Papers by Keyword: Cure

Abstract: In this study, graphene nanoplatelets C750 (GnPs-C750) was introduced to silica-filled natural rubber composites (NR/SiO₂/GnPs) by simple latex mixing process and coagulation following conventional vulcanization process to investigate the outstanding properties compared to individuals. The SiO₂ and GnPs contents were fixed at 40 and 2 parts per hundred of rubber (phr), respectively. The results showed that in the presence of GnPs in SiO₂-filled natural rubber composites, the thermal stability of the composite was improved. Meanwhile, the rheological properties including minimum torque and maximum torque were increased and cure characteristics including scorch time and optimum cure time were decreased related to cure rate index was greater than SiO₂ individual. The influence of GnPs on the mechanical properties was investigated. The results showed that it was not significantly changed in mechanical properties.

Abstract: Fast curing of carbon fiber reinforced plastics (CFRPs) is limited by the degradation of the resin under high temperatures and by the development of internal strains. The authors counter these problems by adding nanoparticles to the matrix of CFRPs. In the presented work various volume fractions of nanosized aluminum oxide particles are integrated into the epoxy resin RTM6. To demonstrate the increased heat flow within the CFRP component, thermal conductivity tests are presented. Results show increasing values as the filler content is raised.With increasing filler content the reaction speed is also accelerated. This effect is analyzed by differential scanning calorimetry. It is shown that the particle surface has a catalytic effect on the curing of the epoxy resin. The results of the author also show that the added nanoparticles not only change the material composition, but also modify the network of the epoxy resin. In a series of experiments it is demonstrated how nanoparticles decrease the chemical shrinkage. The results show a reduction of the shrinkage higher than the volume fraction of the nanoparticles, which can be explained by the formation of interphases. Thermal mechanical analysis also confirms a decreased thermal shrinkage due to the integration of nanoparticles. Finally, the inspection of L-shaped CFRPs samples with different filler contents show the ability of nanofillers to decrease the spring-in.In summary, the integration of aluminum oxide decreases the thermal as well as the chemical shrinkage, increases the thermal conductivity and accelerates the chemical reaction.Overall, these changes in curing behavior lead to an increased dimensional stability of the CFRPs. Thus, nanoparticles may be one way of overcoming the disadvantages of fast curing cycles.

Abstract: The use of recycled natural latex rubber glove (NRL-G) as a reinforced material filled acrylonitrile butadiene rubber (NBR) was studied. The compounds of different NRL-G loading (0, 10, 20 and 30 phr) were prepared by using two roll mills at room temperature. Two different size ranges of NRL-G such as 300μm-700μm (fine) and 2cm-4cm (coarser) were used. The properties such as cure characteristics, tensile and physical properties were determined. The NBR/NRL-G compound with the fine size of NRL-G exhibits overall good cure characteristics and physical properties compared with coarser size. The addition of the of 20 phr content NRL-G (fine) contributed to the optimum tensile properties than coarser size.

Abstract: This paper analyzed the employees' MMPI Psychological data of a company. Aiming at the problem that traditional K-Means algorithm is sensitive to the initial clustering center, this paper used hierarchical clustering algorithm CURE to mitigate the problem. Finally using CUDA technology clustered several times, so as to improve the execution efficiency of the algorithm. Through experimental verification, the improved K-Means algorithm behaved well in both execution efficiency and clustering results.

Abstract: There is a large widespread cavitation turbine components. By using HVOF Stellite alloy coating technology, brushing epoxy technology, epoxy-coated steel wire technology, brazed carbide block technology, repeated welding technology integrated control over the water turbine components cavitation,effectively prevent the turbine parts water cavitation in running condition, improve the reliability of hydroelectric equipment..

Abstract: It is difficult to control quality for precast concrete girders in curing, so we set up the curing system of precast concrete girders with computer networks, automatic control of drip irrigation technology, database technology and two-dimensional code technology, With which we can control concrete girders curing continuously. Achieve well curing results, and storage the precast girders curing process temperature and humidity data, provide the data basis for quality assessment and acceptance of post-concrete structure.

Abstract: Modification of pine woods which impregnated with formaldehyde-urea resin and subsequently cured by electron-beam (EB) radiation was studied. The results showed that the impregnated wood samples can easily cured by EB radiation under dose of 40~60kGy in air. And the water resistance and tensile strength of the wood samples were both improved significantly with proper treatments of impregnation and EB radiation curing.

Abstract: Recently, aromatic oil (AO) is one of the substances that is typically used as a processing aid especially for high filler loadings in formulating rubber compound. Aromatic oil has disadvantages in that, it is hazardous to environment, toxic and has been labeled as carcinogenic. In this research, an epoxidised oil (EO) and aromatic oil were used to investigate the effect incorporation of oil onto the SBR/NR natural rubber vulcanizates (NR). From the result obtained, EO showed shorter cure time and scorch time as the oil loading were increased up to 20 pphr of EO. Physical properties such as hardness and rebound resilience of NR/EO vulcanisate were also investigated upon exposure to different humidity level in humidity chamber. At room temperature, the hardness of EO loading onto the SBR/NR vulcanisate is lower than AO loadings. Hardness was slightly decreased with increasing rate of humidity. There is great difference in hardness and rebound resilience values between AO and EO. Both hardness and rebound resilience were not affected by humidity. This implies the existence of good filler interaction with EO and rubber which do not impart changes in the hardness and resilience properties of rubber compound. Epoxidised oil has great promising potential to replace the carcinogenic aromatic oil as it has good overall performance and renewable in nature .

Abstract: During the cure process of fiber reinforced resin matrix composites, the residual stress and deformation can be generated. The cure-dependent elastic model, which is the earliest constructed and the simplified form of the viscoelastic model, is most universally applied to the finite element analysis on the cure-induced deformation. However, stress relaxation and creep are the unique properties of resin matrix composites, which can affect the residual stress and deformation in some degrees. In this study, both the elastic model and the viscoelastic model were used to predict the residual stress and deformation of fiber composite laminates by means of the finite element method, and then a comparison between them was made. The results show that the difference between them decreases with the increase of fiber volume fraction or the decrease of resin curing shrinkage.

Abstract: Mix design of the steel fiber reinforced concrete was analyzed based on the engineering conditions. It was indicated by comparing with the strength values of steel fiber reinforced concrete (CF40) and ordinary concrete (C40) that the tensile strength of the steel fiber reinforced concrete increased about 70%, the compressive strength increased about 10%, the initial cracking strength increased about 150%.The reasonable construction technologies were used in mixing, transportation, pouring, vibrating and curing of the steel fiber reinforced concrete in order to ensure quality of the construction.