Metal Objects Mapping After Small Charge Explosions: A Study on AISI 304Cu Steel With Two Different Grain Sizes

• NCJ Number: 214490
• Journal: Journal of Forensic Sciences Volume: 51 Issue: 3 Dated: May 2006 Pages: 520-531
• Author(s): Donato Firrao M.Sc.; Paolo Matteis Ph.D.; Giorgio Scavino; Graziano Ubertalli; Maria G. Ienco; Gabriella Pellati; Paolo Piccardo Ph.D.; Maria R. Pinasco; Enrica Stagno; Girolamo Costanza Ph.D.; Roberto Montanari; Maria E. Tata Ph.D.; Giocanni Brandimarte; Santo Petralia
• Date Published: May 2006
• Length: 12 pages
• Publication Format: Article
• Publication Type: Report (Study/Research)
• Language: English
• Country: United States of America

Annotation

This study examined damage to stainless steel metal after small-charge explosions.

Abstract

The explosions caused limited damage to the metal that could be observed with the naked eye when the charge (spherical charges of 54.5 or 109 g TNT equivalent mass) was placed at less than 10 cm from the target. At distances over 10 cm, observable deformations of the metal declined significantly. Surface optical metallography (OM), scanning electron microscopy (SEM), and scanning tunneling microscopy (STM) detected microstructural modifications of AISI 304Cu steel disks by small-charge explosions. Surface OM and SEM revealed partial surface melting zones with recrystallization effects and intense mechanical stress at the surface. For the purpose of determining the existence of explosions as well as the location and size of any explosive charge, the maximum charge-to-target distance was 21.5 cm for the charges used. Beyond this distance, no change in the surface of the metal could be detected. Tables show the maximum charge-to-target distance at which change in the metal disappeared for each charge or metal grain size. Descriptions of study methods address specimen preparation and experimental setups. 11 figures, 6 tables, and 25 references