Rheological and Energy Absorption Properties of Backing Materials for Measurement of Behind Armour Blunt Trauma

Abstract

Behind Armour Blunt Trauma (BABT) is the impact experienced by the body wearing armour, when subjected to a non-penetrating projectile. BABT is measured by the indentation of armour (Back Face Signature or BFS) on a backing material made of soft clay. The clay is considered to be tissue simulant which provides a correlation between BFS and BABT. The correlation depends critically on the choice of backing material, loading conditions, and its history. The applicability of clay as a tissue simulant to measure BABT is not straightforward as the viscoelastic response of human tissue and clay are different. Different materials can give different responses based on their viscoelastic properties. This paper describes the thermo-rheological and energy absorption studies conducted at Terminal Ballistics Research Laboratory, Chandigarh on two different backing materials. The study was conducted to find the differences in viscoelastic behavior and the subsequent differences in BABT.