Assessment and quantification of ballistic impact damage of a single-layer woven fabric composite

Abstract

A methodology is developed to visually analyze and quantify macroscale and mesoscale impact damage on a single layer of S-2 glass/SC15 toughened epoxy plain weave composite. Specimens were clamped in a 203 mm diameter circular frame and impacted by a 5.5 mm (0.22 caliber) right circular cylindrical steel projectile at impact velocities ranging from 104 to 472 m/s. High-resolution images were obtained at the point of impact and up to the edge of the circular frame using an 80 MP camera. Three types of mesoscale damage were identified: (i) transverse tow cracks, (ii) tow–tow delamination, and (iii) 45° matrix cracks. A MATLAB program was developed to translate the image data into a digital damage map whereby the output of color intensity correlated with the quantity and type of material damage. Digital maps generated for select specimens revealed that characteristic damage patterns arise for woven fabric composites including a diamond pattern in matrix cracking and a cross pattern in tow–tow delamination. The greatest extent of matrix cracks and tow–tow delamination over any specimen was observed for the projectile impact with initial velocity of 174 m/s, which is very close to the calculated ballistic limit velocity of 175 m/s.

Toward automated identification and quantification of meso-scale damage modes in plain weave glass/epoxy composite laminates

“…Single-layer, plain weave, S-2 glass/SC15 epoxy composite panels were manufactured and ballistically tested at the US Army Research Laboratory in Aberdeen, MD, USA (Bonyi et al, 2019;Meyer et al, 2018). Composites were manufactured from 24 oz plain weave fabric woven from AGY 463-AA-250 weight S-2 glass roving and Kaneka Aerospace (then Applied Poleramic) SC-15 toughed epoxy using the vacuum assisted resin transfer molding (VARTM) process.…”

“…A methodology was recently developed to characterize, analyze, and quantify mesoscale damage in ballistic impacted glass/epoxy composites (Bonyi et al, 2019). This methodology manually determined the spatial distribution and quantity of mesoscale damage modes (transverse cracks, 45 matrix cracks, and tow-tow delamination) from backlit, high-resolution images of the post-experiment, impacted targets.…”

“…To minimize human error, manually counted damage was verified by three different users, each counting three different times. The reader is referred to the prior work for additional detail (Bonyi et al, 2019). In the present work, this manual method is used as a baseline to evaluate the accuracy of the three automated methods described in this paper.…”

Ballistic penetration damages and energy absorptions of stacked cross-plied composite fabrics and laminated panels

“…Compared with steels, the aramid fabrics have a high ratio of ballistic performance/weight ratio (Laha and Majumdar, 2016). Many methods for designing high-performance bulletproof materials have been developed from structure optimizations and materials hybrid (Bonyi et al., 2019; Patil and Naik, 2018; Song et al., 2018). The energy absorption mechanisms include friction among yarns, yarn breakage, and fabric deformation (Budadin et al., 2019; Hwang et al., 2015; Xu et al., 2018).…”

Evaluating impact damage to fabric-based personal armor by infrared NDT

“…Analyzing a dynamic temperature response of materials toward a DA impact seems to be promising for assessing the quality of armor protection, particularly by means of infrared (IR) thermographic nondestructive testing (Bonyi et al., 2018; Gay et al., 2017; Russian National Standard # P 50744-1995, 1995; Russian National Standard # P 55623-2013, 2013; Shim et al., 2012; Vavilov, 2014; Vavilov et al., 2015; Xu et al., 2018). It is believed that, in the future, such temperature-related data, being combined with results of other tests, will allow predicting the reliability of armor protection.…”