主管：中华人民共和国司法部
主办：司法鉴定科学研究院
ISSN 1671-2072  CN 31-1863/N
中国司法鉴定

中国司法鉴定 ›› 2023 ›› Issue (5): 64-71.DOI: 10.3969/j.issn.1671-2072.2023.05.009

• 鉴定科学 • 上一篇    下一篇

腐蚀条件下铁丝剪切痕迹修复显现及对同一认定影响的研究

李大武1，臧泰琦1，周昊1，等   

  1. 1.中国刑事警察学院 刑事科学技术学院 痕迹检验鉴定技术公安部重点实验室，辽宁 沈阳110854；2.中国刑事警察学院 禁毒与治安学院，辽宁 沈阳 110854
  • 收稿日期:2022-08-06 出版日期:2023-09-15 发布日期:2023-11-30
  • 作者简介:李大武（1980—），男，副教授，博士，主要从事公安科技及物证的检验鉴定研究。E-mail:67021063@qq.com
  • 基金资助:
    公安部科技基础专项（2021JC07，2022JC04）；上海市刑事科学技术研究院现场无证重点实验室资助课题（2016XCW2K03）；痕迹检验鉴定技术公安部重点实验室开放课题（HJKF201911）。

Research on the Restoration of Cutting Trace of Iron Wire under Corrosive Condition and Its Impact on the Forensic Impression Identification

LI Dawu1, ZANG Taiqi1, ZHOU Hao1, et al   

  1. 1. Key Laboratory of Impression Evidence Examination and Identification Technology, Ministry of Public Security, College of Forensic Science, Criminal Investigation Police University of China, Shenyang 110854, China; 2. School of Drug Control and Public Order, Criminal Investigation Police University of China, Shenyang 110854, China
  • Received:2022-08-06 Published:2023-09-15 Online:2023-11-30

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摘要： 目的 工具痕迹特征修复与增强是提高工具痕迹利用率的方法，用以比较和分析铁丝剪切痕迹腐蚀前后特征变化对检验鉴定的影响。方法 采用中性盐雾实验方式腐蚀铁丝剪切痕迹，探讨了物理和化学处理方法对腐蚀线条痕迹特征的影响，优化了铁丝表面腐蚀产物的清除工艺参数。结果 生成的腐蚀产物容易遮挡表面的线条痕迹而失去检验鉴定条件，可通过物理或者化学等方法对表面特征进行修复，达到检验鉴定的要求；铁丝表面线条痕迹特征的化学修复工艺参数为VHCl ∶ VH2O 为1∶2，酸洗时间4 min；超声振荡清洗法工艺参数为超声频率40 kHz，溶液温度30 ℃，75 %乙醇介质下清洗时间大于10 min。量化数据分析表明，线条痕迹特征的稳定性与线痕宽度正相关，线痕宽度≤0.01 mm的特征极易发生改变，线痕稳定性差，无法通过物理或化学方法完整显现，检验鉴定价值较低；线痕宽度大于0.03 mm的特征受环境影响较小，修复的概率可达100 %。结论 该方法可为检验鉴定提供技术支持和参考。

关键词: 腐蚀, 痕迹特征, 线条痕迹, 氧化膜, 同一认定

Abstract: Objective The restoration and enhancement of tool mark features helps to improve the utilization of tool marks. This research compared and analyzed the features of cutting trace of iron wire before and after corrosion, to study its influence on the forensic identification of cutting trace. Methods The cutting trace of iron wire was corroded by neutral salt spray test. The influence of the physical and chemical treatment methods on the corrosion line marks on the surface of the  iron wire was discussed. The processing parameters for removing the superficial corrosion products, which block the trace of surface lines, were optimized. Results Using physical or chemical methods to remove the corrosion products can improve the surface observation effect and facilitating the identification of tool marks. The chemical method for restoring the trace on the surface of iron wire used hydrochloric acid-water solution（VHCl ∶ VH2O =1∶2） to wash the surface for 4 min. The physical method used ultrasonic bath, washing the iron wires with 75 % ethanol at 40 kHz for more than 10 min. The temperature was set at 30 ℃.The features of line trace which width was no more than 0.01 mm were not stable and cannot be completely restored by physical or chemical methods. On the other hand, the features of line trace which width was larger than 0.03 mm were 100 % restored. Conclusion This method can provide technical support and reference for the forensic identification of tool marks.

Key words: corrosion, trace characteristic, line trace, oxidized film, forensic identification

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