核燃料棒端塞用冷轧锆合金棒材横截面低倍组织异常现象的研究

针对锆合金棒材在皮尔格冷轧中出现的横截面芯部低倍组织异常现象，用光学金相、扫描电子显微镜(SEM)、X-射线衍射(XRD)、硬度法、密度法等手段对冷轧锆-4合金棒材芯部低倍组织异常现象的本质、产生原因以及对使用性能的影响等进行了全面分析和研究。研究认为冷轧锆-4合金棒材横截面芯部出现的低倍组织异常现象并不是存在缺陷的表现，而是轧制载荷使芯部产生了不利于耐酸浸蚀的织构造成的；这种异常现象的存在不会威胁到其在反应堆中的安全性，在反应堆环境下可安全使用。

Studies on Abnormal Morphology of Cross Section in Cold-Pilgered Zr-4 Bar Used As End Caps of Nuclear Fuel Rods

Abnormal morphology appears easily in the cross section of cold-pilgered zirconium alloy bar due to improper die design or/and improper deformation ratio distribution. Causes and its effects on usability were investigated in this paper by optical microscopy(OM), scanning electron microscopy(SEM), X-ray diffraction(XRD), hardness and density, etc. Studying results prove that such abnormal phenomena are not exhibition of defects; however result from preferred orientation with low acid corrosion resistance brought by cold pilgering; such abnormal phenomena have no effects on usability of cold-pilgered bars, cold-pilgered zirconium alloy bar with abnormal phenomena can still serve reactors safely.