Advanced Materials Research Vols. 622-623

Abstract: The aim of this research work is to study the influence of wear parameters on the adhesive wear behaviour of aluminium matrix composites (AMCs). It consists of A413 aluminium alloy as the matrix material and particulate fly ash of 3%, 6% and 9% by weight as the reinforcement material. Stir casting technique was used to fabricate the AMCs. The distribution of the fly ash particles in the matrix phase was investigated using the SEM image. The wear tests have been carried out using a pin on disc machine according to the ASTM G99 – 05 specifications. Wear surfaces were analysed using the images captured through Video measuring machine. It was found that load has the highest influence on wear rate followed by sliding distance, sliding speed, and weight percentage of reinforcement.

Abstract: The paper presents the results of experimental investigation on the characterization and analysis of mechanical properties of composites formed. Three aluminum metal matrix composites reinforced with 10 wt% of B₄C, SiC and Al₂O₃ particles were processed. The stir casting method followed by hot rolling was used for fabrications of aluminium 7075 metal matrix composites, being one of the cost effective industrial methods. Experimental results show nearly a uniform distribution and good dispersion of reinforced particles within aluminium matrix. Both tensile strength and hardness are enhanced by incorporation of reinforcement particles into the matrix. Scanning electron microscope (SEM) analysis was done to study the good dispersion of particles and surface characteristics.

Abstract: Copper Composites reinforced with tungsten particles were prepared Powder Metallurgy Process. Cylindrical preforms with initial theoretical density of 85% was prepared using a die and punch assembly with a hydraulic press. The preforms were sintered in an electric muffle furnace at 750°C, 800°C, 850°C, and subsequently furnace cooled and then the specimens are hot extruded to get 92% theoretical density. The tribological behaviour of copper and composites was studied on a pin-on-disc tester. The pins were slid against a hardened steel disc under dry ambient conditions. The wear measurements showed that Cu -5W at 750°C extremely high wear loss. However, addition of 5% W particles appeared to improve the adhesive wear resistance of copper significantly under the applied loads of 5–15 N.

Abstract: Wide spread applications of composite materials have been significantly growing in aerospace, naval, space, and automotive industries. Drilling of such materials is a challenging task because of differential machining properties and checking the quality of hole is significantly a great attention. In this paper, experimental investigation on prediction of hole quality characteristics of aluminum matrix composite (AMC225xe) during drilling process. The influence of process parameters such as speed, feed rate and coolant flow rate on the surface finish and circularity were investigated during the experimentation. The experiments were conducted according to the Taguchi’s L9 array design using process parameters. The quality of the hole characteristics were measured using roughness tester and CMM. Regression analysis has been carried out for prediction of hole quality characteristics from the experimentation. It is observed that the predicted results are good correlation with measured values. Also, the results indicate that the feed rate is the most influencing parameter for drilling of AMC225xe.

Abstract: Geogrids are used as reinforcement materials for soil foundation structure in the geotechnical applications. Also, geogrids have the excellent tensile strength and modulus and therefore, geogrids can show the good reinforcement function within the soil foundation structure that the loads are concentrated. However, geogrids don't have the excellent efficiency to control the migration and loss of fine soil particles to be passed due to the large apertures (opening size).The new concept of reinforced geotextile composites, which can show both functions of reinforcement and separation/drainage and was manufactured by combining nonwoven geotextiiles and geogrid or geonetusing adhesive or thermal bonding process. Geotextile-Geonet Composites compose of geotextile-geonet-geotextilesandwich use for separation and filtration functions. Hence the objective of this study is to manufacture geocomposite for easy installation and better stability of sandwich material in soil condition. This geocomposites are evaluated for its performance.

Abstract: The delamination is a major problem associated with the drilling of chopped glass fiber reinforced polyester (GFRP) composites. It reduces the structural integrity of the material, results in poor assembly tolerance and has the potential for long term performance deterioration. Thus it is important to evaluate the process capability of drilling on this material. It will thereby reveal the spectrum of delamination to be accepted from the view point of process capability for a chosen range of material thickness, drill diameter, speed and feed rate combinations. In the present analysis, therefore, Taguchi loss function is derived for the particular process based on the experimental data. Process capability index is then evaluated. The range of delamination factor is determined based on the consideration that process capability index should be one or more. The results are presented.

Abstract: Although fiber-reinforced polymers (FRP) have until now been largely applied to various fields of engineering, these materials have also been used in many technical applications, especially where high strength and stiffness are required, but with low component weight. Among various natural fibers, banana fiber is of particular interest in that its composites have high tensile strength, high tensile modulus, and low elongation at break beside its low cost and eases of availability. In this study, banana fiber and glass fiber reinforced polyester Resin composites were prepared using hand lay up technique . Experiments are conducted to compare and to find the effect of fiber volume fraction on mode I fracture toughness of both composites.

Abstract: The amount of produced construction and demolition waste grows constantly and the current utilisation won’t be sufficient in the future. Thus it is inevitable to support further utilisation of these materials and enquire after more possibilities of its use. A new sphere for utilisation of the recycled materials in cement based composites open polymeric fibres of high strengths. Their use in production of the composite material change the brittle structure to the ductile one that is able to resist tensile stressed after cracking. The article presents findings from a study and analysis of the results of an experimental programme focused on the production of fibre reinforced concrete in which natural aggregate has been substituted with masonry or concrete recyclate.

Abstract: Generally, as for the material of catheter, a soft characteristic is necessary so as not to damage vascular wall etc. On the other hand, responsivity and enough rigidity are required for the surgical operations such as myocardial infarction or cerebral infarction. Therefore, the catheter, which is made of soft nylon resin and is reinforced with thin stainless wires so called “braid”, is chosen as the subject of this study. The purpose of this study is to reveal the effect of braid on the mechanical property of the catheter by investigating the relationship of the stress relaxation and the relative angle between the braid and the principal axis of stress. Especially, in order to investigate the stress relaxation under combined loading, the experiments of two-stage step strain for tension and torsion are carried out with different deformation paths. Consequentially, the phenomenon of the stress relaxation reduces with the relative angle becomes smaller. Moreover, the numerical model under two-stage step strain is proposed in this paper, and the validity of this model is confirmed by comparing the calculated results with the experimental results.

Abstract: Discontinuously reinforced cast metal-matrix composites are increasingly attracting the attention of aerospace, automotive and consumer goods industries. In this study, SiC particle reinforced aluminium alloy is selected to produce metal matrix composites (MMC) using different of parameters blade angle and stirring speed and composition of SiC reinforcement. Mechanical test, metallographic analysis and fracture analysis will be conducted to investigate mechanical properties of material and to observe particle distribution of SiC reinforcement and fracture properties respectively with varies angles and stirring speed of impellers and different composition of SiC reinforcement. Metallographic analysis on composition records at low speed, there exist a particle collection and gas existence on the specimen. At blade angles of 300, increasing on stirring speed and composition of SiC reinforcement may result better of particle distribution. For mechanical test, different composition of SiC reinforcement, blade angle and stirring speed will be affecting a mechanical property of material. The result of the experiment showed at blade angle 300, stirring speed 100rpm and 10% composition of SiC reinforcement give better result of hardness, ultimate strength, energy absorption, microstructure and fracture of composite. For this study, it proved that at the lower blade angle and the increment on stirring speed and composition of SiC reinforcement give a better result on particle distribution of SiC reinforcement, fracture and mechanical properties for A1-MMC.