便携式X射线荧光光谱仪检测贫铀棒材表面镍锌镀层厚度

为了确保贫铀棒材表面防腐性能满足使用要求,需要准确地测量产品表面的镍镀层和锌镀层厚度。采用便携式X射线荧光光谱仪(PXRF)对贫铀棒材表面双镀层的各层厚度进行检测,实现了对镍镀层和锌镀层厚度非破坏性的测量。选用特征谱线强度分布均匀的镀层样品和未镀镀层的贫铀基体样品,采用PXRF检测,结果表明,基体射线对检测谱线无干扰。分别选取相同厚度镍镀层、不同厚度锌镀层的样品,相同厚度锌镀层、不同厚度镍镀层的样品,以及镍镀层、锌镀层厚度均不相同的样品,采用PXRF进行检测,结果表明,实验方法可识别相同基体上不同厚度的镍镀层和锌镀层,可实现镍锌组合镀层中两种镀层厚度的同时测量。根据贫铀棒材样品结构特点和镍镀层和锌镀层厚度的技术要求,设计制作了对比试样,分别绘制贫铀棒材样品镍镀层和锌镀层厚度与其对应特征峰强度的校准曲线,结果表明,校准曲线线性相关系数r均不小于0.999 4。采用实验方法检测贫铀棒材样品表面镍镀层和锌镀层厚度,同时在任意圆周上均匀地取6个检测点,采用金相显微镜法进行检测求得平均值,结果表明,实验方法测定结果相对标准偏差(n=6)不大于5.1%;与金相显微镜法基本一致,两种方法差值为-1.57~1.70 μm。

Detection of nickel and zinc coating thickness on the surface of depleted uranium bar by protable X-ray fluorescence spectrometer

In order to ensure the anti-corrosion property of depleted uranium bar surface to meet the requirements, it is necessary to accurately measure the thickness of nickel coating and zinc coating on the product surface. Protable X-ray fluorescence spectrometry (PXRF) was used to detect the thickness of the double coatings on the surface of depleted uranium bar, and the nondestructive measurement of the thickness of nickel coatings and zinc coatings was realized. The coating samples with uniform intensity distribution of characteristic spectral lines and the depleted uranium matrix samples without coating were selected and detected by PXRF. The results showed that the matrix rays had no interference with the detection spectral lines. The samples with the same thickness of nickel coating and different thickness of zinc coating, the samples with the same thickness of zinc coating and different thickness of nickel coating, and the samples with different thickness of nickel coating and zinc coating were selected for detection by PXRF. The results showed that the experimental method could identify the nickel coating and zinc coating with different thickness on the same substrate, and it could realize the simultaneous measurement of the thickness of two coatings in the nickel zinc composite coating. According to the structural characteristics of depleted uranium bar samples and the technical requirements for the thickness of nickel coating and zinc coating, the comparison samples were designed and prepared. The calibration curves between the thickness of nickel coating and zinc coating of depleted uranium bar samples and the corresponding characteristic peak intensity were fitted. The results showed that the linear correlation coefficients (r) of the calibration curves were not less than 0.999 4. The thickness of nickel coating and zinc coating on the surface of depleted uranium bar sample was measured according to the experimental method. At the same time, six testing points were uniformly taken on any circumference, and the average value was obtained by the metallographic microscope method. The relative standard deviations (RSD,n=6) were not more than 5.1%. The results showed that measurement results of the experimental method were basically consistent with those obtained by the metallographic microscope method. The difference between two methods was -1.57-1.70 μm.