Advanced Materials Research Vol. 1088

Abstract: Laminated glass is widely used to enhance structural functions. The impact fracture behavior of laminated glass is more complicated than that of single glass, because of the combined influences of the large deformation and delamination strengths. In this study, the impact fracture behavior of a laminated glass plate intended for the outside surface of a modern building has been studied by numerical simulations and experiments. This fracture simulation was calculated using a Discrete Element Method (DEM) based on non-continuum mechanics. The laminated glass structures have been optimized for attaining maximum durability against impact fracture based on the response surface method. In the optimum problem, the tensile strength of the interlayer and the adhesive strength between two pieces of glass and the interlayer are taken as the design variables. From the results of the optimization, it has been observed that the laminated glass difficult to break in the case that the tensile strength was high and that the adhesive strength was a little light. The penetration performance of an optimized laminated glass plate was noticeably better in comparison with a commercial laminated glass plate.

Abstract: The present paper decribed the effects of carbocoal on temperature rising characteristic during coal pyrolysis at different temperature in microwave field. Different mixture rate of carbocoal with coal and different final temperature on coal pyrolysis tempereature rising characteristics were studied in the work. The results indicate: Coal is a poorly microwave absorbing material. Because carbocoal can be fast heated in microwave field, so it can be used as additive for coal pyrolysis. Carbocoal otained from different pyrolysis temperature have different heating rate, along with the increase of carbocoal pyrolysis temperature, carbocoal heating rate increases in microwave field. Using carbocoal as microwave absorbent for coal rapid pyrolysis in microwave field is feasible.

Abstract: Severe plastic deformation is defined as metal forming methods in which a very large strain is imposed to a bulk in order to make an ultra-fine grained metal. ECAP is one of the most effective methods in SPD. The influences of main parameters on deformation include extrusion route, extrusion pass, die corner, friction, extrusion speed and so on. In this investigation, a model of ECAP process has been developed based on FEM and effects of extrusion speed on effective strain, load and effective stress imposed in the copper road are researched. The results of simulation have shown that lower extrusion speed can lead to higher load of top die and effective stress while the effect of extrusion speed on effective strain of copper road is slight.

Abstract: The carbide cemented special drills with TiAlCrN/TiSiN coating and diamond coating respectively were selected to drilling on carbon fiber reinforced plastics (CFRP) for a contrast test in this paper. The drilling force , drilling exit surface quality and tool wear were analyzed separately to research the performance characteristics of the two kinds of special drills with different coating. The results show that: under the same cutting conditions, the thrust force of the special drill with diamond coating is smaller than that of the TiAlCrN/TiSiN coating, and the tool life is extended by 2 times at the same time. The diamond coated special drill can improve the drilling surface quality, it is more suitable for drilling CFRP.

Abstract: Using the finite element software ANSYS to establish thermal structure coupling model of copper cooling stave. Taking into account the cooling stave hot simulation of the boundary conditions, respectively to calculate the temperature distribution, thermal stress and deformation of rolled copper cooling stave and cast copper cooling stave embedded copper pipe under high temperature. The calculation results of temperature and heat stress show that the copper cooling stave could meet the requirements in the worst condition of blast furnace, and will not generate fatigue crack under high heat loading.

Abstract: According to the structure of cast copper cooling stave, two kinds of different pouring systems were designed, and the casting process numerical simulations were conducted with ProCAST software in order to project the foundry defects. Then adopting the process optimization based on the preliminary simulated results and determined the final casting technique of cast copper cooling stave. The results of trial production show that the cast copper cooling stave basically meets the requirements of technology.

Abstract: This study analyzed the bond line strength of Eucalyptus sp. specimens submitted to shear and perpendicular to grain tensile forces, depending on the wood quality machined surface. The woods plans were glued with two different polyvinyl acetate adhesives. The bonding surfaces were milling with three different feed speeds; 6.0, 11.0 and 15.0 m/min, corresponding to the feed per tooth of the cutting tool; 0.86, 1.57 and 2.14 mm, respectively. The specimen types corresponded to the standards according to ABNT NBR 7190/1997. The cutting plane considered only the geometry of milling due to the bond line joint strength. To explain the experimental results, was proposed a linear elastic model to machined wood and bond line. For the two adhesives used, the experimental results suggest that the greatest perpendicular to grain tensile strength and shear strength were obtained to bond surface machined with the intermediate feed speed namely 11 m/min, for others two feed speeds and in the shear strength case, was not observed a distinction between them, in the perpendicular to grain tensile strength, the feed speed 6.0 m/min presented a higher strength than the machined surface with 15.0 m/min. The model reproduces the behavior of the experimentally results obtained for the two tests, and so it can be readily applied as a tool for evaluate the machining feed speed and the bond line joint strength.

Abstract: This paper deals with the stress discontinuities in shear stress distribution of adhesive joints. The three-dimensional finite element analysis (FEA) software was used to model the joints and predict the shear stress distribution along the whole beam. The FEA results indicated that there are stress discontinuities existing in the shear stress distribution within adhesive layer and adherends at the lower interface and the upper interface of the boded section. The numerical values of the shear stress concentration at key locations of the joints and the stress concentration ratio are discussed.

Abstract: The effect of boundary conditions on the stress distributions in single-lap adhesively bonded cantilevered beams has been investigated using the three-dimensional linear static and non-linear quasi-static finite element method. The displacement obtained from the linear static and the non-linear quasi-static analyses are compared under the same deformation scale factor for three typical boundary conditions. The analysis results indicate that there are significant differences between the linear static and non-linear quasi-static analyses only if there are significant bending effect on the bonded section. The bigger the bending effect on the bonded section, the bigger the difference between the linear static and non-linear quasi-static analyses.

Abstract: The effect of adhesives behavior on the normal stress distributions of single-lap adhesive joints is investigated using the three-dimensional finite element technique. Numerical examples are provided to show the influence on the normal stresses of the joints using adhesives of different characteristics which encompass the entire spectrum of elastic stiffness behaviour. finite element analysis solutions of the normal stress distributions in the adhesive layer have been obtained for four typical characteristics of adhesives. The results indicate that Young’s modulus and Poisson’s ratios of adhesives strongly affect the normal stress distributions of the joints.