Effect of Multi-axial Stress on Creep Damage Behavior for Notched Specimen of P92 Steel
Effect of Multi-axial Stress on Creep Damage Behavior for Notched Specimen of P92 Steel
复制标题
多轴应力对P92钢缺口试样蠕变损伤行为的影响
DOI：
10.1115/pvp2013-97486
复制
发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Takashi Matsuzaki
中科院分区：
文献类型：
--
作者：
Haruhisa Shigeyama;Ryuji Sugiura;A. Toshimitsu Yokobori;Jr.;Takashi Matsuzaki
本文采用P92钢的C（T）型侧槽试样和圆形缺口圆棒试样进行了断续蠕变裂纹扩展试验。为了研究P92钢在多轴应力场作用下的蠕变裂纹扩展和损伤扩展行为，在间断试验后对缺口和裂纹尖端进行了截面观察。由显微维氏硬度和空洞率随蠕变时间变化的测量结果表明，在缺口或裂纹尖端附近存在低硬度和高空洞率区域。然后，三维弹塑性蠕变分析进行了每个标本。从有限元分析的结果来看，高静水应力和高三轴度因子的区域与每个试样的高空隙面积分数的区域吻合得很好。这一结果表明，多轴应力场有助于空洞的形成。讨论了三轴度因子的绝对值和梯度对空洞形成的影响。
In this study, interrupted creep crack growth tests were conducted using C(T) specimen with side-grooves and circular notched round bar specimen of P92 steel. After the interrupted tests, to investigate the creep crack growth and damage progression behaviors of P92 steel under the multi-axial stress field, cross-sectional observations around the notch and crack tip were conducted. From the measurement results of the change of micro Vickers hardness and void area fraction with creep time, it was indicated that the region of low hardness and high void area fraction were existed near the notch or crack tip. Then, three-dimensional elastic-plastic creep analyses were conducted for each specimen. From the results of finite element analyses, the regions of high hydrostatic stress and high tri-axiality factor were in good agreement with the region of high void area fraction for each specimen. This result indicated that the multi-axial stress field contributes to the void formation. Furthermore, the effects of the absolute value and gradient of tri-axiality factor on void formation were discussed.