Advanced Materials Research Vol. 428

Abstract: In this study, nanoclay and multi-wall carbon nanotubes have been used as a dual filler in an epoxy matrix. In the design of the experiment (DOE) the Taguchi Method was selected to study the effect of the factors involved in this study. The effect of the clay/MWNT ratio, types of solvent, clay cation, composition of LENR, cure time and cure temperature on tensile properties of the epoxy nanocomposites were investigated. The confirmation experiment obtained from Taguchi analysis, achieved 57% improvement in tensile strength. X-ray diffraction (XRD) and transmission electron microscopy (TEM) revealed the presence of intercalated and aggregated structures. Due to the lower crosslink density of the system, a decrease in decomposition temperature and glass transition temperature was observed in the optimum sample.

Abstract: This article involves the use of [Ca (2,2′-bipyridine)₃]²⁺-intercalated montmorillonite as a potentiometric sensor to measure anions in aqueous solution. The [Ca (2,2′-bipyridine)₃]²⁺-intercalated montmorillonite was prepared by modification of an in situ solid-solid reaction, between natural Ca (II)-montmorillonite and 2,2′-bipyridine at a molar ratio 1:3. The formation of [Ca (2,2′-bipyridine)₃]²⁺- in the interlayer space of montmorillonite was confirmed by powder X-ray diffraction (XRD) and the existence of 2,2′-bipyridine was confirmed by the C:N ratio of the product compared with that of the 2,2′-bipyridine molecule. The potentiometric sensor was constructed by mixing [Ca (2,2′-bipyridine)₃]²⁺-intercalated montmorillonite with artificial graphite, polytetrafluoroethylene (PTFE) and carboxymethylcellulose (CMC) in an appropriate ratio. It was found that the sensor had higher sensitivity to S^2- rather than other anions, graphs of log [S^2-] vs voltage (mv) gave a slope 30.0 which was closed to theoretical value, 29.5. Activity of the [Ca (2,2′-bipyridine)₃]²⁺ sensor was verified by using sensor made from Ca (II)-montmorillonite as a reference. Reproducibility and precision of the electrode were also determined.

Abstract: For guiding production effectively and revealing rolling mechanisms, the analysis of rolling-pressure distribution regulation is very important. Because rolling strip belongs to multi-object contact engineering problem which involves coupling deformation, obviously the accuracy of disaggregate mathematical method is low. Therefore, in this paper,it is developed that multi-object, elasto-plastic and frictional contact multipole Boundary Element Method (BEM) by Fortran program. It can simulate five object synchronous contact accurately without artificial assumption.The three dimensional rolling-pressure distribution regulation of rolling strip has been obtained through this program. Through testing and calculating the load properties of bearing, the result shows that it is accordant for test and calculation. Therefore, multi-pole BEM is one of the effective numerical analytic tools of rolling contact problem, and the obtained result of rolling-pressure distribution can provide for reference value for analyzing rolling strip.

Abstract: Aiming to avoid the skidding of a moving electric pallet truck, a new anti-skid method was proposed in this paper, which changes the proportion of enduring pressure between the driving wheel and trundles of the electric pallet truck. And a hydraulic anti-skid system was built up according to this method. Based on the theoretical analysis of the hydraulic anti-skid system, simulations were carried out by using AMESim and Matlab/Simulink software, and the anti-skid experiments were implemented. The results of simulations and experiments all show that the designed hydraulic anti-skid system can prevent trucks from slipping and can realize accurate and real-time anti-skid control.

Abstract: Thermoplastic natural rubbers (TPNR) blends consist of thermoplastics, such as low density polyethylene (LDPE), alloyed with natural rubber (NR) with different thermoplastic to NR ratios. The soft grade TPNR is produced by blends with compositions richer in rubber while the harder grades can contain up to about 30% NR. This study investigate the influence of new binder system containning of TPNR on injection parameter, density of injected molded specimen and changes during solvent extraction. Results shows that TPNR plays an important role as a good binder system and shortens the solvent extraction process.

Abstract: The objective of this paper is to investigate the effect of radius of curvature on the material removal in the NC polishing of aspheric part. The models of polishing pressure and material removal rates were established based on Preston equation and Hertz theory. The material removal rates was analyzed. Experiments were carried out. Results showed that the material removal rate varies with the variations of the curvature under a constant polishing force and velocity, and the part can not be polished uniformly.

Abstract: Injection moulding is an important manufacturing method for plastic parts. There are however many moulding quality defects caused by inappropriate setting of moulding process conditions, as well as the poorly designed plastic part geometry. Often, stiffeners are used in a plastic part to increase its strength. However, if the stiffeners are not designed properly, they will introduce one or more moulding quality problems, which in turn will worsen the part strength rather than increasing it. Although there have been quite a lot of researches on optimising moulding quality, it is often difficult to minimize multiple quality defects simultaneously. In this paper, we propose to employ flow uniformity as the optimisation objective to address this problem. A number of stiffener layout designs are evaluated in terms of this objective to determine the best design, where standard deviations of filling times and pressures at the extremities of the plastic part are used to measure the uniformity of flow. A simple case study is also presented to demonstrate the applicability of the proposed methodology.

Abstract: To counter the problems associated with the conventional processes of producing implants, a new approach has been invented, which is the adaptation of the injection moulding process for manufacturing the fracture fixation plates. With this technique in place, we have now taken a step in the right direction towards rapid manufacturing of fracture fixation plates, for the first time. The fracture fixation plates produced using this technique comply with the international standards including MPIF Standard 35, ISO 5832-1 and ISO 10933. The advantages of the present invention are design flexibility, rapid manufacturing, cost effectiveness and minimal waste compared to conventional process

Abstract: In these days in foundry branch there is a rapid development of sectors of special casting technology with the aim to increase the quality and the efficiency of pressure casting production.. Internal homogeneity of pressure casting, characterized by the extent of porosity can be affected by the setup of technological parameters of pressure casting and last but not least by vacuuming the molds, that means to exhaust air and gases from the mold cavity. Contribution is specifically aimed on the analyzing the impact of degassing pressure molds on the porosity of pressure casting.