Applied Mechanics and Materials Vols. 275-277

Abstract: Moldflow software is used to analyze the warping of the PMMA sheet in this article. It is shown that density of bar-defects, cross-section shape of bar-defects and sectional dimension of bar defects influence the warping in different level. The relationship of bar-defects and warping is amply analyzed. As a result, it is found that cross-section shape of bar-defects and sectional dimension of bar defects have more influence to warping, especially in the vertical direction of the surface. At last, some feasible method is put forward to decrease the warping.

Abstract: In order to meet the industrial demands for large-sized bulk ultrafine-grained materials, which were prepared by severe plastic deformation, the law curves of equivalent strain, equivalent stress and load of different-sized extrusions had been gotten by the finite element simulation of ECAP. The extrusion size has little effect on the values and distribution law of equivalent strain as well as the values of equivalent stress. With the increase of extrusion size, the distribution uniformity of equivalent stress decreases, and the extrusion load increases. Although the ECAP of the large-sized extrusions improve the requirements of mold and equipment, the chunk of evenly ultrafine-grained materials can be obtained by multiple passes.

Abstract: The effect of isothermal forging on microstructure and mechanical properties of Ti-44Al-4Nb-4Zr-0.2Si-1B alloys were investigated by means of BSE, TEM, tensile and the high cycle fatigue test at room temperature. The results showed that the lamellar thickness and volume fraction of equiaxed γ phases and B2+ω phases decreased, the grain size and volume fraction of lamellar α2+γ colonies was raised after isothermal forging. The lamellar was bending. The tensile strength and yield strength was increased by 80MPa although the total elongation hardly changed. The fatigue limit was increased by 230MPa. The effect of boride, lamellar thickness and B2+ω phases on the mechanical properties were studied.

Abstract: Polyester fabric was finished by water-absorbent and quick-dry agent Casofter-252 and moisture management agent Hipom-790 for improving its moisture management property. The quality of moisture absorption finishing of the polyester fabric was detected in terms of wicking height and fast drying time. And the influence of agent concentration, pH, and curing temperature and time on moisture management property was studied in order to obtain the optimum process condition. The best choice for Casofter-252 was agent concentration 20g/L, pH 3, curing temperature 135 oC, curing time 120s, and the optimum finishing condition for Hipom-790 was as follows: agent concentration 30g/L, pH 5, curing at 115 oC for 140 s. The finished polyester fabric under the optimum condition showed much better air permeability. The tensile strength of the fabric increased after moisture finishing with Hipom-790 while it decreased for Casofter-252 used as a finishing agent.

Abstract: Regular micro-apparatus which covered with periodic nano-hole, nano-ridge and ripple structures on silicon bulk were formed by laser micro-machining with tightly focused beam of the femtosecond laser with wavelength of 800 nm, repetition rate of 1 kHz and the pulse length of 130 fs in air. The periodic nano-hole structures which focus with a 20× focusing objective lens (NA = 0.4) is reported. Investigating the relationship between the width of structures and the speed of processing.

Abstract: Very important cutting tool property is its durability. Durability of cutting tool defines lifetime of this cutting tool and it determines its suitability for select technological operation. Technical science defines a lot of different factors, that they may be cause of shorter cutting tool lifetime. For increase cutting tool durability is necessary maximally possible elimination of these factors. Determination of cutting tool durability is very important, because provides comprehensive information how to determine appropriate technological conditions for selected cutting tool. In engineering is for determination of cutting tools durability used T-vc dependence. The article describes process how to create durability dependence for cutting tools made of cutting ceramic by means of T-vc dependence in machining process of C60.

Abstract: Tube hydroforming (THF) technology is an efficient and economical technology of tube plastic forming process. Constitutive equation is the foundation of tubular material selection and finite element analysis, which also provides a way of mathematical modeling in reflection of material macroscopic properties. In this paper, the importance of constitutive equation to THF process is briefly discussed; the present establishment methods of constitutive equation are classified; the advantages and disadvantages of these methods are clarified; the development trend in establishment methods is summarized.

Abstract: Veneer horizontal consolidation machine new technology mainly adopts machine vision of some control detection method based on machine vision I tried to the detection device used in the production process of veneer joining together. The basic principle of this new technology is in veneer test, using image sensors to collect veneer size and defect status, again through the system of image sensor OCR size, shape, veneer characteristics, pixel parameters, such as calculated by measuring, discriminate veneer appearance of the manifestation of the specimen of veneer characteristics of processing judgments and will test results signal to PLC control system, by the system control device of crack and holes etc do not accord with the requirement of veneer for cutting, finally complete joining together.

Abstract: Electric arc furnace (EAF) slag is the byproduct of electric arc furnace in the process of metallurgy. In this paper, a recovering iron process combined with an activating residual slag process for EAF slag has been put forward. Researches show that increasing fineness of EAF slag is adverse to recover iron from the slag and 21.27% of the EAF slag could be separated as recovered iron concentrate with grade of 64.34%. The residual slag after magnetic separation process could be activated through mixing activating agent. Hemihydrates gypsum was the best activating agent to improve reactivity of the residual slag, which could meet the requirement of the first grade of steel slag powder in national standard. Then residual slag cements had been successfully prepared with 30% of activated residual slag and a 28-day compressive strength of 44.46MPa.

Abstract: Dynamic mold temperature injection technology can be used to eliminate many surface defects such as weldline, flow mark that usually appear on the polymer parts. In this paper, fiber reinforced ABS material is employed in order to study the influence of mold temperature on tensile strength and fiber orientation properties in dynamic mold temperature injection technology. By studying the standard specimens obtained in our laboratory, the relationship between the tensile strength and the dynamic mold temperature was demonstrated. The influence of the fiber orientation on the tensile strength was also investigated. Experiment results showed that the fiber orientation in different places of the specimen had a great effect on its tensile strength. Studies presented in this paper are of great help to promote the application of the technology in fiber reinforced polymer material.