Creep damage behavior of Mod.9Cr-1Mo steel welded joint

被引：11

作者：

Hongo, Hiromichi ^{[1
]}

Tabuchi, Masaaki ^{[1
]}

Li, Yongkui ^{[1
]}

Takahashi, Yukio ^{[2
]}

机构：

[1] National Inst. for Materials Sci., Sengen

[2] Central Res. Inst. of Electric Power Industry, Iwatokita

来源：

Zairyo/Journal of the Society of Materials Science, Japan | 2009年 / 58卷 / 02期

关键词：

Creep void; Damage mechanics; FEM; Mod.9Cr-1Mo Steel; Type-IV damage; Welded joint;

D O I：

10.2472/jsms.58.101

中图分类号：

学科分类号：

摘要：

Mod.9Cr-1Mo steel has been used for boiler components in ultra-supercritical (USC) thermal power plants. The creep strength of welded joint of this steel decreases due to Type-IV creep cracking formed in heat affected zone (HAZ) at high temperatures. The present paper aims to clarify the damage process and microstructural degradation of the welded joint. Long-term creep tests for base metal, simulated HAZ and welded joints were conducted at 550, 600 and 650°C. Furthermore, creep tests of thick welded joint specimens were interrupted at several time steps for 600°C, 90MPa, and the damage distribution was measured. It is found that creep voids initiate at early stage of creep life (t/t r = 0.2), and coalesce into the crack at the later stage of life (t/t r = 0.9). Creep damages concentrate mostly at a quarter depths of the plate thickness in the fine-grained HAZ. The experimental creep damage distribution was compared with the computed one by using the damage mechanics analysis. © 2009 The Society of Materials Science, Japan.

引用

页码：101 / 107

页数：6

共 12 条

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