首页|G20Mn5N铸钢中的微细观孔洞及其对应力分布的影响

G20Mn5N铸钢中的微细观孔洞及其对应力分布的影响

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为了准确分析铸造缺陷的影响,基于高分辨率三维X射线断层成像技术,对铸钢中的微细观孔洞信息进行统计,根据微细观孔洞的成因和形态,将其分为气孔、缩孔和气缩孔,并通过定义聚集趋势和亲和参数对这3类孔洞之间的空间关联性进行表征.此外,将通过X射线断层扫描获得的三维微细观孔洞信息映射到有限元分析软件中,用于预测微细观孔洞的形态、尺寸和分布对应力分布的影响.研究发现:铸钢材料中的细观缺陷会存在一些局部半径较小的拐点,而这些拐点正是引起应力集中的主要原因,因此不能将细观缺陷简化为理想孔洞;缺陷的圆整度和体积均对模型的应力集中有较大影响,缺陷圆整度越小、体积越大,引起的应力集中越大;铸钢件内部缺陷具有全局分布特征,缺陷位于试样表面时相较于其位于试样内部时,会导致更大的应力集中.
Micropores in G20Mn5N cast steel and their influence on stress distribution
To accurately analyze the impact of casting pores in steel,high-resolution 3D X-ray tomography technology was used to gather detailed statistical information about micropores.These micropores were classified as gas,shrinkage,and gas-shrinkage pores depending on their formation origin and morphology.Clustering tendencies and affinity parameters were defined to characterize the spatial correlations among these three types of pores.The 3D data from X-ray tomography scans were then integrated into finite element analysis(FEA)software to predict how micropore shape,size,and distribution influence stress distribution within the material.The results show that certain inflection points with small local radii within the cast pores are major contributors to stress concentration.Therefore,cast pores cannot be simply modeled as ideal spherical pores.The sphericity and volume of pores have a significant impact on the stress concentration of the model.Specifically,lower sphericity and larger pore volumes result in higher stress concentrations.Moreover,the internal pores of steel castings exhibit specific global distribution characteristics.Pores located on the surface of the specimen lead to significantly higher stress concentrations compared to those located inside the specimen.

cast steelmicroporesX-ray tomography3D reconstructionfinite element analysis

闫华东、靳慧

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东南大学土木工程学院,南京 211189

东南大学江苏省工程力学分析重点实验室,南京 211189

铸钢 微细观孔洞 X射线断层扫描 三维重建 有限元分析

2024

东南大学学报(英文版)
东南大学

东南大学学报(英文版)

影响因子:0.211
ISSN:1003-7985
年,卷(期):2024.40(3)