标题：The behavior of second phase particles in a Ti-Nb microalloyed steel during welding thermal cycle
作者：Chen, Mao Ai ;Wu, Chuan Song
作者机构：[Chen, Mao Ai ;Wu, Chuan Song ] MOE Key Lab for Liquid-Solid Structure Evolution and Materials Processing, Shandong University, Jinan 250061, China
会议名称：2014 International Conference on Materials Science and Engineering Technology, MSET 2014
会议日期：28 June 2014 through 29 June 2014
来源：Advanced Materials Research
关键词：Microalloyed steel; Second phase particle; Weld thermal cycle
摘要：The behavior of second-phase particles in a microalloyed steel during weld thermal cycle has been investigated using analytical electron microscopy. All the particles in the base metal contains Nb and Ti, and the Nb weight fraction of the analyzed particles ranged from 0.22 to 0.85. During the heating stage of the weld thermal cycle, the small particles which were rich in Nb disappeared through complete dissolution and the large particles survived the weld thermal cycle with Nb weight fraction decreased. With a high cooling rate (t8/5 no greater than 60s), only heterogeneous re-precipitation occurred during cooling. With a low cooling rate (t8/5 = 120s), homogenous re-precipitation also occurred, producing a large number of small Nb-rich particles during cooling. © (2014) Trans Tech Publications, Switzerland.