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• Key developments in dynamic testing techniques of yarns and fabrics are summarized. • Gripping fibers effectively is essential in dynamic tensile tests. • The morphology of a yarn affects its transverse deformation behavior. • Polymer spray coating is a method for improving fabric penetration resistance. • Current challenges and future research directions are discussed. This mini review provides a succinct overview of dynamic mechanical tests for woven fabrics and ballistic fibers, which are widely used for penetration-resistant applications. Considering the structural hierarchy of woven fabrics, this work highlights recent studies at different scales, encompassing uniaxial tensile tests and transverse impact tests of yarns, yarn pull-out tests from fabrics, and transverse impact tests of fabrics. The dynamic characterization techniques employed in these tests are discussed, along with the associated challenges. This paper serves as a quick guide for those seeking to gain insights into the dynamic behavior of woven fabrics. [ABSTRACT FROM AUTHOR]

This paper presents the details of experimental work on characterising the tensile properties of UHMWPE (Spectra® 1000) single yarns at different strain rates from 3.3 × 10−5 to 400/s. According to the measured stress–strain curves, there was a transition from ductile to brittle behaviour as the strain rate increased from 3.3 × 10−5 to 0.33/s; the tensile properties were highly sensitive to strain rate in this range. Specifically, the tensile strength and Young's modulus increased distinctly with increasing strain rate while the failure strain and toughness decreased. However, these tensile properties were not dependent on strain rate over the range from 0.33 to 400/s. The results showed that the measured tensile strength, failure strain and Young's modulus were independent of the tested gauge lengths (25 and 50 mm). Moreover, yarn type (warp and weft) had a noticeable effect on tensile strength, but the effect of yarn type on failure strain and Young's modulus was negligible. The microscopic examination of fractured fibres' ends revealed that fibrillation and axial splitting were the dominant fracture modes at low strain rates, while the fibres failed in a more brittle manner with little fibrillation at high strain rates. [ABSTRACT FROM AUTHOR]

This paper reports a method to construct the complete constitutive model of carbon fiber‐reinforced plastic (CFRP) by distinguishing the strain rate state and modifying the material stiffness. In quasistatic (low strain rate) compression, the initial nonlinear effect caused by the material defects was described by introducing an nonlinear increasing factor. In dynamic (high strain rate) impact, the nonlinear strengthening effect was described by introducing the dynamic amplification factors of stress and strain based on the reference state. Considering the instantaneous temperature rise obtained from the impact work–temperature generation equation and the influence of temperature on modulus and strength, the coupled thermomechanical constitutive models combining the strain rate effect and the temperature effect were established. The user‐defined material subroutines (VUMAT) were developed, and then these constitutive models were verified by finite element analysis (FEA). Finally, the developed material subroutine was applied to predict the impact penetration of CFRP laminates, and the results show that the opening holes, damage and energy dissipation are in good agreement with the reference experiment. This work comprehensively analyzed the construction method of CFRP constitutive models, which would provide a guidance for the coupled thermomechanical behavior under dynamic impact. Highlights: An anisotropic continuum mechanical constitutive behavior considering strain rate effect and damage evolution behavior was established.A macroscopic anisotropic constitutive model including the coupled impact temperature generation‐mechanical behavior was established.Combined with the incremental finite element method, the three‐dimensional user‐defined material subroutines (VUMAT) were developed and verified.The thermomechanical impact penetration behaviors of CFRP laminates was predicted, and the stress field, temperature field and failure characteristics were visualized. [ABSTRACT FROM AUTHOR]

• UHMWPE yarns are highly sensitive to strain rate at low rates of deformation. • There is a threshold for strain rate above which strain rate effect is negligible. • Plain weave fabrics have better impact performance than satin weave fabrics. • Spherical projectile penetrates UHMWPE fabrics by a 'wedge-through' mechanism. • A mesoscopic modelling approach of woven fabrics at the yarn level is proposed. A comprehensive study on the impact behaviour of UHMWPE woven fabrics is presented in this paper, which consists of four parts: geometric measurement of fabric parameters, tensile testing of constituent yarns, impact testing of fabrics, and numerical modelling of fabrics subjected to impact loading. Two fabric materials, i.e. a plain weave fabric made of SpectraⓇ 1000 fibres and a 4-harness satin weave fabric made of DyneemaⓇ SK75 fibres, were examined. Firstly, the geometric features of fabrics, such as yarn cross-sections and weave profiles, were characterised via microscopic analysis. Then the tensile properties of single yarns at different strain rates were measured, and results showed that UHMWPE yarns are highly sensitive to strain rate at very low loading rates. Tensile strength as well as longitudinal modulus showed a noticeable increase, whereas failure strain and toughness decreased with the increase of strain rate. However, these properties remained nearly constant in the strain rate range from 0.33 to 400 s−1. Furthermore, projectile impact tests were conducted on single-ply and multi-ply fabric targets under different impact velocities. The energy absorption characteristics, perforation mechanism, and yarn pull-out behaviour were analysed. Finally, finite element models of the fabrics were developed based on the measured geometric parameters and tensile properties of constituent yarns. The models were able to accurately simulate the impact response of the fabrics studied. The insights gained from this investigation will facilitate the effective utilisation of UHMWPE fabrics in armour and other protective applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Woven wire mesh is a metallic fabric outperforming traditional metal sheets in air circulation, weight saving, impact resistance, etc. In this study, the dynamic mechanical response of steel wire mesh subjected to low-velocity impact loading was investigated using both experimental and numerical methods. An instrumented drop-weight impact facility was used for experimental impact tests, with the effects of clamping wire direction, impact energy, impactor's mass and size being considered. The extents of damage to the wire mesh specimens under different loading conditions were evaluated after impact tests. Three types of contact force vs. displacement curves corresponding to the plastic deformation, wire breakage, and perforation of wire mesh were identified. Weft wires were found to be stronger and stiffer than warp wires because they could resist higher peak forces and experienced smaller maximum displacements under the same impact energies. The experimental results revealed that the peak contact force increased with impact energy until wire breakage occurred, after which the peak force remained almost unchanged. With the increase of impactor mass, wire mesh specimens experienced severer damage due to the inertia effect and strain rate effect. Impactor size had a significant influence on the dynamic response of wire mesh; a great increase in peak contact force was found when using a larger impactor tip. Moreover, a mesoscale finite element model was developed to analyse the propagation of stress and the evolution of dynamic failure in wire mesh during impact. The simulation results showed that more than 80% of the impactor's kinetic energy was absorbed through the deformation and failure of wire mesh, while the frictional energy dissipation accounted for about 10% of impact energy. • Three types of contact force vs. displacement curves of wire mesh were identified. • Weft wires could resist higher force corresponding to wire breakage than warp ones. • Wire mesh material behaved in a membrane stretching mode under low-velocity impact. • Impact-induced stress propagated in an orthotropic manner in wire mesh. • More than 80% of impact energy was absorbed as the internal energy of wire mesh. [ABSTRACT FROM AUTHOR]

Microstructural changes and ferrite phase transformation under shock loading, between 8.5 GPa and 17.5 GPa, in a hot-rolled Lean Duplex Stainless Steel (commercially known as LDX 2101) were investigated in as-received and pre-deformed conditions. The latter condition was considered to distinguish classical deformation twins at high strain rates from those associated to the reversible ferrite phase transformation. Plate impact experiments were used to introduce compressive shock loading at peak stresses below and above the stress threshold of the ferrite phase transformation, 13 GPa. Effects of shock loading were also examined by compressing shocked samples quasi-statically and comparing their response with those tested in the as-received condition. The microstructural examinations revealed that the ferrite in LDX 2101 experienced a reversible phase transformation at a peak stress of ~17 GPa. The fingerprints for this transformation were {112}<111> primary twins and {332}<113> primary and secondary twins. In addition, the yield stress of the sample pre-shocked at ~17 GPa showed a considerable increase (⁓150 MPa) compared to the flow stress in as-received conditions. [ABSTRACT FROM AUTHOR]

This work studied the mechanical response and the associated microstructures and failure mechanisms of additively manufactured Ti matrix composites with in-situ synthesised Ti 2 Ni and TiC x reinforcements under a variety of loading rates. The composites were fabricated using directed energy deposition technique with Ti–6Al–4V (Ti64) and Ni coated graphite (NCG) powders. Different proportions of Ti64 and NCG were mixed to manufacture the specimens with different compositions. Compression tests were conducted at strain rates in the range of 10−3 to 800 s−1. Our results show that the metallurgical and mechanical properties of the composites change with the NCG fraction. The failure mechanisms of the composites are a combination of tensile fracture of brittle TiC x precipitates and shear of the Ti matrix. The composites with higher NCG content exhibit increased strength, reduced ductility and less strain rate sensitivity. Under high strain rate compression loading, the Ti–Ni–C composite can provide enhanced strength with the ductility unchanged, which make it a prospective material for the applications subjected to impact loads. [ABSTRACT FROM AUTHOR]