Advanced Materials Research Vol. 1035

Abstract: Hot compression tests of 20CrMnTiH steel are carried out in the strain rates range from 0.01s^-1 to 10s^-1 and in the temperature range from 973K to 1123K. The flow behaviors of 20CrMnTiH steel are described based on the analysis of true stress-true strain curves. The flow stress increases with the increasing of strain rate and the decreasing of deforming temperature. Johnson-Cook (J-C) model are used to analyze the hot deformation behaviors. In the constitutive model, material constants are determined based upon the experimental data. Genetic algorithm (GA) is proposed with the aim of optimizing the J-C model parameters. Good agreement is acquired by comparing of the experimental results with predicted results. It validates the efficiency of Johnson-Cook model in describing the material constitutive behavior.

Abstract: The new sponge material was prepared by the copolymerization of polystyrene and methacrylic acid. The polystyrene seed was prepared by two-step seed swelling polymerization. Scanning electron microscopy images showed that the sponge material were clumps with porous morphologies. The adsorption behaviour of the sponge material was analysed by detecting pefloxacin and enfloxacin in milk samples. Under the optimized conditions, good linearity was obtained in the range 0.05-10.0 μg g⁻¹, with a correlation coefficient (r²) of ≥ 0.9991. The recoveries at three spiking levels ranged from 85.6 to 106.9% with relative standard deviations (RSDs) of ≤6.6%. The sponge material could be applied to the rapid screening of Pefloxacin and enfloxacin in complicated milk-product matrices.

Abstract: The fly ash of non grade with low activity can not be directly used in the cement concrete. After a lot of tests, several kinds of fly ash grinding excitation materials were chosen to be ground together with fly ash of non-grade and low activity. The studies show that three kinds of fly ash grinding excitation materials A, B, C can not only decrease the water demand ratio but also increase the activity index of the polished ash as well. All other indexes meet the requirements of technical specification standards for fly ash gradeI. Based on the effect of excitation activity and economic benefits, the fly ash grinding material B was chosen as the main active materials for the power plant to make excitation ash,the fly ash composite materials can be widely used in cement concrete with high activity index and great benefits, and the problems for the application of the long-term piled fly ash can also be solved .

Abstract: Dralon superfine profiled acrylic interwoven with traditional spun silk .There are 9 kinds of interlaced fabric. We discussed that in same condition of finishing and fabric weave (3/1right twill),different picking shuttle between superfine profiled acrylic and spun silk have a impact on fabric performance of moisture absorption, air permeability, drape, crease recovery and warmth retention. The results showed that: fabric has better wearability when silk and acrylic picking proportion is 1:5(That is the content of acrylic is 61.16%).

Abstract: The raw materials of blended yarns are Dralon superfine profiled acrylic, spun silk, Modal and cotton. Considering the different components and proportion, 6 kinds of woven fabrics were designed to test, then put to test and analysis the date of the heat retention, hygroscopicity, permeability, wrinkle resistance and drape performance. The results showed that,40S/1 acrylic / Modal (65/35) blended yarn can improve the warm of blended-spun-yarn fabric,40S/1 spun silk / acrylic / Modal (30/40/30) blended has a good quality of wrinkle resistance and permeability.40S/1 spun silk/ acrylic / cotton (20/50/30) blended can improve the drape performance and hygroscopicity of multi-component blended-spun-yarn fabric.

Abstract: To provide the technical support for developing the highly light-proof decorative fabrics. Based on the weaving rationale of jet-weaving technology of electronic dobby jacquard, 2 type of double-layer fabrics was designed from weft arrangement ration, fabric count and yarn type, then tested on related performance including light-proofness. This dissertation combines all results of the fabric performance tests. Designed with 140 ends/cm, 72 picks/cm, weft arrangement ratio 2:1:1, and FDY silk as weft yarn, the highly light-proof drapery fabrics can achieve soft texture, lustrous surface and excellent light-proofness, which can satisfy the customers.

Abstract: According to the honeycomb hexagonal phase modulation membrane, this paper designed and prepared λ/4 electromagnetic wave absorber. Studies have shown that the honeycomb hexagonal phase modulation membrane structure can realize the absorber width. Experiments have shown that 65% of bandwidth below-10 dB was achieved under following conditions: line length a = 4 cm, line weight b = 6 mm. For line length a = 4 cm, line weight b = 6 mm, the angle characteristics of phase modulation membrane was studied. The study of angle characteristics have shown that, absorption peak moved backward with the angles increasing. This new composite materials can be used for electromagnetic interference protection for WLAN and indoor electromagnetic radiation pollution control.

Abstract: The microstructural evolution of of as-cast ZK60 magnesium alloy processed by cyclic extrusion and compression (CEC) were studied, and the effects of technical parameters on microstructural evolution were investigated. The results show that the grains of as-cast ZK60 magnesium alloy were obviously refined and uniformed by CEC, the average grain size was decreased from original 50 ~ 60 μm to about 2 μm when the extrusion ratio was 8 with 8-passes at 350°C, and the refinement effect was increased with the rising of extrusion ratio and passes. The effect of increasing passes on grain refinement was not obvious when it exceeds 8. Nevertheless, it is beneficial for the grain homogenization.

Abstract: Glass-ceramic materials of the Li₂O-ZnO-SiO₂ system, with various amounts of TiO₂ added, have been prepared. The appropriate heat treatment temperatures were selected according to the information provided by the differential thermal analysis (DTA). X-ray diffraction (XRD) analysis demonstrated that in the LZS glass-ceramics system, the main phases are Li₂ZnSiO₄, cristobalite, tridymite and quartz. The scanning electron microscopy (SEM) revealed that crystals appear as lamellar and spherical particles in the glass-ceramics samples. In addition, the average coefficient of the thermal expansion (CTE) values first decreased, then increased and finally tended to flatten. When the content of TiO₂ increased to 6%, the CTE value decreased to 9.15×10^-6/K, reached the lowest value. When the content of TiO₂ increased to 10%, the CTE value reached highest value 13.90×10^-6/K.

Abstract: A chemical inducing process was developed to prepare titania-mica pearlescent pigment. MnO₂ was used as crystal inducing promoters, a transformation between antase and rutile titania-mica pearlescent pigment was found by calcining at 800°C for 0.5 h. The mass ratio of mica to MnO₂, pH value, temperature and dripping rate of MnO₂solution and TiOSO₄was studied. The crystalline form of titania-mica pearlescent pigment was measured by XRD.