A finite element approach to study the influence of cast pores on the mechanical properties of the Ni-base alloy MAR-M247
A finite element approach to study the influence of cast pores on the mechanical properties of the Ni-base alloy MAR-M247
复制标题
有限元方法研究铸造气孔对镍基合金MAR-M247力学性能的影响
DOI：
10.1016/j.msea.2013.02.067
复制
发表时间：
2013
期刊：
影响因子：
6.4
通讯作者：
E. Werner
中科院分区：
文献类型：
--
作者：
T. Taxer;C. Schwarz;W. Smarsly;E. Werner
提出了一种表征多孔MAR-M247微观结构的体积元模型，用于研究铸态气孔对有效力学性能的影响。为了确保材料的真实表现，多孔铸造样品通过计算机断层扫描进行分析。建模方法追求基于简单而灵活的合成孔隙几何形状的自动微观结构生成，这有利于参数化研究，例如探索不同孔隙体积分数和不同孔隙形态的影响。这些体积单元模型的有限元模拟所预测的有效杨氏模量、有效剪切模量和塑化开始时间表明了孔隙度特征对材料性能的影响；而对于弹性材料性能而言，孔隙体积分数是主要因素，塑性性能对实际孔隙形态和分布非常敏感。为了将微观尺度上得到的结果融入到实际构件的数值模拟中，提出了一种顺序尺度耦合方法。使用这种方法的多孔拉伸试验试样的示例性有限元分析显示。
A volume element model representing the microstructure of porous MAR-M247 is presented which is used to study the influence of cast pores on effective mechanical properties. To ensure a realistic representation of the material, porous cast samples are analyzed by computed tomography scans. The modeling approach pursues an automated microstructure generation based on simple but flexible synthetic pore geometries which is advantageous for parametric studies, e.g. exploring the influence of a varying pore volume fraction and different pore morphologies. The effective Young's modulus, the effective shear modulus and the onset of plastification predicted by finite element simulations of these volume element models provide an indication of the influence of the characteristics of the porosity on the material behavior: whereas for the elastic material properties the pore volume fraction is the major factor, plastic behavior is very sensitive to the actual pore morphology and distribution. To incorporate the results gained on the microscopic scale into numerical simulations of actual components a sequential scale coupling approach is proposed. An exemplary finite element analysis of a porous tensile test specimen using such an approach is shown.