Zhang W.,Tsinghua University |
Fang J.-R.,FAW Foundry Co. |
Xiong S.-M.,Tsinghua University
After a detailed comparison of the mold filling simulation results of three different runner systems in the die design of a seven-gear auto transmission case casting, the optimal scheme of the runner system was obtained. Through the evaluation of the solidification simulation results on locations of hot spots and shrinkage porosities, the cooling design for the die was determined. The optimal die design of the casting was successfully used in practical application and the results for air-leakage test and the appearance observation of the castings show that numerical simulation could be used as a tool for the die design of large and complex die design and this optimal die design of the seven-gear auto transmission case could be used as a reference for the die design of similar products. Source
Wu G.-H.,MAGMA Engineering Suzhou Co. |
Lu B.-S.,FAW Foundry Co.
As casting geometries become more and more challenging in their designs, the demand for intricate and high quality sand cores will also continue to increase. New modules MAGMAcore+mold have been added to MAGMAsoft, which enable its use more comprehensive and accurate. In this paper, the cylinder body core as an example, the physical modeling and simulation application of core shooting and binder hardening are described, the simulation result and practice is matched. Source
Xu X.-Y.,FAW Foundry Co.
Basing on casting process, the characteristics of production operations and limitation of manual cost accounting, the importance and the overall framework of cost accounting system were elaborated. Detailed cost accounting and the level of cost center in the overall framework, and costs control and input-output control in the cost flow were presented. The role and the actual results of the cost accounting system in our plant were explained. The cost accounting system improves the level of cost control and provides the reliable data for effective decision-making of cost and price. Source
Jiang W.,Jilin University |
Cao Z.,Jilin University |
Sun X.,Jilin University |
Liu H.,FAW Foundry Co.
Microscopy and Microanalysis
High-pressure die-casting (HPDC) AZ91 tensile specimens were used to investigate characteristics of gas pores and their effects on mechanical properties of HPDC AZ91 magnesium (Mg) alloy. Combining the stereoscopic morphology of gas pores obtained from a three-dimensional (3D) reconstruction technique with the experimental data from uniaxial tensile testing, we worked on finite element simulation to find the relationship between gas pores and the mechanical properties of HPDC AZ91 Mg alloy. Results indicate that the 2D metallography images have one-sidedness. Moreover, gas pores >100 µm in the center region have a remarkable negative influence on the ultimate tensile strength (UTS) and elongation. With an increase in the size of large gas pores in the center region, the UTS and elongation of the material decreases. In addition, the distribution of gas pores in the specimens and the areal fraction of gas pores >100 µm on cross sections can also affect the UTS and elongation to some extent. © Microscopy Society of America 2015 Source
Zhang Q.,Xian Jiaotong University |
Chen Y.,Xian Jiaotong University |
Fang J.,FAW Foundry Co.
Hsi-An Chiao Tung Ta Hsueh/Journal of Xi'an Jiaotong University
To design high-pressure casting die for box-like workpieces, a new optimization strategy for cooling channel arrangement is proposed, solid fraction of a box-like workpiece, and thermal balance, temperature field, thermal stress and thermal fatigue of a high-pressure casting die for workpieces are analysed by FE simulation. The relationship between cooling channel heat-transfer coefficient and flow rate in cooling channels is presented. In the cases of cooling channel arrangement along the cross and longitudinal directions, the die thermal stress, thermal fatigue and workpiece solidification are investigated with the increasing cooling channel intervals. Because the yield stress of die material varies with temperature, a factor related to thermal stress is applied to evaluate the margin of die safety under thermal stress. On the premise of the productivity effect and an appropriate solidification of workpieces, the cooling channel intervals ought to be increased as possible to decrease the mold thermal stress. When the channels are arranged with interval of 25 mm, the mold needs 6 cycles to reach thermal balance; and n gets less than 0.5, the area of the mold thermal stress and thermal fatigue is located 10 mm below the cavity. Source