...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Materials at High Temperatures >Microstructural changes in creep exposed P91 steel weld joint
【24h】

Microstructural changes in creep exposed P91 steel weld joint

机译：蠕变暴露P91钢焊接接头的组织变化

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Cast plates made of 9Cr – 1MoV creep resistant steel were joined together using the GTAW and SMAW methods. Creep testing was carried out at a temperature range from 525℃ to 625℃ and a stress range from 50 to 240MPa. The microstructure of crept specimens was compared with weld joint at conditions after PWHT and the base material before welding. Substructures were investigated in the base material, the heat affected zones and the weld metal. Different kinetics of precipitation reactions in individual zones caused changes in creep strength and unexpected transition from Type IV cracking to Type I cracking at long creep exposure at 625℃. After creep tests at temperatures above 550℃ for about 30,000 hours, coarse particles of Laves phase were observed. In addition, small plates of Z-phase were detected after creep tests at 625℃. Precipitation of Laves phase occurred in the weld metal predominately and caused depletion of solid solution about molybdenum. If the lowest stress were applied at 625℃, the growth of the Laves phase was the dominant process, which caused a significant softening and rupture in the weld metal. This effect prevailed over accumulation of cavitation failure in the heat affected zones that caused fracture of the other specimens.
机译：使用GTAW和SMAW方法将9Cr – 1MoV抗蠕变钢制成的铸板连接在一起。蠕变测试是在525℃至625℃的温度范围和50至240MPa的应力范围内进行的。将预蠕变后的条件和焊接前的母材的蠕变试样的微观结构与焊接接头进行了比较。研究了基础材料，热影响区和焊接金属中的亚结构。在625℃下长时间的蠕变暴露，单个区域中不同的沉淀反应动力学导致蠕变强度发生变化，并从IV型开裂突然转变为I型开裂。在550℃以上的温度下进行了30,000小时的蠕变测试后，观察到Laves相的粗颗粒。另外，在625℃下蠕变测试后，检测到小的Z相板。 Laves相的析出主要发生在焊缝金属中，并导致固溶体中的钼耗尽。如果在625℃施加最低的应力，则Laves相的生长是主要过程，这会导致焊缝金属明显软化和破裂。这种影响普遍存在于热影响区域中空化故障的积累上，而空化故障导致其他样品破裂。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号