Quasi-static Indentation Testing of Stainless Steel Wire Mesh Epoxy Laminated Composites

Abstract

This study presents the analysis of the quasi-static indentation behaviour of stainless steel wire mesh / epoxy laminate composites, with particular focus on their energy absorption characteristics and damage under impact conditions. The research explores the performance of composites reinforced with two grades of stainless-steel wire mesh, 304 and 316, with varying mesh sizes and wire diameters. The composites were fabricated using a hand lay-up technique in an open mould, ensuring consistent quality and reproducibility. The experimental setup for the quasi-static indentation tests was designed to measure the maximum indentation force, displacement at maximum force, total displacement, and energy absorbed at maximum indentation. The tests were conducted in accordance with ASTM standards, and the results were statistically analysed using Tukey’s pairwise comparisons to determine significant differences between the samples. The findings reveal that the A2 (304) composite, with its finer mesh size, exhibits the highest energy absorption capacity, making it a prime candidate for applications requiring lightweight and high-impact resistant materials. The study also compares the specific energy absorption (SEA) of the samples, which is the energy absorbed per unit mass, highlighting the superior performance of the A2 sample in this regard. Damage assessment was carried out by capturing images of the front and back surfaces of the indented laminates and analysing them using ImageJ. The damage patterns, including matrix cracking, bulging, wire shearing and wire breakage, were observed and quantified. The 304-grade wire mesh composite showed larger damage areas as compared to the 316-grade composite, suggesting differences in the materials' ability to resist crack propagation and deformation under stress. The study concludes that the composition of the wire mesh, particularly the presence of molybdenum in the 316 grades, contributes to its lower deformation rate and higher resistance to crack propagation. The comprehensive analysis of the composites' impact behaviour provides valuable insights into the design and selection of materials for safety-critical applications where energy absorption and damage tolerance are important.