| 局部硬化区对焊接热影响区断裂萌生的影响 |
| |
| 引用本文： | 荆洪阳,霍立兴,张玉凤,丰田政南,南二三吉.局部硬化区对焊接热影响区断裂萌生的影响[J].天津大学学报(英文版),1995(1). |
| |
| 作者姓名： | 荆洪阳 霍立兴 张玉凤 丰田政南 南二三吉 |
| |
| 作者单位： | 天津大学，日本大阪大学 |
| |
| 摘 要： | 采用二维有限元数值方法分析了焊接热影响区粗晶区（ＣＧＨＡＺ）中局部硬化区（ＬＨＺ）的作用。当含有ＬＨＺ时，大大提高了ＬＨＺ内的应力并引起应变在ＬＨＺ和基体界面处产生不连续分布。ＬＨＺ的形状强烈影响ＬＨＺ内部的应力，在细长ＬＨＺ内几乎整体均呈现高应力分布，而块状ＬＨＺ仅在边缘区域出现应力集中。即使ＬＨＺ含量相同，随ＬＨＺ细长比的增大，ＬＨＺ内峰值应力及高应力区面积增加，说明细长ＬＨＺ容易在低应力水平下诱发断裂。这一结果在高强钢焊接热影响区ＣＴＯＤ试验中得到证实。含细长ＭＡ组元的ＣＧＨＡＺ在低得多的ＣＴＯＤ水平下发生断裂，因此控制ＭＡ组元的形状能够大大改善ＣＧＨＡＺ的韧性。
|
| 关 键 词： | 热影响区粗晶区，局部硬化区，应力，MA组元 |
EFFECT OF LOCAL HARD ZONE ONFRACTURE INITIATION OF WELD HAZ |
| |
| Jing Hongyang, Huo LiXing, Zhang Yufeng.EFFECT OF LOCAL HARD ZONE ONFRACTURE INITIATION OF WELD HAZ[J].Transactions of Tianjin University,1995(1). |
| |
| Authors: | Jing Hongyang Huo LiXing Zhang Yufeng |
| |
| Abstract: | The effect of the local hard zone (LHZ) distributed in the coarse grained HAZ (CGHAZ) has been analyzed by 2-dimensional FEM on a mechanical model of the weld CGHAZ. The existence of the LHZ elevates considerably the stress in LHZ and causes the discontinuity of strain at the boundary between the LHZ and the matrix. The stress distribution in the LHZ is strongly affected by the shape of the LHZ. In a slender LHZ almost the whole region in the LHZ is exposed to elevated stress, whereas in the massive LHZ only the edge region sustains high stress. The longer the LHZ becomes, the more the highly stressed area, and the peak stress in the LHZ grows even under the same volume fraction of the LHZ. These results indicate that the slender LHZ brings about unstable fracture at a lower load level than the blocky LHZ. This tendency was confirmed by CTOD test results on the weld CGHAZ of a high-strength steel. The CGHAZ with elongated M-A constituents fractures at apparently lower critical CTOD than the CGHAZ with massive M-A constituents. In conclusion, the control of the shape of the M-A constituent has a striking effect on the toughness improvement of CGHAZ. |
| |
| Keywords: | coarse grained HAZ local hard zone stress M-A constituent |
| 本文献已被 CNKI 等数据库收录！ |
