Papers by Keyword: Capillary Rheometer

Abstract: The ABS/PC alloy was prepared, and the extrusion characteristics of the alloy melt was studied by a constant speed Double-capillary rheometer. The micromorphology of the blend was characterized by SEM, and extrusion processing property was also analyzed. The results show that, the ABS/PC alloy with the optimum processability properties can be obtained when the ratio of ABS to PC is 90/10, and mechanical properties of the alloy can meet the requirement of ship's magnetic compass cover. Morover, the processability properties of the alloy are sharply declined with the higher PC ratio in ABS/PC.

Abstract: Rheological studies of polymers are of great importance in optimizing the processing conditions and in designing processing equipments like injection molding machines, extruders, and dies required for various products. Melt rheological studies give us valuable viscosity data that will be helpful in optimizing the processing conditions. Parameters like melt viscosity as a function of shear rate or shear stress and temperature have become more and more important. Previous study indicated that the flow behaviour of the compound depends on the filler loading. Lesser elastic torque was found with compound containing lower filler content as compared to higher filler content. In this work, effect of dual filler, based on Carbon Black / Silica filled Epoxidised Natural Rubber (ENR) compound was investigated. A total of 80phr of filler content based on passenger tyre tread formulation was used in the experiment. The compounds were prepared by melt mixing in tangential type of an internal mixer. The rheological and the processability properties of the compounds were determined using three different testing instruments namely Capillary Rheometer, Mooney viscometer and Rubber Process Analyzer (RPA). A variation of shear rates (ranging from low to high) was performed, in order to better reflect the actual processing condition in rubber manufacturing. It was found that ENR mix with ratio silica to carbon black 70:10 exhibited the best flow behaviour and processability properties as compared to control and other mixes.

Abstract: Current trend for manufacturers associated to MIM industry try to enhance the feedstock in term of its characteristics, since it is the most crucial part of the MIM process. This paper covered the characterization and rheological studies on a ready-made feedstock of stainless steel 316L which is vital to determine the availability and suit the needs of many advanced applications. There are three different experiments involved which are Scanning Electron Microscope (SEM), Differential Scanning Calorimeter (DSC), Thermogravimetric (TGA) and Capillary Rheometer. Observation through SEM gives an insight of the bonding microstructure matrices of the feedstock and also determines the homogeneity of the feedstock. DSC testing defines the melting temperature of the 3 binders used which are 62.07°C for surfactant, 178.72°C for filler and 236.61°C for backbone binder. From TGA result, it showed that the total weight loss of feedstock was 39%. Throughout the capillary rheometer testing, the feedstocks viscosity was decreasing as the shear rate increasing. The feedstock exhibits pseudoplastic behaviour since its flow behaviour index was less than 1. It is founded that at the temperature of 190°C, the feedstock exhibits the best characteristics for injection.

Abstract: Datas which are ABS and aluminum powder blends shear rate and shear viscosity have been tested by capillary rheometer.Fitting parameters of Cross-WLF viscosity model and using the material parameters to establish the appropriate database which is in CAE software.At the same time the database is used to established for studying the warpage of plastic parts,to compare the account of warpage of the actual injection,the warping deformation obtained results of two methods are very similar.Demonstrate the effective of using the database established in CAE analysis.

Abstract: The extruded poly ether ether ketone (PEEK) and glass fibre were used to obtain the co-woven hybrid fibre fabrics and converted into composites using compression moulding technique. The effect of shear stress and shear rate on the shear viscosity of PEEK was investigated to optimise the process conditions for converting hybrid fabrics into composites. The mechanical properties such as flexural strength and inter laminar shear strength (ILSS) as a function of number of layers of fabric have been evaluated. Low velocity (2.1 m/s) repeated drop weight impact tests were carried out on the fabricated composites at 5 and 10 J incident energy. Dielectric properties as a function of temperature and frequency have been carried out. Flammability behaviour of composites has been carried out using cone calorimeter. The data generated shows that glass-PEEK based composites are excellent potential materials for advanced structural composites.

Abstract: The kneading process and formulations of feedstock obviously affect the quality of MIM products. In the present work, the rheological behaviour of the composite MIM feedstock, metal matrix (Cu) with few additions of ceramic powders (Al2O3), was measured by a selfdesigned/ manufactured simple capillary rheometer. Experimental results show that the distribution between powders and binder is more uniformly when blending time increased. Though high powder loading will increase the feedstock viscosity, the fluidity reveals relatively stable through the load curves of extrusion. Besides, the temperature-dependence of viscosity of the feedstock approximately follows an Arrehnius equation. Basing on Taguchi’s method, the kneading optimization conditions and the rheological model of the feedstock were established, respectively.

Abstract: The flow of a suspension system with glass microspheres in polymer EVA (Ethylene Vinyl Acetate) melts system was studied in a capillary rheometer. The slip velocity was determined by Mooney technique. A modified slip law describing the slip velocity as a function of the wall shear stress and particle concentration was proposed and employed to describe the flow behavior of the suspension system.