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Ashwini Kumar Dash 《纺织学会志》2018,109(7):952-960
3D fabrics as reinforcement can be manipulated in discrete numbers of weave designs in order to earn maximum gain so that the desired mechanical properties of the composites can be achieved eventually for particular end use. Thus interest has been focused to investigate tensile, impact and knife penetration properties of 3D orthogonal and interlock structures of different weave designs by varying their binder interlacement patterns keeping stuffer binder ratio constant. The tensile properties were effectively influenced by the linear densities as well as crimp of load bearing tows, which were determined by the weave design of the fabric. The compact structure generated from regular weave pattern in case of 1 × 1 plain orthogonal and 1 × 1 plain interlock fabrics exhibited better impact energy absorption. Owing to higher values of peak energy in the knife penetration test, it is revealed that more is the number of fibres in the in-plane direction better is the protection. 相似文献
3.
Apurv Dash Jürgen Malzbender Robert Vaßen Olivier Guillon Jesus Gonzalez-Julian 《Journal of the American Ceramic Society》2020,103(12):7072-7081
The compressive creep of silicon carbide fiber reinforced Ti3SiC2 MAX phase with both fine and coarse microstructure was investigated in the temperature range of 1000-1300°C. Comparison of only steady-state creep was done to understand the response of fabricated composite materials toward creep deformation. It was demonstrated that the fibers are more effective in reducing the creep rates for the coarse microstructure by an increase in activation energy compared to the variant with a finer microstructure, being partly a result of the enhanced creep rates for the microstructure with larger grain size. Grain boundary sliding along with fiber fracture appears to be the main creep mechanism for most of the tested temperature range. However, there are indications for a changed creep mechanism for the fine microstructure for the lowest testing temperature. Local pores are formed to accommodate differences in strain related to creeping matrix and predominantly elastically deformed fibers during creep. Microstructural analysis was done on the material before and after creep to understand the deformation mechanics. 相似文献
4.
Neural Computing and Applications - In this work, empirical mode decomposition (EMD)-based optimized added kernel least square support vector machine (OAKLSSVM) hybridized model is proposed for... 相似文献
5.
In this paper, analytical estimation of energy dissipations, such as viscous, Joulian, and Darcy dissipation of viscoelastic flow phenomena over a deformable surface has been presented. This supplement to the study of many transport processes, which occur in nature, and various experimental setups that are driven or modified by the composition of the various flow characteristics and material or phase constitution. These processes are very important and have received considerable attention in the literature. The estimation of dissipative energy in the process of transport energy is an important phenomenon to investigate. The present analysis is carried out on steady MHD viscoelastic liquid due to deformable domains. Moreover, the impact of internal heat sources and prescribed thermal conditions, such as surface temperature and heat flux, are carefully studied. Analytical solutions to governing equations are obtained with the help of Kummer's function. The solutions are presented graphically as well as in tables to estimate the energy losses and their effects on transport processes, which serve as the salient features of the current analysis. The outcomes serve as a guideline due to the process of transport properties as per the design requirements. Looking into the current scenario, dissipative heat energies have several applications in industries and technological processes, such as electric heaters, fuses, food processing, and several others. 相似文献
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Ashwini Kumar Dash 《纺织学会志》2019,110(4):614-624
Using weaving technology, possible manipulations can be done so as to derive maximum advantage from the reinforcements towards desired mechanical properties of the composites. Thus with different sets of weaving parameters and tow linear densities, an attempt has been made to investigate tensile, impact and knife penetration performance of different stuffer layers and fibre volume fractions of 3D orthogonal and interlock E-glass fabrics as reinforcements for composite applications. The tensile properties were effectively influenced by warp tow crimp%, number of stuffer tows per unit width of the fabric and fabric assistance. The tow linear density, fabric sett and the number of cross over points play a determining role towards impact energy absorption capacity. The fabric sett along with tow linear densities also play a vital role towards peak energy during knife penetration test. The number of cross over points were found to be least important in the knife penetration results analysis. 相似文献
8.
An analysis is carried out for the flow of an unsteady electrically conducting liquid film on a horizontal stretching surface embedded with porous medium. In addition, a uniform heat source is taken care of in the present problem to model the governing equations of momentum and thermal energy to enhance the thermal properties of the considered fluid. Similarity variable as well as transformations are used to transform these equations into nondimensional. Solutions of these transformed ordinary differential equations are obtained using approximate analytical method, such as differential transformation method, and their refinement is verified by Pade approximant. The methodology of the analytical approach is presented clearly. Further, for validation, the numerical solutions are obtained and compared with the present analytical solution. The characteristics of the exhibiting parameters are shown via graphs and then discussed. 相似文献
9.
Meticulous analysis and consequences of microstructure changes on melt rheology and dynamic viscoelasticity of thermoplastic vulcanizates upon reprocessing 下载免费PDF全文
Pranab Dey Kinsuk Naskar Golok B. Nando Biswaranjan Dash Sujith Nair G. Unnikrishnan 《应用聚合物科学杂志》2014,131(23)
Thermoplastic vulcanizates (TPVs), which are a special class of elastomer alloy, prepared by dynamic vulcanization possess unique morphology of finely dispersed micron‐size cross‐linked elastomeric particles in a continuous thermoplastic matrix. The present study investigates the microstructure formation of elastomeric phase and its associated morphological changes during reprocessing of TPVs based on poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] triblock co‐polymer (S‐EB‐S) and solution polymerized styrene butadiene elastomer (S‐SBR) by scanning electron microscopy and atomic force microscopy. Semi‐efficient and efficient sulfur‐based curing systems have been adopted to cure the elastomeric phase and a comparative study has been made to demonstrate and explain the effect of reprocessing on the melt rheology and dynamic viscoelasticity of the TPVs. The present work also provides a better insight and guidance to control the microstructure of the cross‐linked elastomeric phase to prepare selectively co‐continuous or dispersed phase morphology. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41182. 相似文献
10.
Multimedia Tools and Applications - Visual object tracking is a key component in many computer vision applications. In real time visual tracking, abrupt changes in speed and direction of the object... 相似文献