Advanced Materials Research Vols. 335-336

Abstract: 45 steel was quenched with zero time holding at different temperatures, followed by a high temperature tempering. The influence of quenching temperature on hardness, yield strength, tensile strength and microstructure of the steels was investigated by Rockwell tester, universal testing machines and metallographic microscopy, respectively. The results show that under quenching condition of zero time holding, hardness and strength of the 45 steel increase with increasing quenching temperature and reach the maximum at 860 °C, where the content of martensite is maximum while that of ferrite is minimum in the specimen. At higher temperatures, the grains become obviously coarse, resulting in decrease of mechanical properties.

Abstract: The Internet of Things need new business mode to developing. Under the booming manufacturing industry, modern IT technology is applied in traditional mechanical processing and manufacturing industry to relieve the talents shortage, and to improve production efficiency. According to the characteristics of CNC machinery, proposed an idea that to establish a CAD/CAM integrating services platform by equipment manufacturing enterprises. By taking full advantage of technology and human resources, offer services to equipment users to meet market demand. The mode uses advanced computer network technology, providing a new business model to the development of the internet of things, also, offering a new way for the upgrading of enterprise products.

Abstract: With the rapid development of oil industry, the high strength-toughness drill pipe suited to the task of sour environment and ultra deep wells would be considered more and more important. A new drill pipe steel, which was designed with the proper decrease of C content and increase of Cr, Ni, Mo, Nb and V alloy element, was developed and studied in this study. The results showed that the yield strength of this new drill pipe steel had reached 150ksi with the impact toughness more than 150J, which can perfectly meet the “leak-before-break” crack principle. Based on the observation of optical microscopy and transmission electron microscopy, several kinds of carbide particles including (Nb, Mo, V)C with nanometer scale, were distributed in tempered sorbite matrix. The objective of this work was to study the relationship between multiple alloy-carbide precipitation and mechanical property of this drill pipe steel.

Abstract: The continues cooling transformation (CCT) of a low carbon Mn-Nb-B steel in the undeformed and deformed conditions were investigated, respectively. The CCT diagrams of the steel were constructed. The microstructures and microhardness were analysized. The results showed that the microsructures contains ferrite, pearlite, granular bainite, acicular ferrite and lath bainite depending on cooling rate; Deformation moved the CCT curve to the top left corner, increased the transformation start temperatures slightly, and promoted the formation of ferrite and pearlite. Furthmore deformation also fined the transformed microstructures.

Abstract: This paper proposes a genetic algorithm based optimization of the product and scrap inventory levels in a printing and packaging industry so as to minimize total supply chain cost. The scrap optimization procedures are in the primitive level of implementation in the industries. Determining optimal levels of scrap inventory enables the industries to attack the problem of high scrap and high inventory, thus enables the industries to make quick and sound decisions regarding the production of paper boards in a printing and packaging industry.

Abstract: CFO(Critical Flow Orifice), micro sonic nozzle, is a device in tobacco industry to give a standard gas flow rate. Adopting the blocking effect of the convergent nozzles for compressible fluid, CFO can produce an accurate flow rate in pipe line. CFO can be used in micro flow calibration such as in the measurement of the pressure drop of filter rod or draw resistance of cigarette. To study the effect of convergent shapes on the aerodynamic characteristics of CFO, the 3D numerical simulations are carried out on two kinds of CFO structure shapes with finite volume method, based on the equations of compressible gas. The adopted turbulence model is the realizable k-ε model. According to the results of simulation, using Vyshinsky curve as the convergent curve is better than to apply the cone-shaped curve with the same exit diameter of nozzle. This is difficult to be observed in the experiments. The influence of convergent shapes can provide a basis for optimization design of CFO.

Abstract: By adding the flow rate of throttle orifice to conventional stable externally pressurized gas lubrication equation, the Reynolds equation for externally pressurized dry gas seal with orifice compensation is established. The solution of the equation is studied by functional extremum algorithm and finite element method, and the computer numerical simulation is carried out in Matlab software. The effects of air supply pressure, numbers and diameter of throttle orifice, on face opening force and gas film stiffness are discussed in detail.

Abstract: The cold rolling and simulative continuous annealing experiments after rolling were carried out in the laboratory on the base of super fine grain (SFG) steel sheet. The microstructure and the second-phase particles precipitated behavior were analyzed by the technology of OM, TEM and EDX. It is found that the fined Nb(C, N) can be formed by adding micro-alloy element Nb. It is noted that the yield strength is low as well as the tensile strength is high by the PFZ which is free of precipitate called precipitated free zone on the one side of the grain boundary. Contrast to the conventional IF steel, the super fine grain steel has super fine grains and gives excellent press-formability such as low yield strength, high r-value（the plastic strain ratio）. High strength cold-rolled steel sheets (HSS) with high formability have been developed in the last decade, in which the major strengthening method was solid-solution hardening with silicon, manganese and phosphorous [1-3]. When the IF steel is strengthened with the high amount of solid-solution elements, it becomes susceptible to the secondary work embrittlement because of the lack of grain boundary strength [4-6]. In this paper, High strength cold-rolled steel sheets (HSS) with high formability have been developed for the IF steel-bases. The grain refinement and precipitation hardening are achieved by means of the fine distribution of carbide under the appropriate combination of the relatively higher carbon content near 0.0070 mass% with niobium. As the result, this type of IF-HSS has been successfully developed to reach a higher r-value as compared with the conventional IF-HSS.

Abstract: In order to improve efficiency and automation of spraying, a automatic spray lance, which was regard as an robotic arm, was studied. It could reach the desired position automatically. A study was carried out using Denavit and Hartenberg (D-H) approach to automate the four Degrees of Freedom (DOF) robotic arm. The kinematics of robotic arm was constructed us D-H coordinate frame model. And the inverse kinematics has been solved with inverse transform technique. Some motion parameters could be acquired. Simulation of the robotic arm was studied using the Robotics Toolbox which is MATLAB software. Simulations’ content included homogeneous, construction of robot object, kinematics and trajectory. The results of simulation indicated that the movement of robotic arm could satisfy the demands of four DOF. The robotic was founded able to move to the desired position by simulating. The links’ motion parameters were reasonable and it provided a new spray lance for automatic sprayer.

Abstract: With the development of NC machine tool and NC machining, the postprocessor is play a vital role increasingly, which is an interface of operations in CAM and NC machine tools transformed cutter location data into machining control data. The general kinematics model of various machine tools was constructed by analysis of machine tools configuration and NC control systems. The coordinates were of machining files calculated using Coordinate transformation matrix in the process of post-processing. Finally, a postprocessor develop by VC++ and secondary development tool in UG, through the implementation of the postprocessor and the verification with the commercial NC simulation software VERICUT as well as the machining experiment, the effectiveness of the proposed methods were demonstrated.