Abstract: Short circuit of wires is one of the important causes of electrical fires. The current national standard divides wire short circuit marks into primary short circuit marks before ignition and secondary short circuit marks caused after ignition. However, the identification in the current national standard only stays at the stage of qualitative judgment. The quantitative analysis of the characteristics of short circuit marks on copper wires at fire sites has become the main focus of attention for China and other countries researchers. This paper applies Micro CT technology to perform fault scanning detection on copper wire short circuit melt marks and reconstruct 3D image data of copper wire short circuit melt marks. Based on this, the internal pore morphology and distribution of copper wire short circuit melt marks are statistically analyzed, summarized, and summarized. Research has shown that Micro CT can comprehensively collect the overall morphology and internal pore characteristics of copper wire short-circuit melt marks. There are differences in the characteristic data of pore radius, surface area, and tightness between primary and secondary short-circuit melt marks, which can provide new theoretical basis for qualitative analysis methods and quantitative analysis criteria of short-circuit melt marks.

Key words: Micro CT, short circuit melt mark, hole characteristic, fire evidence identification