Frontiers in Materials Science and Technology

Paper Title Page

Authors: Rui Xiang Bai, Hao Ran Chen, Qing Wang, Cheng Yan
Abstract: Based on the first order shear deformation plate theory, a numerical analysis model of composite laminated plates with distributed PZT actuators under thermal load was established, and the corresponding formulae of finite element method were presented considering the effect of adhesive layer between PZT actuator and plate. For a two ends simply supported plate, the thermal deformation of the plates induced by different temperatures on the upper and lower surfaces and the thermal deformation compensation for the plates using PZT actuators were studied, then the optimization of voltages applied to each actuator was discussed.
Authors: Qiang Yuan, Dong Yang Wu, Stuart Bateman, Shirley Zhiqi Shen, C. Gloria-Esparza, Kenong Xia
Abstract: The conductivity and mechanical properties of carbon black (CB) filled polyethylene (PE) composites depend on the conductive filler, molecular structure of polymer matrix, and the processing methods which are applied. CB filled high density polyethylene without and with glass fibre (GF) composites have been manufactured using single and twin screws extruder. The composite made from the single screw extruder showed a much higher conductivity than that made from twin screws extruder for CB/PE composites with and without glass fibre. The conductive paths are formed at very low CB content (1wt% CB for GF/CB/PE) when using single screw extruder to manufacture. The microstructure of these composites were analysed using SEM.
Authors: Ning Hu, Yutaka Zemba, Hisao Fukunaga
Abstract: In this paper, we have proposed a new cohesive model to stably and accurately simulate delamination propagations in composite laminates under transverse loads. In this model, we set up a pre-softening zone in front of the original softening zone. In this pre-softening zone, the initial stiffness is gradually reduced as the interface strength decreases. However, the onset displacement for starting the real softening process is not changed in this model. The fracture toughness of materials for determining the final displacement of complete decohesion is not changed too. This cohesive model is implemented in the explicit time integration scheme. A DCB problem is employed to analyze the characteristics of the present cohesive model. Moreover, an experimental example of laminates under impact loads is employed to illustrate the validity of the present method.
Authors: Meng Hou, Lin Ye
Abstract: The paper describes the manufacture of thin composite panels using high performance sheet moulding compound (SMC). Topics discussed within the paper include characterisation of curing and flow behaviour of SMC material, tooling design concept and determination of suitable processing conditions for compression moulding. A Full scale “Burst test” was carried out to evaluate the mechanical performance of SMC panels. The overall performance of the SMC panels was satisfactory with all panels failed beyond the specification value. The main failure mode was a through-thickness cracking. In addition, a geometrical non-linear numerical analysis was also carried out to investigate the stress distribution and deflection behaviour of SMC panel during “Burst testing”.
Authors: Jelena Muric-Nesic, Z. Stachurski, Paul Compston, N. Noble
Abstract: Eliminating common defects such as voids, bubbles and poor adhesion at interfaces will increase the quality of laminated sandwich composite structure. We are experimenting and analyzing the effect of mechanical vibrations applied to the curing system of composite materials production, particularly on minimizing void content. The range of frequency of vibrations covered was from 2Hz to 8kHz, for different period of vibrations. The composite laminates were made by hand lay-up using glass fibres and vinyl-ester resin, and examined under a microscope to determine types and quantity of defects. The results showed reduction in the number of bubbles (as well as in void content) at frequencies between 10Hz and 50Hz for 30 minutes of vibrations.
Authors: Monika Bauer, O. Kahle, S. Landeck, C. Uhlig, R. Wurzel
Abstract: Lightweight design, using high performance composites, which directly yields a reduced need for fuel is in the focus of new developments for traffic engineering. The increased substitution of traditional, metal based materials by fibre-reinforced composites in the aviation industry exemplifies this trend. In addition to mechanical properties, e.g. an increase in strength, that leads to direct weight savings, or improved dynamical performance, which translates into longer maintenance intervals, i.e. longer service-life. In the field of fibre-reinforced polymer matrix composites possible contributions from nanotechnology are currently reviewed. The modification of the matrix by introducing a “nanophase” has attracted most attention up-to-date. Additional approaches include modification of traditional reinforcements, as well as the development of new reinforcing materials. Desired improvements include mechanical properties, interlaminar shear strength, reinforcement in z-direction, fiber-matrix adhesion, and obtaining new functionalities. Starting from a summary of the most important effects of nano-modifiers in polymeric matrices, the presentation will review published results on the modification of thermoset matrix fiber-reinforced composites by using nanotechnology, as well as some of our own work in that field. Furthermore, applications of such modified composites in component parts are discussed.
Authors: Hai Bo Xie, Zheng Yi Jiang, Dong Bin Wei, Xiang Hua Liu, Guo Dong Wang
Abstract: Rolling temperature is an important factor affecting mechanical properties of hot rolled strip significantly. Traditional techniques cannot meet higher precision control imperatives. In the present work, a novel knowledge-based system has been developed for the temperature prediction in hot strip mills. Neural network has been used for this purpose, which is an intelligent technique that can solve nonlinear problem of temperature control by learning from the samples. Furthermore, an annealing robust learning algorithm was presented to adjust the hidden node parameters as well as the weights of the adaptive neural networks. Simulations in a multi-object mode have been carried out to verify the effectivity of new neural optimization system. Calculation results confirm the feasibility of this approach and show a good agreement with experimental values obtained from a steel plant.
Authors: H.C. Li, Zheng Yi Jiang, A. Kiet Tieu, Wei Hua Sun, Hei Jie Li, Dong Bin Wei
Abstract: The consumption of work rolls in cold strip mills is significant. One of the key issues for work rolls is the surface roughness which affects the rolling stability and surface finish of the strip. The produced strip has lower surface finish if the roll surface roughness is large. However, if the roll surface roughness is small, it is not helpful for establishing the rolling process, which will reduce the productivity. In this case, a laser treatment is employed to increase the value of roll surface roughness. In order to reduce the times of roll grinding, the cold strip mill and roll manufacturers have developed new types of rolls such as the rolls containing Ti to increase the roll wear resistance in cold strip rolling. Results show that the new 4CrTi roll has a significant advantage of preventing decrease of the roll surface roughness. The size and generation of particles during roll wear process and the effect of Ti on roll wear have been discussed.
Authors: Wei Hua Li, Xian Zhou Zhang
Abstract: This paper presents fabrication and characterizing of a new functional material, magnetorheological shear thickening fluid (MRSTF), by mixing micron-sized magnetizable particles with nano-sized silica particle based shear thickening fluid. Dynamic properties of the MRSTF were characterized by using a parallel-plate rheometer. The effects of steady-state shear rate and magnetic field on MRSTF rheological properties were addressed. The suspension shows an abrupt increase in complex viscosity beyond a critical dynamic shear rate and a magnetic field controllable characteristic, as well as reversible.
Authors: Xian Zhou Zhang, Wei Hua Li
Abstract: This paper presents the study of rheological and mechanical properties of MR elastomers fabricated using small and large particle. Analysis indicated that MR elastomers fabricated with bimodal particles at a specific particle ratio ingredient show enhanced MR effect compared with those fabricated with monoparticles. MR elastomer samples were fabricated by using small and large particles with sizes of 5m and 50m respectively. Their rheological and mechanical properties were characterized with a MR rheometer. Experimental results agree well with the analysis.

Showing 31 to 40 of 67 Paper Titles