扫描电镜/X射线能谱仪检验电流斑规范化方法探讨

Standardized Electrical Marks Examination by Scanning SEM/EDS and Conclusion Analysis

目的探讨电流斑皮肤金属化的机理、检材提取处理和扫描电镜/能谱仪检验规范化方法,对检验结果进行分析和价值判断。方法用扫描电镜/能谱检验,采用低倍大窗口覆盖损伤区域采集平均元素能谱图,并在可能的金属元素富集区域寻找球形金属颗粒。结果扫描电镜下可观察到散在的孔穴、细胞碎屑、龟裂、裂隙等特征,有些电流斑可检出金属元素,其中部分电流斑可发现球形金属颗粒。结论采用规范化的检材提取、处理和检验方法可消除随意性方法造成错检的可能。电流斑皮肤上异常含量的金属附着可支持病理检验符合电流斑表现的结论,同时也为电击导体的推断和金属元素成分比对提供依据。球形金属颗粒的发现揭示存在电弧高温的可能性极大,可强力支持病理检验符合电流斑表现的结论。

Objective To discuss on the mechanism of the metallization of skin, the extraction and preparation of samples, the standardization of SEM/EDS examination, the analysis and evaluation of the conclusion. Method Low magnification was used to collect the average elemental composition in a large scale so that the injured area could be covered. The presence of spherical metal particles was searched in possible area. Results Using SEM, scattered pockets, cell debris, cracks, fissures and other features were observed. Metal elements were detected on some electrical marks, and spherical metal particles were found. Conclusion With standardized extraction, preparation and examination method, the possibility of wrong conclusion could be eliminated. The abnormal content of metal elements on the skin with SEM/EDS analysis provides support to the positive pathological conclusion. Moreover, the detection of metal elements helps to deduce the electric shock conductor as well as to make sure if the composition of the metal elements on the skin matches that of the conductor. The presence of spherical metal particles reveals possible very high temperature due to the electric are, thus strongly supports the positive pathological conclusion.