AFTE Store - Serial Number Restoration on Titanium Firearms

Although effective reagents and methods of application have already been established for serial number restoration on several types of metal, titanium has been relatively unexplored in forensic literature. Based on the increased use of titanium in modern firearms, it was the goal of this research to find a reagent that would successfully etch titanium to restore obliterated serial numbers. Eight room temperature and heated reagents were applied to titanium samples. Only one of the eight reagents had a visible reaction with the metal and was further tested. Using eleven titanium samples containing markings with four different methods of application, concentrated hydrochloric acid was applied to the heated titanium samples and allowed to remain on the metal for variable lengths of time. Markings on ten of the eleven samples were fully or partially restored. Based on these results, this novel approach to serial number restoration on titanium firearms has clear potential for widespread use in serial number restoration.