Advanced Materials Research Vols. 129-131

Abstract: For a new type of bevel gear—logarithmic spiral bevel gear, establish its tooth direction curves and the mathematical model of tooth surface equation. With CAD software platform which can intuitive understanding of complex curves and combined with conical logarithmic spiral parameter equation build the logarithmic spiral on cone surface. Then array logarithmic spiral to make them evenly distributed in the cone surface, without any interference and to meet the strength distribution on both ends of circular truncated cone equally. Use two logarithmic spirals from different starpoint as tooth direction curves of lift and right tooth surface. Finally, use space geometric knowledge to build tooth surface equation by tooth direction curves and tooth profile curves.

Abstract: Hybrid carbon membranes were prepared by adopting phenolic resin (PR) and poly(vinyl alcohol) (PVA) blended polymer as precursor, and zeolite 5A as additives through pyrolysis. Thermogravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscope and gas permeation technique were used to characterize the precursor and carbon membranes. The results have shown that the thermal stability of hybrid polymeric membranes is enhanced by incorporating with 5A and defect-free hybrid carbon membranes were successfully prepared. The H2 permeability of 2125.40 Barrer and the H2/N2 selectivity of 55.9 are achieved when hybrid carbon membranes were fabricated at 700 oC.

Abstract: According to the structural features of the supporting part, the manufacturing process plan of it is made and the fixtures are designed. The process parameters are optimized by the means of setting up multi-objective function that cover productivity, cost of production, processing efficiency; The NC Programs of supporting part are drawn with UG CAM and the machining tool-path is optimized through machining simulation.

Abstract: A novel hyperbranched polyurethane (HBPU) finishing agent was prepared by graft copolymerization of hyperbranched poly (amine-ester) polyols (HPAE) and the isocyanate-terminated polyurethane prepolymer(PPU). The PPU was synthesized by step polymerization of isophorone diisocyanate (IPDI) with polyethylene glycol (PEG) and dibutyltin dilaurate (DBTDL) as catalyst. The FT-IR spectroscopy was used for the structural characterization. The thermal properties of HBPU were characterized by TGA. Microphase separation of HBPU film surface was studied by tapping-mode atomic force microscopy (AFM). Moreover, in contrast to 200-UT, the physical and mechanical properties of HBPU as finishing agent were investigated: curing time was decreased by 26.15% and the water vapor permeability was increased by 9.04%.

Abstract: Treating high speed milling theory as the guidance, this paper researched high speed milling process of bracket part based on UG NX. Combined with the structural features of bracket part, three dimensional model is built by UG NX CAD and machining processes are worked out after analysis. UG CAM module was applied to fabricate tool paths. At last, finite element analysis method is introduced to study the processing deformation by UG NX NASTRAN module, based on which measures to restrain processing deformations is advanced and processing sequences are optimized.

Abstract: The job shop scheduling problem (JSSP) is one of the most difficult problems, as it is classified as an NP-complete one. Particle Swarm Optimization, a nature-inspired evolutionary algorithm, has been successful in solving a wide range of real-value optimization problems. However, little attempts have been made to extend it to discrete problems. In this paper, a new particle swarm optimization method based on the clonal selection algorithm is proposed to avoid premature convergence and guarantee the diversity of the population. Experimental results indicate that the proposed algorithm is highly competitive, being able to produce better solutions than GA and CLONALG in several cases, and is a viable alternative for solving efficiently job shop scheduling problem.

Abstract: This paper takes a kind of 3-UPS Parallel Machine Tool (PMT) as the objective of research. First, the kinematic analysis is carried out to the machine and the kinematics equation is obtained. Then, the mathematical model on tool posture error of this machine is established in considering the joint gap based on the kinematics equation. According to the mathematical model expression, the posture error of tool tip point can be calculated when the specific values to the length error of the driving rod and the position error of the joint point are known. The establishment of error model has important theoretical significance to the design as well as the error analysis and compensation of this Parallel Machine Tool.

Abstract: In order to avoid using P2O5 as phosphorylation reagent in phosphorylation reaction, an amphoteric phosphate ester surfactant was synthesized by using polyphosphate acid as phosphorylation reagent. The phosphorylation reaction studies confirmed the best condition was molar ratio of hydroxyl and P2O5 of 3.0:1.0, reaction temperature of 80°C and reaction time of 5.5h. The content of monoalkyl phosphate (MAP) and the conversion rate reached to 89.3% and 97.2%, respectively. The production of MAP product was increased by 15% than that of obtained by P2O5 as phosphorylation reagent. The structure of the phosphate ester surfactant was characterized by FTIR. The surface tension of phosphate ester surfactant was better than that of dodecyl trimethyl ammonium bromide and sodium dodecyl sulfate. The application results indicated the leather oiled by the amphoteric phosphate surfactant was softer and than that treated by L-3 fatliquor.

Abstract: The blank of heavy pressure vessel is forged directly, so its machined surface is very terrible. Because of its very large size and weight, it costs very much time and expenses cost, lots of tools and activity float to turn it during the period of rough machining. This paper describes the machining characteristic of the machining difficult points of heavy pressure vessel in China. Through analyzing the processing difficulties and utilizing the methods of experimentation and manufacture, it discussed on the choice of cutting parameters, tool structure and the optimization of tool material and so on. Then the effective measures of rough machining efficiency were constituted. Last, the processing plan which is summarized turns into the guidance of the heavy pressure vessel in actual production period.

Abstract: PET/PTT bicomponent filament composed of PTT and PET arranged side-by-side often manifest high curliness after being thermally stimulated at different temperature. In this article, we report an investigation of the effect of thermal stimuli on the performances of PET/PTT bicomponent filament under various temperatures. Both the original and the thermally stimulated ones were characterized by mechanical, thermal, thermo-mechanical and optical methods. The changes of other relevant properties were also discussed.