SEM Microstriation Characterization of Bullets and Contaminant Particle Identification

Abstract

Recent applications of the scanning electron microscope (SEM) have been in areas such as paint samples evaluation [1,2] and firing pin impressions [3,4], These have provided useful additional information to the forensic scientist. This investigation was conducted to further expand the applicability of the SEM and the developed imaging techniques for use on other forms of physical evidence. Specifically, striations on copper-jacketed bullets and contaminant particles recovered from personal articles (clothing, shoes, etc) were chosen.

Comparison of screwdriver tips to the resultant toolmarks

“…The 1970s saw research published that utilized SEMs to capture images of striated surfaces. 26,27,28,29 The nature of image collection in the SEM eliminated the challenge of features. SEMs are designed to produce high quality images, useful for reference and demonstrations in court.…”