Ballistic helmets – Their design, materials, and performance against traumatic brain injury

Abstract

a b s t r a c tProtecting a soldier's head from injury is critical to function and survivability. Traditionally, combat helmets have been utilized to provide protection against shrapnel and ballistic threats, which have reduced head injuries and fatalities. However, home-made bombs or improvised explosive devices (IEDs) have been increasingly used in theatre of operations since the Iraq and Afghanistan conflicts. Traumatic brain injury (TBI), particularly blast-induced TBI, which is typically not accompanied by external body injuries, is becoming prevalent among injured soldiers. The responses of personal protective equipment, especially combat helmets, to blast events are relatively unknown. There is an urgent need to develop head protection systems with blast protection/mitigation capabilities in addition to ballistic protection. Modern military operations, ammunitions, and technology driven war tactics require a lightweight headgear that integrates protection mechanisms (against ballistics, blasts, heat, and noise), sensors, night vision devices, and laser range finders into a single system. The current article provides a comparative study on the design, materials, and ballistic and blast performance of the combat helmets used by the US Army based on a comprehensive and critical review of existing studies. Mechanisms of ballistic energy absorption, effects of helmet curvatures on ballistic performance, and performance measures of helmets are discussed. Properties of current helmet materials (including Kevlar Ò K29, K129 fibers and thermoset resins) and future candidate materials for helmets (such as nano-composites and thermoplastic polymers) are elaborated. Also, available experimental and computational studies on blast-induced TBI are examined, and constitutive models developed for brain tissues are reviewed. Finally, the effectiveness of current combat helmets against TBI is analyzed along with possible avenues for future research.

Shear strength and fracture toughness of carbon fibre/epoxy interface: effect of surface treatment

“…Such composites exhibit high structural stability, excellent damage tolerance and energy absorption due to the yarn interlacing. In an impact event the kinetic energy is dissipated through a number of mechanisms, including deformation of secondary yarns, primary yarn breakage and energy spent to overcome inter-yarn friction [2]. The ease of incorporating different types of yarns enables one to manufacture composites with a wide range mechanical and physical property.…”

Camouflage design and head measurement characteristic of Indonesian armoured vehicle helmet

“…In the early 1960s developed the technology is more lightweight and comfortable [1]. Therefor helmet priority to protect the head from level II protection specifically resistant from beating, bump, collision from sharp, hard object, and shrapnel.…”

“…Up the time of WWI (World War I) and WWII soldiers use a helmet made of steel [1]. Ancient thought that military helmet must be resistant to various types of various types of assaults, penetration distances involve helmet made from iron/steel impacting helmet very heavy weights.…”

“…Therefor helmet priority to protect the head from level II protection specifically resistant from beating, bump, collision from sharp, hard object, and shrapnel. Accordingly, a helmet made from KEVLAR Aramid and epoxy resin that lighter than steel [1]. Material changes from metal in WWI, WWII into composite kevlar is PASGT (Personnel Armor System for Ground Troops) and the MICH (Modular Integrated Communications Helmet) for SOF (Special Operations Force).…”

Experimental Evaluation of the Impact Strength of Laminated Composites with a Thermoplastic Matrix

“…Most commonly used for manufacturing ballistic composites are aramid fibers (RUSLAN ® -SVM, Kevlar ® , Twaron ® , Rusar ® , Teksar ® ), ultra-high molecular polyethylene fibers (UHMPE), such as Dyneema ® , Spectra ® , glass and carbon fibers [2][3][4][5][6]. Composite materials, based on PBO (Zylon ® ), basalt and organic fibers, are less common, as later are relatively less strong [7], and PBO fibers have a tendency to aging, that can lead to sharp decreasing of ballistic features [5].…”