A METHOD OF AS-CAST CRACK PREDICTION BASED UPON NUMERICAL SIMULATION OF SOLIDIFICATION  

作　　者：X.S.Zheng S.Yao J.Z.Jin 

机构地区：[1]ResearchCenterofFoundryEngineering,DalianUniversityofTechnology,Dalian116024,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2004年第6期817-822,共6页金属学报（英文版）

基　　金：the National Natural Science Foundation of China(No.59995442);Specialized Research Fund for the Doctoral Program of Higher Education of China(No.2000014117).

摘　　要：Based on the numerical simulation of solidification of castings, a thermal stress formula and a thermal crack initiation criterion are established, which suggest that the cracks initiate at the two-thirds thickness of solidified layer from outside of castings. Cast steel wheels whose diameters are 800mm are employed to testify the positions of cracks through thermal ela- stic-plastic analyses and low magnifying structure observations conventionally. The results show that the numerical prediction of cracks coincides with the measured result, and the cracks do not necessarily follow where the defects such as shrinkage holes and porosities occur. It is also found that surface temperature control is an effective factor to avoid the crack formation.Based on the numerical simulation of solidification of castings, a thermal stress formula and a thermal crack initiation criterion are established, which suggest that the cracks initiate at the two-thirds thickness of solidified layer from outside of castings. Cast steel wheels whose diameters are 800mm are employed to testify the positions of cracks through thermal ela- stic-plastic analyses and low magnifying structure observations conventionally. The results show that the numerical prediction of cracks coincides with the measured result, and the cracks do not necessarily follow where the defects such as shrinkage holes and porosities occur. It is also found that surface temperature control is an effective factor to avoid the crack formation.

关 键 词：SOLIDIFICATION crack initiation crack prediction numerical simulation 

分 类 号：TG244[金属学及工艺—铸造]