Advanced Materials Research Vols. 299-300

Abstract: This paper presented the experiments of Nd:YAG pulsed laser cutting of titanium alloy, super-alloy and stainless steel sheet, and investigated the influences of different laser cutting parameters on the surface quality factors focusing surface morphology. In comparison with air-, argon- and nitrogen-assisted laser cutting, argon-assisted laser cutting comes with unaffected surface quality and is suitable for laser cutting with subsequent welding requirement. With analyzing the interaction between pulses overlapping rate and energy, the results show that medium pulse overlapping rate and lower pulse rate helps to improve the surface roughness with pulsed laser cutting. And the results would be beneficial to find optimum cutting parameters for good separation surface.

Abstract: MFI-type(ZSM-5) zeolite nanocrystals with SiO₂/Al₂O₃ ratios of 100 has been synthesized through crystallization of gel in mesoporous system of carbon nanotubes(CNTS) with internal diameter of 20~30nm. Investigation by using X-ray diffraction (XRD), Fourier transform infrared (FT-IR), transmission electron microscope (TEM) and scanning electron microscope (SEM) shows that the nanocrystals possess the typical nanosized zeolites structural characteristics which is different from those of microsized zeolites. Compared with those of the corresponding sample synthesized in hydrothermal system, the bands of the nanosized sample are shifted slightly to lower or higher wavenumbers. The TEM images of the purified carbon nanotubes and nanosized ZSM-5 crystals after the removal of the carbon matrix suggest that clean and homogeneous carbon nanotubes have internal diameters of approximately 20~30 nm and the most crystal sizes are in the range 30~60nm. The SEM photograph verifies the existing of nanosized ZSM-5.

Abstract: Bionic snake mouth mechanism aims at realizing open bite and swallows movements of the snake mouth. Depending on the basis of the anatomy of snake mouth and the combination of bionics and engineering, the mechanism was made. Based on the static analysis of the mechanism, the finite element analysis was performed and the fang mechanism was optimized.

Abstract: The hoist drum was analyzed with the finite element method analysis in this article .First, some necessary simplifications of hoist drum were handled and the solid model of reel was made by using of Pro / E. According to the concrete condition, we established material properties, generated the meshing and loads applied as well as other imposed constraints on the rolls based on ANSYS, and finally the hoist drum deformation and stress was solved. By analyzing the results, strain and stress distribution rolls are obtained.

Abstract: In this paper, a milling test for aeronautic aluminum alloy 7050-T7451 was carried out and the cutting force was measured. The least square method was used to make a regression analysis on testing data and the experiential formula for milling was established. The influencing laws of cutting parameters on cutting force were educed, which can offer an important reference for optimizing cutting parameters.

Abstract: Water cavitation peening (WCP) with aeration, namely, a new ventilation nozzle with aeration is adopted to improve the process capability of WCP by increasing the impact pressure induced by the bubble collapse on the surface of components. In this study, the influence of water cavitation peening (WCP) treatment on the microstructure of spring steel SAE 1070 was investigated. The microstructural evolution in the near-surface of spring steel SAE 1070 as a function of WCP time was characterized by X-ray diffraction (XRD), optical microscopy (OM). After WCP treatment, changes in the microstructure, as well as residual stress and surface morphologies as functions of WCP time, were recorded using a novel experimental design involving an in-situ observation function. The obtained results indicated that the refinement grains were induced by WCP in the strengthening layer. A stable compressive residual stress layer was found in the near-surface of the investigated spring steel SAE 1070.

Abstract: In this paper, CAD technology and the network technology were unified, which used ASP technology to construct the different network coordination platform. The platform implemented air-hydraulic intensifier coordination design based on the network. Air-hydraulic intensifier design system realization based on the network and the key technology were described.

Abstract: Problems to evacuate chips will arise from manufacturing deep holes, especially for small diameters. Such problems induce frequent tool breakage and poor surface quality. The vibratory drilling enables the chip to be split into small elements thanks to the axial vibrations of the drill, self-maintained by the cutting energy. This research aims to improve breaking chip concerning high temperature alloy by vibraiont drilling as well as to establish a drilling technology. The development of breaking chip technology was presented. By the aid of the self-made vibrating drilling table, the axial vibration drilling was experimented on high temperature alloy with different parameter of vibration drilling. The breaking chip effect of vibration cutting was studied, and the axial drilling force and torque of vibration drilling were analyzed. The relation of each parameter and its effect on machining process was theoretically discussed. The experiment results show that vibration drilling is in favor of breaking chip, making the volume of chip small, and removing chips fluently, and the change of drilling force is relatively steady with some drilling parameters.

Abstract: With the advantages such as light weight, high structure intensity and good rigidity, integral panel skins have been widely applied in aerospace industry. The forming process of mechanical milling-filling auxiliary roll bending and the incremental bending of integral panel skins were proposed based on the finite element method and the experiments technique. The research shows that the shapes of panel skins were binded by the ribs plastic deformation. The roll bending was suitable to the panel skins with the low ribs or the simple structure. The incremental forming was suitable to the panel skins with the high ribs or the involutes structure.

Abstract: In the present work, minimum quantity cutting fluid (MQCF) technology was developed and applied for enhancing the machining performance by maintaining eco-friendly conditions. Machining experiments were carried on Al alloy/SiC metal matrix composite using cemented carbide tool with both MQCF and flood cooling. MQCF was effective in bringing down the forces, surface roughness, flank wear by ~17 %, ~5 %, ~12.5 % respectively compared to flood cooling. In MQCF, the consumption of cutting fluid is extremely low (10ml/min) compared to flood cooling (~ 400-600 ml/min). So, emission produced in MQCF are very less, which is eco-friendly.