Development of etching paste for serial number restoration on aluminum engine block.
aluminum
engine number
etching paste
obliteration
restoration
Journal
Journal of forensic sciences
ISSN: 1556-4029
Titre abrégé: J Forensic Sci
Pays: United States
ID NLM: 0375370
Informations de publication
Date de publication:
Jul 2023
Jul 2023
Historique:
revised:
10
05
2023
received:
22
12
2022
accepted:
23
05
2023
medline:
2
6
2023
pubmed:
2
6
2023
entrez:
2
6
2023
Statut:
ppublish
Résumé
Engine numbers, which involve information regarding the engine type, production number, and year and place of manufacture, are used for identification purposes. Comprising of unique alphanumeric characters, the engine numbers are fully or partially obliterated especially in auto theft and smuggling cases to conceal the origin, identity, and owner of vehicles. The limitations of the current restoration techniques such as the difficulty of using chemical liquid etching in vertical sites, the restrictions of magnetic and optical methods, and the applicability of several techniques like electron backscatter diffraction only in the laboratory environment prompt the development of new techniques. In view of these limitations and the importance of restoring engine numbers in criminal investigations, this unique study aimed to develop an etching paste that would restore the effaced characters on a real aluminum alloy engine block. The characters which were cold-stamped on the engine block were milled at varying depths and restoration attempts were conducted using etching pastes formed with different chemicals and materials. The analyses indicate that the etching paste formed with 200 mg of perlite, 400 mg of iron powder, and 450 μL of 20 M NaOH provided restoration to a good extent. The prevention of over-etching through the controlling of the chemical reaction and the cost-effectiveness appears to be the advantages of this technique. The success of recovery on the real engine block, the facilitation of restoration on curved surfaces, and the chance of on-site usage will likely make the etching paste a widely used tool in serial number restoration.
Identifiants
pubmed: 37265122
doi: 10.1111/1556-4029.15303
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
1325-1329Informations de copyright
© 2023 American Academy of Forensic Sciences.
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