Theses and Dissertations
Advisor
Stone, Tonya W.
Committee Member
Dickel, Doyl
Committee Member
Woodson, Stanley
Committee Member
Peterson, Luke
Date of Degree
5-16-2025
Original embargo terms
Embargo 2 years
Document Type
Dissertation - Open Access
Major
Engineering (Mechanical Engineering)
Degree Name
Doctor of Philosophy (Ph.D.)
College
James Worth Bagley College of Engineering
Department
Michael W. Hall School of Mechanical Engineering
Abstract
The increased lethality of recently fielded anti-personnel projectiles mandates an escalation in personal armor performance. Concurrent advancements in ceramic technologies have allowed designers to incorporate harder but more brittle materials into hard armor designs to defeat yet more capable penetrating projectiles. Understanding the failure mechanics of such materials is vital to ensuring adequate performance in real-world conditions. By using modern technology to exploit favorable properties in armor materials, their protective capabilities may be improved. Preliminary testing of that premise was conducted in this experimental work. The first study examined the cracking properties of silicon carbide armor ceramic when impacted by an armor-piercing bullet to understand the physics involved when ceramic armor encounters a penetrating projectile. We utilized X-ray imaging and scanning electron microscopy to characterize the cracking patterns in armor. In the next study, we examined six boron carbide/silicon carbide hybrid body armor plates which were impacted by a standard 0.30-caliber M2AP (armor-piercing) bullet. This allowed examination of the failure modes and performance of the ceramic plates when backed by 32 layers of unadhered Kevlar KM2 woven aramid. The lack of adhered ballistic backer composite was intended to isolate the ceramic crack patterns from outside influence. Pre-etched crack patterns in both front and back sides of the armor appeared to guide crack propagation, indicating a novel direction for future study. The last experimental study was aimed at confirming the prior results in a more representative armor condition. As such, eight boron carbide armor plates with 55 layers of Kevlar KM2+ aramid fabric bonded to the rear of the ceramic, were impacted by a standard 5.56mm NATO M855 round. Laser etching of crack patterns into fully built ceramic armor was shown by statistical analysis to guide the paths of crack propagation in the ceramic when struck by a projectile without a reduction in single hit performance.
Recommended Citation
Fridlund, Jason Taylor, "An investigation of ultra-short pulsed laser processing for novel improvement of body armor performance" (2025). Theses and Dissertations. 6486.
https://scholarsjunction.msstate.edu/td/6486
