论文部分内容阅读
针对异型坯生产中出现较多表面裂纹的问题,在前期铸坯凝固过程热力行为研究基础上,提取凝固坯壳的温度与应力数据,使用扩展有限元方法,结合材料损伤力学、子模型技术模拟预制表面裂纹的扩展情况。研究结果表明:在裂纹尖端区域出现应力集中,应力值明显高于无裂纹位置;当应力集中区域最大主应力达到临界值时单元开裂,裂纹扩展。R角处预制纵裂纹扩展量最大,与拉坯方向呈75°、45°裂纹次之;预制表面横裂纹在沿横向扩展一个网格后扩展方向出现弯折,裂纹最终扩展方向均为沿纵向。
Aiming at the problem of more surface cracks in the blank production, the temperature and stress data of the solidified shell are extracted based on the study of the thermal behavior during the solidification process of the precast slab. Using the extended finite element method and the material damage mechanics and the submodeling technology simulation Prefabricated surface crack propagation. The results show that stress concentration occurs in the crack tip area, and the stress value is obviously higher than that in the non-cracked area. When the maximum principal stress in the stress concentration area reaches the critical value, the crack and crack propagation occur. The prefabricated longitudinal crack propagation is the largest at R angle, which is 75 ° and 45 ° second with the direction of drawing. The prefabricated surface transverse crack appears bending in the direction of extension along a grid extending transversely, and the final crack propagation direction is along the longitudinal direction .