Recovering obliterated engraved vehicle identification number on vehicle frame surfaces by etching technique

摘要

Chemical etching,which is the most sensitive method to recover obliterated serial numbers on metal surfaces.This paper studied the method of recovering obliterated engraved vehicle identification number on vehicle frame surfaces by etching technique.Experiment research indicates that for vehicle frame materials containing Al and Si components,the use of concentrated hydrochloric acid:acetic acid:ethanol=2:1:1(volume ratio) reagent shows good effectiveness; For vehicle frame materials Mn and Si composition,the use of concentrated nitric acid:acetic acid:ethanol=1:1:1 (volume ratio) shows good effectiveness.This recovering method has far-reaching application prospects,especially in the robbery cases involving vehicle identification numbers juggled.