【作者】 刘吉斌； 胡伦骥； 王玉涛； 缪凯；

【Author】 Liu Jibin, Hu Lunji, Wang Yutao, Miao Kai Technology Center of Wuhan Iron and Steel (Group) Corporation Huazhong University of Science and Technology

【机构】 武汉钢铁(集团)公司技术中心； 华中科技大学材料学院；

【摘要】 本文对800MPa超细组织钢焊接热影响区的组织转变行为进行了研究。在较宽的冷却速度范围内,焊接热影响区发生的组织转变呈现中温转变特征。在较快的冷却速度条件下,得到的贝氏体板条间无碳化物析出物和M-A岛。当冷却速度小于9℃/s时, 焊接热影响区过热区出现明显软化。采用数字微分的方法对连续冷却过程中的组织转变速率进行了分析,试验结果表明,当冷却时间t8／5大于7秒时,800MPa超细组织钢的焊接热影响区组织转变速率明显降低。更多还原

【Abstract】 The transformation behavior and microstructure development in the heat affected zone of a 800MPa grade ultra fine structured steel was investigated. It was found that the HAZ has a medium temperature transformation characteristics in a wide range of cooling rates, with the bainite sheaves consisting of bainite ferrite plates without carbide precipitation and M-A in the fast cooling regime. When the cooling rate is below 9℃/s, the welding HAZ would have an obvious softening. The analysis of transformation rate in continuous cooling processes was completed by numerical differential method. The result indicated that the microstructure transformation of the HAZ in 800MPa grade ultra fine structured steel changed sharply to slow speeds when the cooling time t8/5 is longer than 7s.更多还原