Advanced Materials Research Vols. 753-755

Abstract: For finding the influence of the original errors on the follower of the globoidal cam, vector analysis method is used. Seven original errors are defined by analyzing the machine tool and the mathematics models between the follower angular displacement errors and the original errors are established. When the original errors are designed as 0.01, the relationship curves between the largest follower angular displacement errors and the cam angles are got. The error influence coefficients between the largest follower angular displacement errors and the original errors are established on that basis. The results of this study lay the theoretical foundation of the design of the machine tool precision index system and the adjustment of the cam processing.

Abstract: The compression deformation processes of powder particles were investigated by the way of mesoscopic simulation based on finite element method of discrete body. The strain process of the particles in typical position, the deformation difference of the particles in different positions and the strain status of particles were investigated under various compacting pressure. The results show that the deformation process of the compressed powder particles consisted of three stages, which were the initial stage of small deformation, the major stage of the sharply changes of strain and the ultimate stage of strain tending to stable state. The interface friction has a significant influence on the deformation and pressed density of particles close to die wall. The density can not be increased with the increase of compacting pressure of compaction infinitely.

Abstract: In heterogeneous turbine blades, multiple materials can be synthesized to provide better properties than any single material. In this paper, a new method for turbine blade modeling toward reverse engineering, termed as multi-color distance field, is presented. In this method, the material field describing the material composition continuous or discontinuous variation is associated with the signed distance field describing the geometry model. The method allows the designers to design and optimize no only the geometry but also the material composition of an object. Moreover, both the geometry model and the material information can be easily sliced to manufacture for the object represented using the associated multi-color distance field.

Abstract: In this paper, the die-casting processing of aluminum alloy was simulated by casting simulation software. The mould filling and solidification process of aluminum alloy die-casting in different cast temperature and shot velocity were investigated. Aiming at achieving the best casting process, this research gave emphasis on analysis the influence of cast temperature and shot velocity to the process of mould filling, temperature field of casting part during filling and solidification, shrinkage and porosity. To improve the process, increase ingate area, carry on the simulation, and analyze the optimal casting parameters.

Abstract: According to the different softening mechanism, a flow stress model for magnesium alloy AZ31B is established. At the stage of dynamic recovery (DRV), the effect of work hardening (WH) and DRV on flow stress is described by dislocation evolution model. At the stage of dynamic recrystallization (DRX), the flow stress curve is obtained from Avrami equation denoting the recryatallization kinetics. Model parameter and its dependence on deformation condition are identified by the measured flow stress curve. The calculated curves agree well with the measured ones, which demonstrate the availability of the method.

Abstract: With the rotating machinery system developing toward high speed, high precision, and high reliability direction, ball bearing dynamic performance have a critical impact to dynamics characteristics of support system. Based on multibody dynamics theory and contact dynamics method,and considering the ball and ring raceway 3 d dynamic contact relationship, using ADAMS dynamics analysis software to establish the multibody dynamics model of crank slider mechanism containing ball bearing dynamic contact relationship.The simulation analysis of the dynamic performance of the ball bearing and the crank slider mechanism dynamics response, and the influence of dynamic performance for considering ball bearing rotating mechanical system dynamics analysis provides a reference method.The simulation analysts the influence of dynamic performance of the ball bearing to the crank slider mechanism dynamics response. It provides a reference method for rotating mechanical system dynamics analysis considering the dynamic performance of the ball bearing.

Abstract: In order to solve the problem of machining work-pieces with complex space curved surface, a machining system was developed, and the rotary table with two sways is the most important part. The motion rules of machining work-pieces with complex space curved surface were analyzed, and the computer simulation of WEDM five-axis linkage system was put forward. Through running the simulation programs, the whole machining process of WEDM five-axis linkage system can be directly observed, and the satisfactory simulation results can be obtained. The NC machining system with five-axis linkage by WEDM was developed, and the complex curved surface work-pieces can be machined by combining the rotary table with two sways with the WEDM-HS machine tool. The key technology problem of machining work-pieces with complex space curved surface has been fundamentally solved, and the application range of WEDM-HS machine tool is widened, which suit the specific conditions in China.

Abstract: Numerical simulation in the 200ml beverage can forming process was carried out by means of computer aided engineering. Beverage can drawing production process parameters and a forecast for the production process of all sorts of possible defects were obtained. Based on the results of the simulation, we can improve die structure and process method. Thus the development costs of die will be reduced. The manufacturing time of die will be shortened. The purpose of reducing the cost of production can be achieved ultimately.

Abstract: In this paper, we study the finite difference solutions for two new models of phase transitions driven by configurational force. These models are recently proposed by Alber and Zhu in [2]. The first model describes the diffusionless phase transitions of solid materials, e.g., Steel. The second model describes phase transitions due to interface motion by interface diffusion, e.g., Sintering. We consider both the order-parameter-conserved case and the non-conserved one, under suitable assumptions. Also we compare the results of these two models with the corresponding ones for the Allen-Cahn and Cahn-Hilliard equations. Finally, some results about tending to zero are given.

Abstract: According to the characteristic of Yuzhou Danhou mine long flame coal, the drying processes of coal was study on mixed flowing vibrating drying system. The parameters were tested during the drying process, and thermodynamic process of drying were analysed, the result show that reducing the exergy loss of hot stove is the key point to improve the efficiency of drying system.