Fatigue crack growth mechanism of Ni-based weld metal in a 9% Ni steel joint

被引：14

作者：

Li, Kejian ^{[1
,2
]}

Wang, Xue ^{[1
,2
]}

Rui, Shao-Shi ^{[1
,2
]}

Li, Xiaogang ^{[1
,2
]}

Li, Shanlin ^{[1
,2
]}

Sun, Qixing ^{[1
,2
]}

Zhang, Yu ^{[1
,2
]}

Cai, Zhipeng ^{[1
,2
,3
,4
]}

机构：

[1] Tsinghua Univ, Dept Mech Engn, Beijing 100084, Peoples R China

[2] Minist Educ, Key Lab Adv Mat Proc Technol, Beijing 100084, Peoples R China

[3] Tsinghua Univ, State Key Lab Tribol, Beijing 100084, Peoples R China

[4] Tsinghua Univ, Collaborat Innovat Ctr Adv Nucl Energy Technol, Beijing 100084, Peoples R China

来源：

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING | 2022年 / 832卷

基金：

中国国家自然科学基金; 国家重点研发计划;

关键词：

Fatigue crack growth; C-276 weld metal; 9% Ni steel; Fractography; Crystallographic analysis; EBSD; PROPAGATION BEHAVIOR; HEAT-TREATMENT; MICROSTRUCTURE; PERFORMANCE; SUPERALLOY;

D O I：

10.1016/j.msea.2021.142485

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

This research focused on the impact of temperature and driving force Delta K on the fatigue crack growth (FCG) mechanism of C-276 Ni-based weld metal in a 9% Ni steel joint. On one hand, the FCG resistance increased due to higher yield strength at 77 K than at room temperature (RT), and the decrease of FCG rate can be well explained by Weertman's model. On the other hand, critical Delta K values (37.5 MPa m(1/2) at 77 K and 30.2 MPa m(1/2) at RT) existed in the process of FCG, accompanied by the transition of FCG mechanism at both 77 K and Delta T. In detail, the fatigue crack mainly propagated in a quasi-cleavage mode at a lower Delta K level at 77 K, in a single-slip mode at a higher Delta K level at 77 K or a lower Delta K level at Delta T, and in a multi-slip mode at a higher AK level at Delta T. Furthermore, the dislocation-precipitate interaction was enhanced and even provided favourable locations for FCG at a higher Delta K level at RT, leading crack to propagate via linking after the formation of micro-cracks and micro-voids near precipitates.

引用

页数：14

共 73 条

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