Zr-4合金板材微观组织异常条线现象的研究

摘要

采用金相显微镜、扫描电镜等检测手段对Zr-4合金板材微观组织中出现的异常条线现象进行研究,分析了Zr-4合金板材条线现象的本质、成因以及对其使用性能的影响.研究表明,Zr-4合金板材微观组织中出现的异常条线现象并不是裂纹、夹杂、氢化物、织构等缺陷的反映,而是由沿轧向成带状分布的粗大Zr(Fe,Cr)2第二相更容易遭受腐蚀造成的.此外,Zr-4合金板材微观组织中出现的条线现象对均匀腐蚀性能无明显影响,但带状分布的粗大第二相不利于板材的抗疖状腐蚀,并且会对板材的弯曲性能产生影响.%The abnormal string phenomenon in the microstructure of Zr-4 alloy plate was studied by means of optical microscope and scanning electron microscope. The nature and reason of the phenomenon were analyzed and the influence on the properties of Zr-4 alloy plate was also tested. The results show that the abnormal string phenomenon in the microstructure of Zr-4 alloy plate is not caused by the defects such as cracks,inclusions,hydride and texture,but rather the second phase of coarse Zr(Fe,Cr)2, which is more susceptible to corrosion. In addition, the string phenomenon in the microstructure of Zr-4 alloy plate has no obvious effect on uniform corrosion test, but the coarse second phase with zonal distribution is bad for nodular corrosion property, and has adverse effect on the bending property of Zr-4 alloy plate.