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The effectiveness of cardiovascular stenting procedure depends on the crimping and expansion characteristics of a stent, influenced by its design parameters. In this study, CoCr stents are fabricated, crimped on a tri-folded balloon, and expanded using manual inflation device. Similarly, in the finite element model, a tri-folded balloon is used to expand the stent. The length and diameter are measured to evaluate the radial strength, recoil, foreshortening, and dogboning. The simulation and experimental results match satisfactorily. The validated FE model can be used with confidence to optimize future stent designs, thus reducing the number of testing and product development time. [ABSTRACT FROM AUTHOR]

Microcellular injection molding (MIM) of thermoplastics is a challenging molding process compared to conventional injection molding (IM) process because of its narrow processing window. As far as microcellular molding of open-celled foam is concerned, it is much more difficult because of extremely narrow processing window for open-cell foam and transient nature of melt temperature and pressure inside cavity during the molding process. However, it is expected that molding of open-celled microcellular foam may open many new areas such as tissue engineering, drug delivery, reverse osmosis, dialysis membranes, and fuel cell. The production cost may also be reduced manifolds. In present work a novel expandable cavity mold (EC mold) was designed and fabricated. EC mold has some nonconventional features like pneumatically actuated gate seal, mechanism for cavity expansion, and arrangement for cyclic heating-cooling of core and cavity blocks. In present study polylactic acid (PLA), a biodegradable polymer, was used and expandable cavity molding (EC molding) variables, namely, cavity expansion rare (mm/s), cavity expansion distance (mm), and cavity expansion-compression-expansion (ECE) profile mode, were studied. The results confirm molding of PLA foams with very high cell density and impinged structure. The micrographs and open-cell ratio confirm the formation of PLA foam with ~40% open-cell content. [ABSTRACT FROM AUTHOR]

The use of the porous Polylactic acid (PLA) for tissue engineering has gained the attention of the researchers worldwide. In this work, PLA tubes were extruded using CO 2 as a foaming agent. The foaming of the PLA tubes at various extruder screw rotational speed and different CO 2 pressure are studied in this work. Subsequently, morphological characterization and surface hydrophilicity studies of the tubes were carried out. It is be found that with an increase in the screw rpm, the contact angle first decreases and reaches the lowest value and then increase with the increase in screw rpm. Similarly, the effects of screw rpm and gas pressure on cross-sectional morphology and FTIR spectra were observed indicating an increase in crystallinity. [ABSTRACT FROM AUTHOR]

The monomer of poly(lactide), i.e. lactic acid is an optically active compound and thus renders optical activity in the polymer itself. In the present studies highly crystalline and low crystalline grades of poly(lactide) were used to prepare blends with different d- and l-ratios to explore the relation between d- and l-content and various properties of poly(lactide). Optical rotation was measured by Polarimetry to analyse d-content in the blends which was found to vary from 0.05 to 4.14 %. Polarized light microscopy revealed that both the growth rate and final average size of the spherulites increased with the decrease of d-content. The crystallinity was measured by differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD) methods. It was noticed that a small change in d-content produced remarkable changes in crystallinity and other properties of the blends. The mechanical properties were slightly modified with the decrease in d-content. [ABSTRACT FROM AUTHOR]

In this study, influence of blowing agent residence conditions on foam attributes has been investigated in extrusion foaming process. The blowing agent injection location in the extrusion barrel was found to affect the residence time inside the barrel, which in turn significantly transformed the foam microstructure. The injection location providing higher gas residence time resulted in foams with lower cell size, higher expansion ratio, and enhanced cell density. Further studies were performed to analyze the synergistic influence of residence time variation on foam attributes at different screw rotational speeds, die temperatures, and blowing agent contents. [ABSTRACT FROM PUBLISHER]

Magnesium and its alloys are getting more attention in the field of tissue engineering as it is biodegradable as well as biocompatible. An open cell structure in particular offers the advantage of body fluid transportation through it and allows the growth of new tissues. Open cell Mg foams with pore interconnectivity are difficult to fabricate from conventional techniques. In the present work, a novel approach has been successfully developed to fabricate the open cell Mg structures with pore interconnectivity using powder metallurgy route and Ti-woven wire mesh as a space holding material. Pore morphology and percentage porosity can be easily altered by adjusting the Ti-wire diameter and shape of construct. Ti-woven wire mesh in the shape of netted wire gave the best result in terms of homogeneity of pores and strength. Maximum porosity achieved is 60% and ultimate tensile strength is measured to be 78 MPa for the porous structure. [ABSTRACT FROM AUTHOR]

In this study, the influence of field distribution of ultrasonic waves on the manufacturing of microcellular Acrylonitrile-Butadiene-Styrene (ABS) foam was investigated. In the primary studies, Aluminum foil erosion tests were performed to analyze the spatial field distribution of ultrasonic waves throughout the water bath. It was found that there exists a critical effective distance from the ultrasonic transducer where the maximum cavitation intensity can be achieved. Prior to and beyond this critical effective distance, the cavitation intensity reduces drastically. In the succeeding study, gas saturated polymer pellets were placed inside the ultrasound medium at various effective distances from the transducer for a predefined amount of treatment time and then were microcellular solid-state batch foamed. Intense cell nucleation phenomenon was observed in samples sonicated at the critical effective distance, while at other distances a very mild increment in cell density was observed. The expansion ratio and cell morphology was also found to be significantly affected by the relative placement of gas- saturated polymer with respect to the transducer in sonication medium. [ABSTRACT FROM AUTHOR]

Despite its relevance for law enforcement applications, the design of soft armor has mainly been based on a trial-and-error approach. In this paper, a combined experimental, machine learning, and finite element analysis framework is used to build a predictive numerical model for the analysis and hence, design of soft armor. The material models for major components of the soft armor certification system--bullet, shoot pack, straps, and clay backing, are first constructed using laboratory tests and publicly available data. Next, three metrics, namely, back face signature (BFS), number of penetrated shoot-pack layers, and mushrooming of the bullet are established to gauge the model's accuracy with respect to the laboratory ballistic test data. A machine learning (ML) model is used as a surrogate to predict the BFS and the number of eroded elements. Finally, optimized material model parameters are obtained through ML-based surrogate model and Bayesian optimization algorithm. The final validation of the developed framework is carried out using laboratory ballistic test data involving multiple shots on the shoot pack. The results indicate that reliable predictive data can be obtained using the developed process, and likely, can be extended for use in modeling other impact simulations. [ABSTRACT FROM AUTHOR]

In the present research, glass and basalt fiber-reinforced polypropylene composites' behaviour in quasi-static and dynamic conditions is studied. Composites were fabricated by vacuum assisted Compression molding method. Composites failure under quasi-static tension and compressive conditions was studied along with its failure behaviour under low-velocity impact and super-sonic shock loading under dynamic conditions. The study results showed that basalt fiber-reinforced polypropylene (Basalt/PP) composite's tensile and compressive strength is higher than glass fiber-reinforced polypropylene (Glass/PP). The Basalt/PP showed no penetration against low velocity impact (LVI) with negligible deformations till 50 J. However, the Glass/PP perforated at 50 J with various failure patterns occurring at back side. The fiber-matrix interface adhesion plays an important role in super-sonic shock loading by absorbing shock wave energy due to ductile nature of polypropylene and the two composites absorbed energy via matrix and fibers failure, no brittle failure of laminates occurred under shock loading. [ABSTRACT FROM AUTHOR]

All bioresorbable polymeric implants are radiolucent, making them undetectable under the X-rays. Therefore, to improve their X-ray visibility, the high effective atomic number (Zeff) material such as Pt, Au, Ta, Ba, or its alloy are attached to the body of the bioresorbable implant. However, during the in vivo degradation, these bio-inert heavy metals can either detach or leach out from the lesion site and accumulate into the vital organ, leading to severe health complications. Thus, as a strategy, the novel biodegradable and radiopaque Mg alloy was produced to impart X-ray visibility in the biopolymer. Here, the Mg was alloyed with the optimized ratio of heavy metals, i.e., Zn and Y. The radiopaque Mg alloy was characterized and powdered to the size of 25–20 µm. Further, it was blended with radiolucent Poly-L-lactic acid (PLLA) and polycaprolactone (PCL) polymer. The Bi-axially expanded (BAE) tubes of PLLA/PCL and PLLA/PCL/Mg alloy (5% wt.) were extruded for fabricating cardiovascular stents. The BAE tube comparison studies were performed for thermal stability, wettability, surface roughness, and mechanical properties. The potential of 5% Mg alloy in the polymeric matrix was evaluated as a nucleating, reinforcing, and radiopaque agent. In vitro accelerated degradation study was performed in the physiological fluid to evaluate the pH variation and decomposition rate. Finally, in vitro biocompatibility was assessed by evaluating the behavior of L929 fibroblast cells, followed by the blood biocompatibility test on the blends. [ABSTRACT FROM AUTHOR]

In this study, the effect of high strain rate on the dynamic mechanical properties of shear thickening fluid (STF) impregnated felt of ultra‐high molecular weight polyethylene (UHMWPE) was investigated by split‐hopkinson pressure bar. UHMWPE felts are randomly oriented nonwoven fabric that holds each other due to inter‐fiber coupling either by thermal calendaring or mechanical entanglement. Its lower areal density and highly porous structure can be utilized in lightweight ballistic resistance material. The junction points inside its porous structure make it easier to hold abundant STF. Shear thickening fluid was prepared by dispersing 100 nm dry silica powder into polypropylene glycol at 67.5 wt% concentration using probe ultrasonicator at 25°C. Rheological characterization of prepared STF was conducted using MCR702 advanced Anton Paar rheometer. It was done by performing a steady shear rate and thixotropy tests for shear thickening and structural regeneration behavior. In‐house fabricated split‐hopkinson pressure bar setup was used to evaluate dynamic compressive behavior at different strain rates by changing triggering pressure. It was found that STF impregnated felt shows a higher amplitude of strain rate augmentation and energy absorption than a neat felt. The impact energy absorption increases with increasing strain rate. However, the peak stress shows an opposite trend with an increased strain rate in STF impregnated felt. [ABSTRACT FROM AUTHOR]

Compressive behaviour of open and closed cell polyurethane foam samples under large deformation is studied using micro‐Computed Tomography (micro‐CT), Digital Volume Correlation (DVC) technique and micro‐Finite Element (micro‐FE) modelling. The micro‐CT images of the foam samples at different compression strains are used to determine anisotropy in the foams, to obtain qualitative information on deformation mechanisms, to quantify the deformation and strains using a local DVC approach and to generate images for micro‐FE modelling of the foam samples. Micro‐FE modelling predicts the deformation using an elastoplastic material model coupled with continuum damage mechanics. Two different types of boundary conditions, experimentally derived (ExBC) and interpolated from DVC (IPBC), were implemented to evaluate the displacements in the micro‐FE models. A reduced integration scheme in micro‐FE analysis resulted in high artificial energy and was discarded in favour of full integration. The displacement predicted by IPBC matched with DVC displacement contours for closed cell foam. The ExBC‐predicted axial displacement (W) showed a better agreement with DVC than transverse displacements (U, V) contours. However, a significant statistical comparison (R2 > 0.70) of all displacements was obtained for both IPBC and ExBC. For open cell foam, both boundary conditions predicted a significant difference in the displacement contours with respect to DVC measurements. Still, the axial displacements of ExBC and IPBC showed a better statistical significance (R2 > 0.70). [ABSTRACT FROM AUTHOR]

PLA and its blends are the most extensively used materials for various biomedical applications such as scaffolds, implants, and other medical devices. The most extensively used method for tubular scaffold fabrication is by using the extrusion process. However, PLA scaffolds show limitations such as low mechanical strength as compared to metallic scaffolds and inferior bioactivities, limiting their clinical application. Thus, in order to improve the mechanical properties of tubular scaffolds, they were biaxially expanded, wherein the bioactivity can be improved by surface modifications using UV treatment. However, detailed studies are needed to study the effect of UV irradiation on the surface properties of biaxially expanded scaffolds. In this work, tubular scaffolds were fabricated using a novel single-step biaxial expansion process, and the surface properties of the tubular scaffolds after different durations of UV irradiation were evaluated. The results show that changes in the surface wettability of scaffolds were observed after 2 min of UV exposure, and wettability increased with the increased duration of UV exposure. FTIR and XPS results were in conjunction and showed the formation of oxygen-rich functional groups with the increased UV irradiation of the surface. AFM showed increased surface roughness with the increase in UV duration. However, it was observed that scaffold crystallinity first increased and then decreased with the UV exposure. This study provides a new and detailed insight into the surface modification of the PLA scaffolds using UV exposure. [ABSTRACT FROM AUTHOR]

Material systems capable of handling both the ballistic impact and blast waves are necessary for security forces. In this study, the high strain rate performance of monolithic and bonded ultra‐high molecular weight polyethylene (UHMWPE) with high‐temperature resistant basalt/polyetherimide (B/PEI) composite is presented. Individual composite laminates were fabricated using vacuum‐assisted compression molding. Subsequently, cylindrical test coupons were cut using a high‐pressure waterjet. A suitable adhesive grade was used for the bonding of two different composite types. The dynamic compression studies were conducted on a split‐Hopkinson pressure bar (SHPB). For identical incident energies, the range of strain rates attained by monolithic UHMWPE, B/PEI and bonded composites differed significantly. Monolithic UHMWPE achieved the highest rates of loading, whereas higher stresses were recorded for the B/PEI composite. Yet, monolithic UHMWPE, owing to higher constant stress plastic flow, results in higher toughness. Bonded composites revealed hybrid properties with delamination of UHMWPE as the primary failure mode. High‐speed imaging exposed severe deformation of UHMWPE during dynamic compression. SEM micrographs revealed fiber pull‐out and deforming behavior of UHMWPE and brittle failure of B/PEI composite. B/PEI in a bonded composite system never failed under dynamic compression within the experimental range, thus providing a window of opportunity to tailor‐make better ballistic and blast protection materials. [ABSTRACT FROM AUTHOR]

High impact polystyrene sheets (HIPS) of 1.5 mm and 2.5 mm thicknesses were thermoformed on moulds of different parameters at sheet heating temperatures of 130℃ and 140℃. Formability studies indicated no difference in wall thickness distribution at different sheet temperatures. Due to non-uniform stretching of the sheet, wall thickness distribution along the slant length was found to have three regions. In the regions near the mould corner and clamp point, wall thickness was found to decrease with increase in distance from the corner, in these zones. The decrease near the corner was much greater and sharper than that near the clamp point. The decrease in both regions was found to increase at higher depths of draw and decrease at higher draft angles. In the intermediate portion of the slant length, no significant variation in wall thickness was observed. [ABSTRACT FROM AUTHOR]

An investigation of the effect of strain rate on the dynamic compressive behavior of glass/polytetrafluoroethylene (PTFE) composite is presented. Experimental studies were carried out on two dimensional (2D), satin weave (SW) and three dimensional (3D) woven glass/PTFE composites using split Hopkinson pressure bar (SHPB) apparatus. Commercial grades of glass/PTFE fabrics were autoclaved to prepare the composite laminates and circular specimens were cut out using a high‐pressure water jet. High strain rate studies confirmed the rate‐dependent behavior of all the woven composite systems under consideration. The highest rates of loading were attained by 3D woven specimens for identical incident energies. The highest peak stress attained by 3D woven specimens was 501 MPa, which was trailed by 2D woven specimens with 482 MPa stress. The advantage of satin weave was not reflected in the small specimens as the peak stress attained for identical loading was limited to 405 MPa. Similarly, the highest strain and toughness were recorded for 3D woven composites. However, the SW pattern unlocked a new possibility of controlling the primary damage axis. Furthermore, an analytical method is presented based on variable rate power law to predict the dynamic compressive stress of glass/PTFE. [ABSTRACT FROM AUTHOR]

The surface of dental implants plays a vital role in early and more predictable osseointegration. SLA (sandblasted large grit and acid-etched) represents the most widely accepted, long-term clinically proven surface. Primarily, dental implants are manufactured by either commercially pure titanium (CP-Ti) or Ti6Al4V ELI alloy. The acid etch behavior of CP-Ti is well known and its effects on the surface microstructure and physicochemical properties have been studied by various researchers in the past. However, there is a lack of studies showing the effect of acid etching parameters on the Ti6Al4V alloy surface. The requirement of the narrow diameter implants necessitates implant manufacturing from alloys due to their high mechanical properties. Hence, it is necessary to have an insight on the behavior of acid etching of the alloy surface as it might be different due to changed compositions and microstructure, which can further influence the osseointegration process. The present research was carried out to study the effect of acid etching parameters on Ti6Al4V ELI alloy surface properties and the optimization of process parameters to produce micro- and nanotopography on the dental implant surface. This study shows that the Ti6Al4V ELI alloy depicts an entirely different surface topography compared to CP-Ti. Moreover, the surface topography of the Ti6Al4V ELI alloy was also different when etching was done at room temperature compared to high temperature, which in turn affected the behavior of the cell on these surfaces. Both microns and nano-level topography were achieved through the optimized parameters of acid etching on Ti6Al4V ELI alloy dental implant surface along with improved roughness, hydrophilicity, and enhanced cytocompatibility. [ABSTRACT FROM AUTHOR]

The demand of high-speed wireless communication has increased, which need the data rate to be in the order of Terabyte per second (Tbps) in the near future. Terahertz (THz) band communication is a key wireless communication technology to satisfy this future demand. This would also reduce the spectrum scarcity and capacity limitation of current wireless systems. Microfabricated Folded Waveguide TWTs are the potential compact sources of wide band and high-power terahertz radiation. This study primarily focuses on machining technology for THz waveguide components requiring ultra-high precision micromachining. Rectangular waveguides, especially Folded Waveguides (FW), are even more difficult to manufacture using conventional machining techniques due to their small size and very tight tolerances. The criticalities in micromachining of FW for 0.22 THz have been addressed in this article. Half hard free cutting Brass IS 319-H2 was used as a work material due to its electrical and mechanical properties. Waveguide size of 0.852 × 0.12 mm was machined within ± 3–5 μm linear tolerances, surface roughness in the order of 45 nm Ra, and flatness less than half of wavelength (< λ/2). The split top and bottom blocks of the folded waveguide were aligned by dowel pins which matched within a tolerance of ± 5 μm. The perpendicularity and parallelism were maintained within 5 μm tolerance. This work explored and established the application of micromilling as reasonably suitable for the THz waveguides followed by ultrasonic cleaning as deburring. It also investigated the measured folded waveguide losses which were close to simulated values. [ABSTRACT FROM AUTHOR]

Kevlar reinforced composite material systems are widely used for personal body armors. Due to aging or minor damage while in service, body armor may get exposed to external weather conditions, including moisture. The present study investigates the effect of moisture on the high strain rate behavior of Kevlar/Polypropylene (K‐PP) composite. Flat K‐PP composite laminate was manufactured using a vacuum‐assisted compression molding followed by laser machining. Dynamic compressive loading tests were performed using split Hopkinson pressure bar setup. The phenomenological modeling approach was adopted to characterize the rate‐dependent behavior of dry and wet composites. For identical dynamic compressive loading, different strain rates, strains, and stresses were attained by the dry and wet composite specimens. Macroscopic and microscopic imaging was done to expose the variation in damage behavior as a function of moisture absorption. Significant property reduction as a function of moisture absorption emphasizes the need for moisture proofing and protecting the armor products from minor damages leading to sites for moisture ingress. [ABSTRACT FROM AUTHOR]

In this study, the influence of hybridization on the compression response of thermoplastic matrix-based composites under high strain rate loading was investigated. The intra-ply and inter-ply hybrid composites were manufactured with Kevlar/Basalt yarns as the reinforcements with Polypropylene as a matrix. Cylindrical composite specimens were laser cut from the flat compression moulded laminates. The composite specimens were loaded under high strain rate using split-Hopkinson pressure bar setup at strain rates ranging from 2815/s to 5481/s. The study revealed differences in the rate-dependent growth of peak stress, peak strain and toughness with the strain rate. Intra-ply hybrid composites with alternate weaving of Kevlar and basalt yarns exhibited highest peak stress as compared to the Inter-ply hybrid composites (alternate layers of Kevlar and basalt fabrics) and another intra-ply composite containing Kevlar in the warp and basalt in the weft direction. Whereas in inter-ply hybrid composite, with Kevlar as the loading face attained higher stress, while composite with Basalt as the loading face attained higher strain. SEM micrographs revealed that Kevlar on the loading face can bear the impact with lesser delamination as compared to the Basalt on the loading face. Damage studies revealed that Kevlar fiber surface loading results in higher stress as compared to basalt (brittle) surface loading with lower overall damage. • The influence of hybization on the high strain rate resposne of thermoplastic composites. • Intra-ply hybridization excels over inter-ply hybridization. • Placement and direction of yarns is crucial in intra-ply hybridization. • Higher areal density fabrics are replacable with hybrid fabrics of lower areal density. [ABSTRACT FROM AUTHOR]

The dynamic behaviour of the High Strength Low Alloy (HSLA) Steel before and after heat treatment was examined experimentally by performing quasi-static and high strain rate testing at room temperature and cryogenic temperatures. The high strain rate tensile testing of the material was performed on a Split Hopkinson Tensile Bar (SHTB) setup. A customized liquid nitrogen chamber equipped with UTM and SHTB was used to perform the cryogenic temperature testing. The stress–strain response of the material under different loading conditions was recorded and a modified Johnson–Cook material model was derived. It was observed that the flow stress of the material increased when tested at a high strain rate and it further increased at a cryogenic high strain rate loading environment. The microstructure of the material before and after heat treatment was also observed to identify the dominant phase change in microstructure contributing towards improvement in strength after heat treatment. The failure analysis of each category of the samples was examined under the Scanning Electron Microscope (SEM) after the testing. The formation of small and deep dimples for as-received samples and bigger and shallow dimples for heat-treated samples distinguished the type of failure between the quasi-static, high strain rate and cryogenic high strain rate material testing. • High Strength Low Alloy Steel (HSLA) were characterized at Quasi-Static and high strain rate tensile testing at room temperature and cryogenic temperature in both annealed and post heat treated conditions. • The customized Split Hopkinson Tensile Bar equipped with liquid nitrogen chamber and on-board temperature measurement system was developed to perform high strain rate cryogenic testing of HSLA steel. • The fractured surface of annealed and post heat treated samples were examined to understand the underlying effect contributing towards improvement in mechanical properties of the HSLA steel. • The modified Johnson–Cook material model parameters were derived based on the experimental results. The numerical simulations were performed to verify the developed constituent model. [ABSTRACT FROM AUTHOR]

Highlights • A novel single step biaxial expansion method is used for bioresorbable tube fabrication. • Biaxially expanded tubes have better radial compressive properties. • Brittle behaviour of PLA changes to ductile by addition of 5 wt% PCL. Abstract Bioresorbable stents is going to become the future modality for the treatment of coronary artery disease (CAD). However, the main limitation of the polymeric stent is its poor mechanical properties. For the proper functioning of a stent in the artery; it is required to enhance the radial stiffness of the polymeric stent. Polymeric tube manufacturing is the first and most important step in the stent manufacturing process. Usually, post processing operation which enhances the mechanical properties such as annealing, blowing and die drawing near glass transition are used after tube extrusion. In this study, along with conventional tube extrusion process (SE), a single step biaxial expansion method (BAE) was employed during the tube extrusion. The effect of manufacturing method on the radial compressive strength of the extruded tubes is thereby evaluated. For further determining the tubes radial resistive force, parallel plate crush testing as per ISO 25539-2 was performed and it is observed that tubes extruded by BAE method have better performance during crush testing as compared to the SE tubes of the same material. SEM was used for observing the cross-sectional morphology of the Cryo-fractured surface of fabricated bioresorbable tubes. [ABSTRACT FROM AUTHOR]

TITLE: A PROSPECTIVE STUDY OF ASSESSMENT OF BREAST ANTHROPOMETRY IN INDIAN BREAST CANCER PATIENTS INTRODUCTION: India has one of the youngest populations but there is a troubling trend of increasing breast cancer incidence. With increasing affluence, awareness and social demands, the demand for breast conservation surgery and standard of care has increased. Surgical options are guided by tumor, breast volume and patient factors. There is a difference between our population and the much studied west. In the current study, we tried to explore this hypothesis and tried to establish a baseline measurement of various anthropometric parameters of breast in Indian breast cancer patients. Further, we tried to categorise these parameters and attempted a correlation with breast conservation surgery, tumor and breast volume. MATERIALS AND METHODS: The study was done prospectively in 102 patients between January to October 2016. Anthropometric measurements of breast, nipple areola complex, ptosis and mammographic breast density of the normal breast were recorded. Breast volume was measured with a geometric method devised by Qiao et al. The measurements were done with the help of measuring tape, calipers and rulers and were categorized using quartiles. Tumor size and the surgery performed in these patients was also recorded. 70 patients were suitable for correlation of breast volume and tumor size. RESULTS: Mean breast volume in the study was 303 ml (93.25 - 1345 ml). Breast volume was divided into category I (<170ml), category II (170 - 360 ml) and Category III (>360 ml). Mean areola diameter, nipple diameter, nipple projection were 4.53 cm (2.3 - 8 cm), 0.99 cm (0.6 - 1.5cm) and 0.77 cm (0.3 - 1.5cm) respectively. 51 patients had grade 3 ptosis. Most common mammographic breast density is ACR II. BCS rate in category I was 17.64 percent while categories II and III had a BCS rates of 37.14 and 38.88 percent respectively. CONCLUSION: Breast measurements of Indian women are different from their western counterparts. Ptosis is seen more often. Geometric methods can be used to calculate breast volume and can help predict breast conservation rates and in patient referral. There is a paucity of literature on breast anthropometry in Indian breast cancer patients and this is one of the first studies to address it and its implications on surgery. [ABSTRACT FROM AUTHOR]

We consider a host of regular lattice architectures and present analytical and computational approaches to derive the structure-property relationship for such structured material by exploiting the translational periodicity of infinite lattices. Two specific geometries - the so-called hexagonal honeycomb and the woodpile lattice - are studied analytically and computationally. The elasto-plastic response in the case of the first, and the bending response of lattice beams for the second, is considered. These specific problems have been motivated by biostructures relevant to medical implants and scaffolds. We also present novel methods to additively manufacture such lattices. When possible, the response is obtained as an analytical function of the microstructural parameters described by the geometry of the repetitive elements of the lattice, such as characteristic diameter, length, or thickness. Alternative methods of manufacturing materials with random internal architectures are also presented. The relative strengths and weaknesses of the two classes of materials with respect to analysis and manufacture are discussed. [ABSTRACT FROM AUTHOR]

This paper presented an experimental and numerical investigation on the low velocity impact response of thermoplastic hybrid composites reinforced with Kevlar/basalt fabrics. Two hybrid and one Kevlar homogeneous composite laminates were manufactured with polypropylene as a resin. In the hybrid composites, one hybrid composite (H-1) was manufactured with alternate stacking of four layers of basalt and four layers of Kevlar and the second hybrid composite (H-2) was manufactured with four Kevlar layers on front face and four basalt layers on back face. Low velocity impact tests were performed using a drop-weight impact equipment at three different energies (25J, 50J and 75J). Among the two hybrid composites H-1 hybrid composite exhibited 15.58-20.79% and 13.47-20.47% improvement in the peak force and energy absorption, respectively, than the H-2 hybrid composite. The peak force and energy absorption of Kevlar homogeneous composite was also improved by 10.07-14.37% and 5.38-11.29%, respectively, due to hybridization. A three dimensional (3D) dynamic finite element software, Abaqus/Explicit, was implemented to simulate the experimental results of low velocity impact tests. A user-defined material subroutine (VUMAT) based on Chang-Chang linear-orthotropic damage model was implemented into the finite element code. The predictions from numerical simulation were found to be in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

As a major challenge, development of light-weight fibre reinforced polymer (FRP) composite body armour, characterization of candidate matrix polymers at high strain rate impact is the focus in this research. Polypropylene (PP) and the nano-composites with 1-5% by weight of NC (nanoclay) platelets are the candidates considered. In the characterization phase, high strain rate impact and quasi-static loading tests were performed to figure out the limiting (failure) responses. Comparison between the material systems is, subsequently, made to nominate one matrix configuration. Enhancements of mechanical properties with increase in weight percentage of the nanoparticles are observed at both quasi-static and dynamic loadings. Observations of dispersed imposed failure modes, development of novel model for failure modulus and evaluation of peak strength values are also attempted. [ABSTRACT FROM AUTHOR]

This study systematically investigates the effect of Shear Thickening Fluid (STF) treatment on the high strain rate properties of UHMWPE (Ultra High Molecular Weight Poly Ethylene) composites. Spherical nanosilica particles of size 100 nm were used for the synthesis of STF. The high strain rate impact studies were accomplished on in-house designed and fabricated Split Hopkinson Pressure Bar (SHPB) experimental set-up. Compression moulded UHMWPE variant Gold Shield ® was used as the ballistic composite. Both STF-treated as well as neat Gold Shield ® specimens were subjected to high strain rate impact testing. From the experimental results and Fractography studies it was revealed that STF treatment enhanced the ballistic resistance of Gold Shield ® composite material. In the SHPB experiments, the improved ballistic performance of STF-treated Gold Shield ® specimens was manifested in terms of higher peak stress, specimen strain rates and impact toughness. [ABSTRACT FROM AUTHOR]

Shear thickening fluids (STFs) are a special class of field responsive fluids which exhibit change of phase from liquid to solid when subjected to imposed shear. This remarkable characteristic of STFs has led to their application in soft body armor technologies, leading the development of concept of Liquid Body Armors (LBAs). LBAs extensively rely upon the symbiotic relationship between STF and high strength FRP (Fiber Reinforced Polymer) composites comprising of high tenacity fibers such as Kevlar, UHMWPE (Ultra High Molecular Weight Poly Ethylene) etc. Although in the past, STFs have been widely characterized by rheometers at low strain rates (≤10 3 s −1 ), but in actual practical scenarios, body armours encounter much higher strain rates (of the order of 10 5 –10 7 s −1 ) under a ballistic impact. The main objective of this study is to capture the dynamics of STFs at such high strain rates by employing Split Hopkinson Pressure Bar (SHPB) technique. The STF sample was synthesized by dispersing 67.5 wt.% of 100 nm silica powder in Poly Propylene Glycol (PPG) and ethanol, using ultrasonic homogenization method. The mechanical response of STF was studied at high strain rates in terms of the stress-strain behavior and variation of the impact toughness with the loading rate of the fluid specimen. It was observed that the impact toughness of STF increased progressively with the specimen loading rate. The peak stress and peak strain rate attained in the SHPB tests were 147 MPa and 22,100 s −1 , respectively. The characteristic transition time of STF was found to be in the range of 13–25 µs. [ABSTRACT FROM AUTHOR]

In the present work, dynamic compression response of polypropylene (PP) based composites reinforced with Kevlar/Basalt fabrics was investigated. Two homogeneous fabrics with Kevlar (K3D) and Basalt (B3D) yarns and one hybrid (H3D) fabric with a combination of Kevlar/Basalt yarns were produced. The architecture of the fabrics was three-dimensional angle-interlock (3D-A). Three different composite laminates were manufactured using vacuum-assisted compression molding technique. The high strain rate compression loading was applied using a Split-Hopkinson Pressure Bar (SHPB) set-up at a strain rate regime of 3633–5235/s. The results indicated that the dynamic compression properties of thermoplastic 3D-A composites are strain rate sensitive. In all the composites, the peak stress, toughness and modulus were increased with strain rate. However, the strain at peak stress of Basalt reinforced composites (B3D, H3D) decreased approximately by 25%, while for K3D specimens it increased approximately by 15%. The K3D composites had a higher strain rate as compared to the B3D and H3D composites. In the case of K3D composite, except strain at peak stress, remaining dynamic properties were lower than the B3D composite, however, hybridization increased these properties. The failure mechanisms of 3D-A composites were characterized through macroscopic and scanning electron microscopy (SEM). [ABSTRACT FROM AUTHOR]

This paper investigates the characterization of in-plane shear properties of thermoplastic composites reinforced with Kevlar/basalt fabrics. Different fabrics had architectures of two dimensional plain woven (2D-P) and three dimensional angle-interlock (3D-A). Intralayer hybridization was performed during the weaving of the fabrics with the combination of Kevlar and basalt yarns. Five 2D-P and three 3D-A composite laminates were manufactured with polypropylene (PP) as a matrix, using compression molding. Iosipescu shear tests were carried out to evaluate the in-plane shear properties. The experimental results revealed that the shear properties including shear modulus, shear strength and shear failure strain of homogeneous composites were improved by 6.5–14.9%, 4.3–19.7%, and 3.2–46.7%, respectively. Similarly, change in the fabric architecture from 2D-P to 3D-A also enhanced the shear strength and shear failure strain by 32.0–41.6% and 7.2–22.5%, respectively. Intralayer hybrid composites had better in-plane shear properties than the interlayer hybrid composites. The fracture morphologies of the specimens were examined by scanning electron microscopy (SEM). [ABSTRACT FROM AUTHOR]

The present study compared the tensile and low velocity impact (LVI) response of Kevlar/basalt fabrics. Homogeneous and hybrid fabrics with structures of two dimensional plain woven (2D-P) and three dimensional angle-interlock (3D-A) were woven with Kevlar and basalt yarns. Interlacing of brittle basalt yarns with high-ductility/high-toughness Kevlar yarns enhanced the tensile strength of 2D-P fabrics by 5.39–50.29% and 3D-A fabrics by 14.80%. Similarly hybridization enhanced the energy absorption of 2D-P fabrics by 8.58–37.71% and 3D-A fabrics by 13.45–20.14%. Change in the architecture from 2D-P to 3D-A also enhanced the tensile and impact resistance of fabrics. Different failure modes induced due to tensile and LVI loads were identified. [ABSTRACT FROM AUTHOR]

Shear thickening is a non-Newtonian flow behavior characterized by the increase in apparent viscosity with the increase in applied shear rate, particularly when the shear rate exceeds a critical value termed as the critical shear rate (CSR). Due to this remarkable property of shear-thickening fluids (STFs), they are extensively used in hip protection pads, protective gear for athletes, and more recently in body armor. The use of STFs in body armor has led to the development of the concept of liquid body armor. In this study, the effect of particle size is explored on the low and high strain rate behavior of nanosilica dispersions, so as to predict the efficacy of STF-aided personal protection systems (PPS), specifically for ballistic applications. The low strain rate study was conducted on cone and plate rheometer, whereas the high strain rate characterization of STF was conducted on in-house fabricated split Hopkinson pressure bar (SHPB) system. Spherical nanosilica particles of three different sizes (100, 300, and 500 nm) as well as fumed silica particles of four different specific surface areas (Aerosil A-90, A-130, A-150, and A-200), respectively, were used in this study. The test samples were prepared by dispersing nanosilica particles in polypropylene glycol (PPG) using ultrasonic homogenization method. The low strain rate studies aided in determining the CSR of the synthesized STF dispersions, whereas the high strain rate studies explored the impact-resisting ability of STFs in terms of the impact toughness and the peak stress attained during the impact loading of STF in SHPB testing. [ABSTRACT FROM AUTHOR]

Kevlar ® fabric reinforced plastics (KFRPs) are specialized composites with multiple layers of fabrics (∼ranging from 20 to 50 layers) designed for high impact applications. In this work, Kevlar-129 fiber was reinforced with polyetherimide (PEI) and polypropylene (PP) to obtain two groups of laminates in three configurations i.e. 16, 24 and 30 layers. Holes of diameter 11.6 mm were profile cut using fiber laser machining system operating at 1070 nm wavelength. Effects of polymeric matrix on the failure of the Kevlar – polyetherimide (K-PEI) and Kevlar – polypropylene (K-PP) laminates were characterized by studying the following: (i) threshold laser power required to make the holes (ii) surface morphology using scanning electron microscopy (iii) damage zone along the laser cut path using scanning acoustic microscopy and optical microscopy. K-PEI laminates underwent material separation at much lesser line energy (ratio of laser power to velocity) than K-PP laminates during laser machining. Scanning electron microscopy (SEM) was used to further analyze the laser cut surfaces. A prominent observation on the laser-irradiated surface was: less recast/resolidified polymer covered the Kevlar fabric in K-PEI as compared to a thicker polymeric layer in K-PP. Heat affected zone and damage factors were evaluated using scanning acoustic microscopy (SAM). Surface roughness and kerf width were also analyzed to understand the effect of laser machining of Kevlar laminates. [ABSTRACT FROM AUTHOR]

The present work reported the mechanical characterization of novel polypropylene (PP) composites reinforced with three-dimensional angle-interlock (3D-A) Kevlar/basalt fabrics. Two homogeneous fabrics with Kevlar (K3D) and basalt yarns (B3D), and a hybrid fabric (H3D) with a combination of both Kevlar and basalt yarns were produced. Three types of two layer 3D-A composites were manufactured using vacuum-assisted compression molding method. Static tensile and in-plane compression tests were carried out on the manufactured composites. The mechanical behavior of the three 3D-A composites was compared in terms of stress-strain response, elastic modulus, strength and failure strain. Influence of hybridization on the mechanical behavior of the 3D-A composites was also studied. Significant improvement in the tensile behavior of 3D-A homogeneous composites was observed due to hybridization. Meanwhile, there was no considerable improvement in in-plane compression behavior. The damage patterns for in-plane compression loading were examined through scanning electron microscopy (SEM) to explore the possible damage patterns such as matrix cracking, fiber failure, delamination and deformation. Numerical simulations were carried out using ABAQUS/Standard, by implementing a user-defined material subroutine (VUMAT) based on the Chang-Chang linear orthotropic damage model. Good agreement between experimental and numerical simulations was achieved in terms of damage patterns. [ABSTRACT FROM AUTHOR]

Experimental and numerical investigations are carried out to determine the low velocity impact (LVI) response of three different polypropylene (PP) composites. Three dimensional (3D) angle-interlock fabrics with Kevlar, basalt and a hybrid combination of both are produced. 3D composites are manufactured with these three fabrics using vacuum-assisted compression molding process with PP resin. LVI tests are conducted using a drop-weight impact equipment at the energy level of 240 J. The LVI response of the three 3D-PP composites is compared in terms of peak force, energy absorption and damage modes. The experimental results indicate that the basalt 3D composites showed 6.62–13.73% higher peak force and H3D composites absorbed 7.67-48.49% more energy than the remaining composites. Results indicate that there is a considerable enhancement in the energy absorbing capability of hybrid composites as compared to Kevlar/PP and basalt/PP composites. Numerical simulations are carried out using the commercial finite element (FE) code ABAQUS/Explicit. A user-defined material subroutine (VUMAT) based on Chang-Chang linear orthotropic damage model, is implemented into the FE code. Good agreement between experimental and numerical simulations is achieved in terms of impact response characteristics. [ABSTRACT FROM AUTHOR]

In this study, low velocity impact (LVI) behaviors of composite laminates reinforced with fabrics of different architecture are investigated. Three kinds of fabric architecture, namely, two-dimensional plain woven (2D-P), three-dimensional orthogonal (3D-O) and three-dimensional angle interlock (3D-A), are prepared with Kevlar 29 (Kevlar) yarns. Composite laminates are manufactured with Kevlar fabrics and polypropylene (PP) resin. These composites are impact tested at 4 m/s and 6 m/s impact velocities. The post-impact response of the composites of different fabric architecture is studied. The results revealed that the impact resistance is mainly dependent on the in-plane stiffness of the laminates. The energy absorption ability is predominantly influenced by the existence of yarns in the thickness direction. The 3D composites absorbed 14–26% higher energy than the 2D laminates. Especially, 3D-A laminates exhibited a higher peak load (14.21–30.25%), more energy absorption (12.7–26.2%) and lower cone formation at the back of the target (25–39%) as compared to 3D-O and 2D-P composites. [ABSTRACT FROM AUTHOR]

In this study, experimental investigations on Kevlar fiber reinforced polypropylene (PP) woven composites under high strain rate compression loading are discussed. Kevlar/PP composite laminates with 8 and 24 layers are fabricated using vacuum assisted compression molding technique. Maleic anhydride grafted-PP (MAg-PP) is added to PP to improve the interfacial property between Kevlar fiber and PP resin. The through-thickness properties at high strain rates from 1370 to 6066 s −1 are obtained using split Hopkinson pressure bar (SHPB) setup. The behavior of PP resin is found to be different than the commonly used thermoset resins, such as epoxy. Dynamic stress–strain relations are drawn to reveal the mechanical properties at high strain rates and these relations appear to be rate sensitive. As a result, the peak stress increased by three times, toughness increased by almost ten times and strain at peak stress increased by as much as two times with an increase in the strain rate. The final failure of the specimens is examined by scanning electron microscopy (SEM) to explore the possible failure mechanisms such as, delamination, fiber failure and shear fracture. [ABSTRACT FROM AUTHOR]

The ballistic impact response of thermoplastic-based composite armors made from Kevlar ® fabric and polypropylene (PP) matrix has been investigated against ballistic test standard NIJ-STD 0106.01 Type IIIA. Kevlar ® fabrics of different architectures, namely 2D plain woven, 3D orthogonal and 3D angle interlock fabrics, were produced and used as reinforcements to fabricate composite armor panels, using compression molding technology. Interfacial property between PP and Kevlar ® was improved by adding a coupling agent called maleic anhydride grafted PP. Reduced density was observed in Kevlar ® thermoplastic-based composites as compared to that of the thermoset-based laminates. Ballistic impact tests were imparted with 9 mm full metal jacket (FMJ) on armor panels having different fabric architecture. Ballistic test results revealed that 2D armor was 2.4–7% more susceptible to damage than 3D armors. Hydrocode simulations were carried out using ANSYS AUTODYN v. 14.0 to obtain an estimate for the ballistic limit velocity and simulate failure modes. Post-impact damage patterns obtained from the simulations were compared with the experimental results to assess the performance of the simulations. Good correlation between the hydrocode simulations and experiments was found, both in terms of failure modes and damage patterns. 3D composite armors were able to confront the 9 mm FMJ projectile; however, the 2D plain woven armors failed. The increase in the ballistic limit from 2D plain woven armor to 3D orthogonal and 3D angle interlock armors was 16.44% and 20%, respectively, indicating the effect of fabric architecture. [ABSTRACT FROM AUTHOR]

• High hardness steel (HHS) sheet with UHMWPE composite backing were tested against a hardened steel core projectile. • The projectile core was eroded by the HHS sheet and stopped in UHMWPE composite. • It is observed that only a core eroded to a certain length and weight by armor system can be defeated. • In numerical modeling core failure strain was determined from the residual weight of cores. • The numerical model can be used to evolve armor design. Thin high hardness steel sheets can be an alternative to expensive ceramic armor systems designed to defeat hardened core projectiles. A thin high hardness steel sheet backed with UHMWPE fiber-reinforced composite was ballistically tested against a 7.62 × 39 mm hardened steel core projectile in a single-stage gas gun. Thin steel sheets of 530 BHN hardness were adhesively bonded with UHMWPE fiber-reinforced composite to fabricate armor plates. Armor plates were able to defeat the projectile showing considerable potential. Tensile strength of steel sheet and UHMWPE-fiber reinforced ply was also determined. A detailed numerical simulation of the impact event was also performed to understand the phenomenon of defeat and penetration in greater detail. The numerical model was calibrated from the recovered projectile's core after the ballistic test. [ABSTRACT FROM AUTHOR]

Statement of the Problem The efficacy of various decontamination protocols to reverse the effect of blood contamination after acid-etching may depend on the type of adhesive. Objectives To compare the effect of blood contamination and various decontamination protocols on acetone-based and ethanol-based total-etch adhesive systems. Methods Occlusal dentin of 64 human molars was etched and contaminated with fresh human blood. The samples were assigned to two groups as per adhesive used: Prime & Bond NT (acetone-based) and Adper Single Bond 2 (ethanol-based) and then subdivided into eight groups: (1) control, (2) no decontamination, (3) water rinsing, (4) re-etching, (5) sodium hypochlorite, (6) sodium hypochlorite/sodium ascorbate, (7) hydrogen peroxide, and (8) ethanol. Adhesives were applied and specimens were prepared for μTBS after composite buildup. The data were subjected to analysis of variance followed by post hoc Tukey test. Results Blood contamination significantly reduced μTBS of both the adhesives. Re-etching and NaOCl/Asc were effective in restoring μTBS to the level of control for both the adhesives whereas NaOCl was effective only for Prime & Bond NT. Conclusion Both re-etching and NaOCl can be used for regaining μ TBS of blood-contaminated acid-etched dentin. NaOCl/Asc yields better results than NaOCl alone, specifically for ethanol-based adhesive. Clinical Significance Knowing the adverse effects of prolonged acid-etching, other alternatives for decontamination of etched dentin after blood contamination should be considered. NaOCl alone or NaOCl followed by sodium ascorbate may prove to be good alternatives. These choices also may determine the type of adhesive system. [ABSTRACT FROM AUTHOR]

• Vacuum compression moulded Basalt-Polyeteherimide (PEI) composites manufacturing. • Optimization of Basalt-PEI composite manufacturing moulding parameters. • Basalt-PEI composite under quasi-static and dynamic high strain rate loading. • Elastic recovery of Basalt-PEI composite can help in reflecting the blast wave. High temperature blast and ballistic resistant light weight fibre reinforced plastic composites are very much in demand. Accordingly, the present investigation is focused on the quasi-static and high strain rate behaviour of Basalt/Polyetherimide (PEI) composite. Nine different types of composite samples were fabricated by compression moulding. The moulding pressures and temperatures were varied in the range of 15–25 bars and 325 °C−375 °C, respectively. Quasi-static testing was done at the rate of 3 mm/min to establish the optimum moulding parameters. High strain rate compression tests in the strain rate range of 900/s−3200/s were performed on the optimum moulded composite specimens. High strain rate testing revealed that 40 layered Basalt/PEI composite moulded at 25 bar pressure and 350 °C attained highest stress of 932 MPa whereas, the same was found to attain 446 MPa under quasi-static loading conditons. Thus, establishing the rate depedency of Basalt/PEI composite. Damage studies revealed that Basalt/PEI undergoes brittle damage, typically resulting in shear plane angle of 42°−45°. SEM micrographs revealed brittle fibre failure and matrix free fibre bundles, indicating the importance of process parameter optimiation. [ABSTRACT FROM AUTHOR]

The present study deals with the quasi-static and high strain rate characterization of Kevlar-129 based thermoplastic composites. Two different thermoplastic matrices, namely, Polypropylene (PP) and Polyetherimide (PEI) were used to manufacture composite laminates. Quasi-static compression tests were performed at strain rates of 0.041 s−1 and 0.045 s−1. High strain rate tests were performed using a split Hopkinson pressure bar apparatus within the strain rates ranging from 2548 s−1 to 4379 s−1. Stress-strain relations reveals the rate-sensitive behaviour of composites. Kevlar/PP (K-PP) showed higher peak stress under quasi-static loading as compared to the high strain rate test. Comparable peak stresses were revealed under quasi-static and high strain rate loading for Kevlar/PEI (K-PEI) composite. Also, high strain rate compression properties such as peak stress, peak strain and toughness of K-PP were 25%, 27% and 6% higher than that of the K-PEI composite. The failure mechanisms of both the composites were characterized through macroscopic and scanning electron microscopy. K-PP failed majorly due to matrix crush and fibre failure while K-PEI failed due to shear cracking. Damage study reveals that a single fibre based composite system can be tailored to act as an energy-absorbing or dissipating material system by varying the thermoplastic matrix materials. • Static and dynamic compressive properties of Kevlar reinforced high-performance polymers. • Kevlar/Polypropylene outperforms over Kevlar/Polyetherimide under both the quasi-static and high strain rate loads. • The quasi-static strength of Kevlar/Polypropylene is 25% higher than its high strain rate strength. • Polypropylene matrix results in ductile failure, while the Polyetherimide matrix results in brittle failure. [ABSTRACT FROM AUTHOR]

Modification of Polylactic acid (PLA), a biopolymer, is a strategy still to be fully explored for the next generation of bioresorbable vascular stent (BVS) biomaterials. With this focus, inclusions upto 5% of Polycaprolactone (PCL) and Magnesium in PLA were tested in the rat subcutaneous model and their cellular and tissue interactions characterized, specifically with respect to inflammatory response, angiogenesis and capsularization. The cytokines IL6, TNF Alpha and IL-1Beta were estimated in the peri-implant tissue, all of which showed a non-significant difference between the non-implanted animals and those containing PLA by 8 weeks, speaking to the benign nature of PLA as an implant biomaterial. Both modified materials, had increased macrophage counts and cytokine levels, except IL6 at 8 weeks. Vascularization only at 8 weeks in PLA PCL containing tissue was significantly higher than pure PLA, which may be more carefully controlled along with the material hydrophobicity for possible efforts towards therapeutic angiogenesis. Capsule thickness, measured by staining with both Hematoxylin & Eosin and Masson's Trichome did not show any differences between materials, including PLA. [ABSTRACT FROM AUTHOR]

Quasi-static tensile test of UHMWPE fiber-reinforced composite laminate is challenging to perform due to low interlaminar shear strength and low coefficient of friction. Tensile tests proposed in the literature were conducted and limitations associated with each method led to the evolution of a new method. Tensile test of single-ply was realized as the best representative of tensile strength of a composite than tensile test of UHMWPE laminate. A fixture was developed for single-ply tests which increased friction and provided the mechanical constraint to slipping. The fixture is easy to fabricate and has provided repeatable results for eight grades of UHMWPE fiber-based (0/90) fabrics. Reported tensile strengths are in quite high range of 900–1500 MPa. • Ballistic composites are quite different from structural composites. • Tensile strength difficult to determine with standard methods. • All available methods tested for efficacy. • A new method is suggested for efficient testing. • Properties of wight commercial grades determined by suggested method. [ABSTRACT FROM AUTHOR]