690合金与152合金焊接热影响区微观组织研究  

Microstructure of Heat-Affected Zone in a Weld Joint between Alloy 690 and Alloy 152

作　　者：聂书红[1] 梁政强[1] 

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《核动力工程》2017年第4期139-144,共6页Nuclear Power Engineering

摘　　要：应用电子背散射衍射(EBSD)、扫描电镜(SEM)和显微硬度仪研究了压水堆(PWR)压力容器(RPV)控制棒驱动机构(CRDM)管嘴690合金与152合金焊接热影响区上部、中部和根部的残余应变分布、显微硬度、晶粒平均取向差(GAM)、晶粒边界显微结构和金相特征。研究结果表明:残余应变从上部到下部逐渐减少,最大残余应变5.15%,位于最后焊接的上部热影响区;重合位置点阵∑3边界平均分数从上部到下部逐渐增加,最小∑3边界平均分数是46.6%,显著低于基体金属的68%。因此认为,最后焊接的上部热影响区具有最高应力腐蚀破裂(SCC)敏感性。The distributions of residual strains, micro-hardness, intra-grain average misorientation（GAM）, grain boundary microstructure and metallurgical characteristics were investigated at the top, middle and root of the heat-affected zone of a weld joint between pressurized water reactor （PWR） control rod drive mechanism （CRDM） Nozzle Alloy 690 and Alloy 152 using electron backscatter diffraction （EBSD）, scanning electron microscopy （SEM） and micro-hardness tester. The results showed that the residual strain decreased from the last welding top of the weld to root, the maximum residual strain is 5.15% at the top of the last weld; the average fraction of coincident site lattice ∑3 special boundaries increased from the last welding top of the weld to root, the minimum fraction of ∑3 special boundaries is 46.6%, which is remarkably less than that 68% of the base 690 alloy. The HAZ at the top of the weld is considered to sustain the highest stress corrosion cracking （SCC） susceptibility.

关 键 词：热影响区 金相特征 残余应变 晶粒平均取向差 晶粒边界显微结构 

分 类 号：TL172[核科学技术—核能科学]