Advanced Materials Research Vols. 102-104

Abstract: A hardware implement scheme is proposed based on digital signal processor, and the complex programmable logic device and industry standard architecture bus is proposed. The dual-port random access memory communication circuit, I/O port address decoding circuit, two axis control output circuit and position detecting circuit are developed, the main program and interrupt-serving program of digital signal processor are designed by the idea of modularization. The static accuray of the motion control card is tested via special experimental device. The present analysis show that the designed circuit is effective and the static control precision of motion control card is satisfied.

Abstract: The use of rule-based reasoning technology can realize the intelligent selection of mold standard parts when designing injection mold. In this paper, the selection experience of mold standard parts are stored to databases for scientifically choosing mold base, sprue bushings, ejector pins, and other standard parts. And through the establishment of a rule base, reasoning mechanism, standard parts library, a rule-based reasoning intelligent selection system of injection mold standard parts is proposed and details of the proposed approach are presented.

Abstract: Additive processes can be defined as layered manufacturing, based on the dispersed/accumulated principle, Layered manufacturing is directly transforming 3D CAD models to real objects, the reverse engineering of mechanism can be applied to layered manufacturing for production complex geometries for long-term consistency, and the analysis demonstrates the application of the reverse engineering fulfills the segments of design, production, inspection, test. The most notable advantage is the combination of digital technology and geometric model rebuilding technology.

Abstract: In tandem cold mill, a strip is flattened by stands of rolls to a desired thickness. In the process, there exists thickness disturbance and hardness disturbance, which will affect the export thickness of the strip. In order to solve these problems, control system adopt a new control strategy wherein a state-dependent Riccati equation is utilized. In the third part of this paper, the new technique which uses the state-dependent Riccati equation method for controlling the tandem cold rolling is tested by simulations. The results of these simulations are included in the evaluations which show successful control during the passage of the weld.

Abstract: A theoretical model of temperature for electrical discharge machining (EDM) is established. Based on finite element method, the distribution temperature fields of ZL108, YG15 and 45 carbon steel during EDM process are simulated with the aid of ANSYS software. The simulation model provides good effects on the surface quality forecast, parameter regulation and optimization in the process of EDM. Under same experimental conditions, the machining efficiencies of EDM ZL108, YG15 and 45 carbon steel are listed. The machining efficiency of EDM ZL108 or 45 carbon steel is much higher than YG15. The observations of YG15, ZL108 and 45 carbon steel surface micro-patterns after EDM are made by VHX-600 3D digital microscope. Form the experimental results, we can explain why ZL108 and 45 carbon steel are tractable metals, while YG15 is difficult-to-cut metal.

Abstract: In this paper, a new welding experiment is studied by applying an additional longitudinal electromagnetic field to CO2 welding process (abbr. LEM-CO2 welding).The characteristics of droplet transfer, macrostructure and microstructure are compared between LEM- CO2 welding and general CO2 welding on Q235 low carbon steel thick plate joint. The research results shows that, an additional longitudinal magnetic field can have a significant effect on properties of the droplet transfer in CO2 welding, the frequency and stability of the droplet transfer in LEM-CO2 welding are improved. The grains of welding seam are refined and welding joints has a higher quality. So the additional longitudinal magnetic field is a very simple and effective method to improve the properties of CO2 welding thick plate joint.

Abstract: This paper proposes a new efficient iterative algorithm which named flexible iterative algorithm (FIAL) with a general approach suitable for surface form errors prediction in peripheral milling of thin-walled workpiece. First, a FEA-Based model is presented to analyze the surface dimensional errors in peripheral milling of thin-walled workpieces. Then the FIAL is discussed in detail for the procedure of deformation prediction. From FIAL, an iterative scheme for the calculations of tool/workpiece deflections considering the former convergence cutting position are developed，in the scheme a small variable must be included in the calculation of radial cutting depth which never been considered in the literatures before.The proposed approach is validated and proved to be efficient through comparing the obtained numerical results with the test results.

Abstract: Influence of sub-temperature quenching temperature on the strength and hardness of 65Mn steel was studied by orthogonal regressive principle, and the microstructure of this steel after sub-temperature quenching was analyzed. Experimental results showed that the quenched structure of 65Mn steel is compound structure of lath martensite and ferrite banding. There is thin ferrite banding distributing in between the martensite laths when quenched at 780°C, accordingly the toughness is changed. The strength and hardness of 65Mn steel increased with the increasing of quenching temperature in the range of 760～780°C, the strength and hardness reached the maximum at 780°C.

Abstract: The melt fluidity of the two typical plastic, including polypropylene (PP) and polyethylene(PE), are studied in the different mold with the different characteristics of channel cross section and channel profile for the fluidity test of the melt. The relationship among the flow ratio, characteristics of channel cross section and channel profile are analyzed. The modified law of the flow ratio was proposed on the basis of the experiment, and discussed in detail. The results are better based on the experiment analysis, and the checking formula of the melt flow ratio could be used to check the designed mold in production.

Abstract: The strength ratio between two blanks of tailor welded blanks (TWBs) plays an important role in the formability aspect. To study the strength ratio effects on the formability of TWB is significant while more and more TWBs were applied in auto industry. The formability of TWBs square cup was analyzed by numeric simulation technology in the terms of different strength combination TWBs. The results indicate that the formality goes worse dramatically when the strength ratio bigger than 2.0 and the crack located on the higher strength blank side when the crack appeared. The results are applicable.