Research on the preparation, mechanical properties, and applications of damage-sensing composite materials

TY - JOUR

T1 - Research on the preparation, mechanical properties, and applications of damage-sensing composite materials

AU - Wang, Yang

AU - Bao, Jiawei

AU - Zhang, Yanjun

AU - Wang, Yangwei

AU - Liu, Yuanpei

AU - Cheng, Xingwang

N1 - Publisher Copyright: © 2026 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.

PY - 2026/3

Y1 - 2026/3

N2 - Structural health monitoring is a well-established field for carbon fiber composites, a class of materials prevalent in ballistic protection systems. However, real-time damage monitoring within bulletproof structures remains largely unexplored. This study used gallium-indium liquid metal, which possessed fluidity and high conductivity, to fabricate flexible sensing material and explore its potential application on bulletproof plates. The relationship between microstructural deformation of the sensors and their electrical response under low-velocity impact loading conditions still remains unclear. The gallium-indium liquid metal flexible sensors were fabricated by the flexible electronic printing equipment. The mechanical and electrical responses of the sensors under quasi-static and dynamic loading conditions were investigated, and the microstructural evolution and failure mechanisms of the liquid-metal traces under different deformation and failure modes were analyzed. This work designed damage sensing grids and combined them with ultra-high molecular weight polyethylene plates to validate the damage localization functionality. The results showed that the liquid metal flexible sensor exhibited a wide strain range (up to 60%), excellent repeatability (the resistance amplitude remained stable after 500 cycles of repeated loading), and a significant piezoresistive effect under bending and low-velocity impact. Additionally, the failure modes of the sensor under tensile, bending, and impact conditions were also investigated. These failures obstructed current flow, leading to increased resistance or even circuit breakage. The fabricated damage-sensing composite device demonstrated damage localization within a spatial range of (±2 mm) × (±2 mm), with successful trials/total trials = 4/5.

AB - Structural health monitoring is a well-established field for carbon fiber composites, a class of materials prevalent in ballistic protection systems. However, real-time damage monitoring within bulletproof structures remains largely unexplored. This study used gallium-indium liquid metal, which possessed fluidity and high conductivity, to fabricate flexible sensing material and explore its potential application on bulletproof plates. The relationship between microstructural deformation of the sensors and their electrical response under low-velocity impact loading conditions still remains unclear. The gallium-indium liquid metal flexible sensors were fabricated by the flexible electronic printing equipment. The mechanical and electrical responses of the sensors under quasi-static and dynamic loading conditions were investigated, and the microstructural evolution and failure mechanisms of the liquid-metal traces under different deformation and failure modes were analyzed. This work designed damage sensing grids and combined them with ultra-high molecular weight polyethylene plates to validate the damage localization functionality. The results showed that the liquid metal flexible sensor exhibited a wide strain range (up to 60%), excellent repeatability (the resistance amplitude remained stable after 500 cycles of repeated loading), and a significant piezoresistive effect under bending and low-velocity impact. Additionally, the failure modes of the sensor under tensile, bending, and impact conditions were also investigated. These failures obstructed current flow, leading to increased resistance or even circuit breakage. The fabricated damage-sensing composite device demonstrated damage localization within a spatial range of (±2 mm) × (±2 mm), with successful trials/total trials = 4/5.

KW - damage sensing

KW - electromechanical response

KW - gallium-indium liquid metal

UR - https://www.scopus.com/pages/publications/105034486925

U2 - 10.1088/1361-665X/ae4b79

DO - 10.1088/1361-665X/ae4b79

M3 - Article

AN - SCOPUS:105034486925

SN - 0964-1726

VL - 35

JO - Smart Materials and Structures

JF - Smart Materials and Structures

IS - 3

M1 - 035017

ER -