Applied Mechanics and Materials Vols. 101-102

Abstract: In the traditional titanium alloy processing, Titanium alloys, however, are generally machined at lower cutting efficiency due to their low cutting speed and low cutting tool durability. This paper introduces a static cooling auxiliary method of titanium alloy TC11 cutting to solve the above-mentioned problems. The static cooling cutting can solve pollution by using coolant and decrease the consumption of resources and solve disadvantages in traditional titanium alloy processing problems.

Abstract: Aiming at the slender hole of the screw motor stator which has a large lead and whose cross-section contour composed by convex and concave curve, the article proposed a processing method using finger milling cutter within a continuous inner helicoid and studied the formed theory about the movement of the tool relative to the workpiece. A new method was proposed to calculate the contour of the tool using limited point data of the contour of workpiece and the related software programs was designed. By designing and implementing of computer simulation, the correctness and feasibility of the processing technology are verified.

Abstract: A wire-saw cut KDP crystal geometrical model was founded and a mathematical model was established to calculate the grit average cut depth, based on indentation fracture mechanics theory(IFMT). The relationship between the grit cut depth and wire saw process parameter was analyzed theoretically. The research results indicate that there exists an approximate monotone increasing non-linear correlation between grit average cut depth and the ratio i value of crystal feed speed and wire speed. By increasing the wire speed and crystal feed speed accordantly, the value of i can be maintained invariable, however, this way can simultaneously bring higher machined surface quality and machining efficiency.

Abstract: The powder feeder head is studied, which is one of the key to laser cladding. In view of many coaxial nozzles that are used nowadays, we have found that while cladding is doing, most of the nozzles have poor affect on powder-gathering. So as have researched on the theoretical and experiments, we designed a new coaxial nozzle, which has a great affect on powder-gathering, and can be modular disassembled. We have researched on powder stream theoretically, shot the morphology of powder stream by using high-resolution CCD camera, and analyzed the parameters of powder stream. And this new coaxial nozzle has been used in laser cladding experiments.

Abstract: Special software for laser molten pool temperature field based on LabVIEW was developed．Thermal radiation image of laser molten pool temperature taken by CCD were processed by the special software. It was shown that the software had a visual interface and the laser molten pool temperature field could be measured at real-time and the whole system is simple and efficiency. The software is easy to operate and can measure the laser molten pool temperature field quickly and exactly.

Abstract: Based on the analysis of now available evaluation indexes to estimate the formability of T-shaped tube hydroforming, an aggregative indicator is proposed. The effect of load path on the formability of T-shaped tube is discussed by FEM simulation, and validity of the evaluation index and simulations are proved by experiment. Results show that with the broken line load path of 0-35-35-60, the value of aggregative indicator is the greatest and the formability is the best. The optional parameters are testified by experiment and the results are in agreement with the FEM simulation results.

Abstract: Over the last decade, considering the influence of the viscous free water surface, the numerical simulation of the flow around the hull is one of the focuses in ship research. Currently, the precision of numerical simulation results need to be enhanced. In this paper, Computational Fluid Dynamics (CFD) method is used, for a real high-speed ship model, to simulate the flow around the hull and to calculate the total hull resistance with FLUENT software. The Volume of Fraction (VOF) method of two-phase fluid is used to deal with the free surface tracking. The results of resistance are compared with the ship model experimental results. It is shown that the total resistance results calculated accord with the experimental results well, and the numerical method can simulate the profile of the ship wave-making.

Abstract: In this paper, five kinds of carbon steel have been processed with laser boring. By using the dual-factor experimental method without repetition, it has been studied systematically on how boring is influenced by the parameters such as carbon content, laser power and pulse width and so on. The paper analyzed the influence on the dimension, depth and coning, which offers the viable first option of the laser-parameter for millipore.

Abstract: The CBN and YG610 were used for remanufacture thermal spray coating cutting. The feed rates, in the experiment, adopt mode of creep feed. The experiment results showed that the YG610 can cut the thermal spray coating efficiently. And the surface finish qualities are all under Ra1, which can come up to the standard of common grinding. But the CBN tools will be broken in the cutting process, though it can perform well in the evenly qualitative material. By experimental investigation and analyses, it can be conclude that both the high hardness and huge impact exist in cutting process, which are main reasons which induce tools broken. So the materials of tools for cutting thermal spray coating need possess both sufficient hardness and toughness.

Abstract: Three cutting tools, YG610, Si3N4 ceramic tool and CBN were adopted for heat cutting deposited materials. The test results show that though the impacts to the tools reducing, the CBN still break seriously. The condition by Si3N4 ceramic tool is better than CBN, whose types of tool failure change from breakage to wear. The YG610 is best material for heat cutting, whose minimum VB value is only 0.3mm. In the experiment, the wear increase with the increasing of heating temperature, cutting speed, cutting depth. But it decreased with feed rate. The analysis results show that the red-hardness is most importance factor for wears of YG610.