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41.
Static stresses analysis of carbon nano-tube reinforced composite (CNTRC) cylinder made of poly-vinylidene fluoride (PVDF) is investigated in this study. Non-axisymmetric thermo-mechanical loads are applied on cylinder in presence of uniform longitudinal magnetic field and radial electric field. The surrounded elastic medium is modeled by Pasternak foundation because of its advantages to the Winkler type. Distribution of radial, circumferential and effective stresses, temperature field and electric displacements in CNTRC cylinder are determined based on Mori–Tanaka theory. The detailed parametric study is conducted, focusing on the remarkable effects of magnetic field intensity, elastic medium, angle orientation and volume fraction of carbon nano-tubes (CNTs) on distribution of effective stress. Results demonstrated that fatigue life of CNTRC cylinder will be significantly dependent on magnetic intensity, angle orientation and volume fraction of CNTs. Results of this research can be used for optimum design of thick-walled cylinders under multi-physical fields. 相似文献
42.
A metal matrix composite has been obtained by a novel synthesis route, reacting Al3Ti and graphite at 1000 °C for about 1 min after ball-milling and compaction. The resulting composite is made of an aluminium matrix reinforced by nanometer sized TiC particles (average diameter 70 nm). The average TiC/Al ratio is 34.6 wt.% (22.3 vol.%). The microstructure consists of an intimate mixture of two domains, an unreinforced domain made of the Al solid solution with a low TiC reinforcement content, and a reinforced domain. This composite exhibits uncommon mechanical properties with regard to previous micrometer sized Al–TiC composites and to its high reinforcement volume fraction, with a Young’s modulus of ∼110 GPa, an ultimate tensile strength of about 500 MPa and a maximum elongation of 6%. 相似文献
43.
The present work deals with the modelling of damage behaviour for sheet moulding compound (SMC) composite materials using a finite element analysis package. Specifically, a comparison is made between the results obtained experimentally for a three-point bending test, and those obtained from numerical simulation using a material model already implemented. The simulation has been performed for the material models available within the PAM-CRASH software. The simulation results are compared and validated with respect to experimentation. 相似文献
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To determine three‐dimensional fiber orientation states in injection‐molded short‐fiber composites, a confocal laser scanning microscope (CLSM) is used. Since the CLSM optically sections the specimen, more than two images of the cross sections on and below the surface of the composite can be obtained. Three‐dimensional fiber orientation states can be determined by using geometric parameters of fiber images obtained from two parallel cross sections. For experiments, carbon‐fiber‐reinforced polystyrene is examined by the CLSM and geometric parameters of fibers on each cross‐sectional plane are measured by an image analysis. In order to describe fiber orientation states compactly, orientation tensors are determined at different positions of the prepared specimen. Three‐dimensional orientation states are obtained without any difficulty by determining the out‐of‐plane angles utilizing fiber images on two parallel planes acquired by the CLSM. Orientation states are different at different positions and show the shell–core structure along the thickness of the specimen. Fiber orientation tensors are predicted by a numerical analysis and the numerically predicted orientation states show good agreement with measured ones. However, some differences are found at the end of cavity. They may result from the fountain flow effects, which are not considered in the numerical analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 500–509, 2003 相似文献
46.
改性双马来酰亚胺的研究 总被引:2,自引:0,他引:2
本文研究了双马来酰亚胺与烯丙基化合物形成的改性树脂体系的固化和热性能,讨论了单体配比、增韧剂、催化剂对性能的影响。 相似文献
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针对辽河油田应用泡沫夹克管道的情况,从泡沫夹克管的制作和敷设施工直到设计等环节,结合泡沫夹克管防腐保温的机理,并从理论与实践相结合角度出发,提出导致泡沫夹克管腐蚀损坏的最主要原因是管道保温层漏水,进而提出了在设计和施工过程中提高泡沫夹克管质量的措施。 相似文献
49.
1 INTRODUCTIONParticlesreinforcedtitaniumalloymatrixcomposites(TMCp)havewideapplicationfieldsfortheirattractivehighspecificstreng 相似文献
50.
采用声发射(AE)技术,通过测定AE事件数、幅度和持续时间等发射特征参数以及恒载 Felieity效应,对SiC/Al和C/Al两类束丝纤维增强铝昨合在拉伸变形过程中的损失失效特征进行了分析探讨。实验结果表明,纤维种类、界面状况对复合材料损伤过程有着显著的影响,声发射技术是表征这类复合材料损伤特征很有潜力的方法。 相似文献