Prediction and Verification of Casting Defects of Ductile Iron Crankshaft 在线阅读 下载PDF
Author of the article:HU Bo;YU Ning;LI Dejiang;TIAN Yingxin;ZENG Xiaoqin
Author's Workplace：School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;Shanghai Sandmann Foundry Co., Ltd., Shanghai 201805, China
Key Words：ductile iron crankshaft casting simulation casting defects
Abstract：
The casting process of nodular cast iron crankshaft was simulated by EKK CAPCAST casting simulation software, and the types, locations and sizes of possible defects during mold filling and solidification were predicted, and combined with the production test for verification. The simulation results show that the filling process of molten iron is stable and no turbulence occurs under the existing production conditions. However, during the solidification process, a large isolated molten pool area appeared in the fourth spindle neck, which had a relatively late solidification time and produced a large shrinkage stress. Shrinkage crack defects of about 6 mm^3 were easy to occur here. The simulated prediction results are confirmed in the experiment, and the fracture defect is found in the neck of the fourth spindle. The cast crankshaft is cut open and the volume of the fracture envelope is on the same order of magnitude as the volume of the predicted defect formation area. Metallographic observation and hardness characterization show that there are obvious differences in microstructure properties inside and outside the fracture, which are caused by the unsynchronization of solidification time.
