Geopolymer based composites as emerging materials for protective and ballistic applications: a comprehensive review

Abstract

Geopolymers are an emerging class of inorganic binders with considerable potential for use in protective and impact-resistant systems. Their ceramic-like microstructure, high thermal stability, compositional tunability, and relatively low density make them promising alternatives or complements to conventional armor materials such as technical ceramics, high-performance concretes, and metallic composites. Despite extensive research on geopolymers in construction and materials engineering, their application in ballistic and protective systems remains insufficiently explored and fragmented. This systematic review summarizes recent studies on geopolymer and geopolymer-based composite materials for protective applications, focusing on mechanical performance, dynamic and impact resistance, failure mechanisms, and energy absorption. Both monolithic geopolymers and hybrid multilayer systems are discussed, where geopolymers serve as load-bearing, protective, or binding layers. The influence of material composition, porosity, fiber reinforcement, and functional additives on ballistic response is addressed. The review also highlights civil and dual-use applications, including blast-resistant structures and critical infrastructure protection, and discusses sustainability aspects related to the use of industrial by-products and reduced carbon footprint. Key research gaps and future directions for advancing geopolymer-based protective systems are identified.