufacturing issues

Abstract In this paper the motorcycle helmet manufacturing aspects are reviewed. Firstly the details of shell manufacturing are presented. Both the thermoplastic and the composite shell manufacturing techniques are presented with specific mentioning of the advantages and disadvantages to each type from the manufacturing point of view. Secondly, the manufacturing methods of different foam types used as motorcycle helmet liners are described and their characteristics are discussed.

Internal Pressure Carrying Capacity for Different Loading Modes of Filament-Wound Pipes from Glass Fiber-reinforced Epoxy Composites

Development of a low-cost filament-winding machine is initially described in this paper. The filament-winding machine was used to fabricate composite pipes and the materials used were woven glass fiber and epoxy resin. The pipes were tested under three loading modes, namely mode I (hoop pressure loading), mode II (biaxial pressure loading), and mode III (biaxial pressure with axial compressive loading). The results reveal that filament-wound composite pipes should be wound at 75° for hoop pressure loading (mode I), 55° for biaxial pressure loading (mode II), and 85° for biaxial pressure with axial compressive loading (mode III).

The crashing behaviour of motorcycle basket under impact loading

The finite element method (FEM) is employed to investigate the collapse of motorcycle basket under the action of dynamic axial loading. A detailed finite element model of a common motorcycle basket used in Malaysia has been developed. The validation of the finite element analysis is performed by experimentally captured deformation stages of the basket using video camera. The implications of the finite element simulations together with the test results are discussed in relation to the overall impact deformation of the basket.