Development of 3D Angle-Interlock Woven Preforms for Composites

The advent of three dimensional (3D) reinforcements has been mainly to overcome the issue of delamination and improve upon the damage tolerance properties by introducing fibres in the thickness direction for advanced composite applications. 3D preforms can be developed using various techniques. Angle-interlock weaving is one of them. This paper details about the efforts being put at CSIR-NAL for developing angle-interlock woven preforms. Four types of angle-interlock structures viz., layer-to-layer and through thickness (both with and without stuffer yarns) were developed using 6K, 400 Tex TC-33 grade Carbon tows on a custom designed handloom. The preforms without stuffer yarns had 4 layers of warp and were of 1.5± 0.2 mm thick. Preforms with stuffer yarns had 6 layers of warp (including 2 stuffer yarn layers) and were of 2.3±0.1 mm thick. Thermoset composites were prepared from these preforms using EPOLAM 2063 (an epoxy based resin system) by RTM process. The fibre weight fraction for these composites ranged from 0.53 to 0.58 and they were subjected to mechanical tests such as tensile, flexural and interlaminar shear strength. Test results showed improved response (in the warp direction) with respect to shear properties while the tensile and flexural properties were equivalent to that of the plain woven composites

Novel Design of Cocured Composite ‘T’ Joints with Integrally Woven 3D Inserts

Composites can be exploited to their full potential when cocured, wherein different parts are made and bonded together in a single cure operation to realise an integral structure. The key element in a typical cocured construction is T-joint, which forms the primary load transfer mechanism between the skin and stiffener in a structural assembly. T-joints are particularly vulnerable for pull off loads and researchers are looking at various techniques to improve the pull strength viz. stitching, tufting, 3D weaving, multilayer weaving, 3D braiding and the like. The present work uses a novel technique to improve the strength of T-joints by employing a hybrid design wherein an integral 3D ‘T’ insert is interleaved with a conventional T-joint. Inserts were woven using 3K and 6K carbon tows and incorporated in T-joints using CSIR-NAL proprietary process called ‘Vacuum Enhanced Resin Infusion Technology (VERITy)’ process. Several configurations of T-joints were tested in an UTM in the pull mode till the failure to assess the efficacy of integrally woven 3D inserts. It was observed that the initial failure load was nearly the same across the various T-joint configurations tested whereas the maximum failure loads were quite different. The normalised strength of T-joints with integrally woven 3D inserts in pull off mode was enhanced by about 30% when compared T-joints without the insert and thus vindicating the usage of integrally woven 3D insert in a cocured T-joint. The insert is conceived in such a way that it can be easily incorporated in the design of cocured structures

Determination of ‘Pressure Application Window’ (PAW) for the Vacuum Enhanced Resin Infusion Technology (VERITy) Process

Vacuum Enhanced Resin Infusion Technology (VERITY) is a hybridization of the Vacuum Assisted Resin Transfer Moulding (VARTM) and the autoclave molding processes. In this technique, innovative tooling concepts have been adopted and more importantly, an external pressure is applied at an appropriate time, after infusion has been completed. The application of external pressure ensures uniform consolidation, optimum fiber content, and low void content in the laminates. In the present study, a systematic approach has been taken to determine the pressure application window (PAW) for the RTM 120 resin system. Viscosity measurements, dielectric measurements and squeeze flow experiments were employed to determine the PAW. Parameters of void content and interlaminar shear strength (ILSS) have been chosen to evaluate the PAW determined

Flight Data Analyses of Fiber Optic Based Airworthy Structural Health Monitoring System for UAV using Artificial Neural Networks

This paper presents an airworthy, Fiber Bragg Gratings (FBG) based, Structural Health monitoring System (SHM) system for an Unmanned Aerial Vehicles (UAV). Various design issues pertaining to sensors location, embedment, integration of interrogation system instrumentation, online data recording, implementation of mathematical models for load estimations and GUI based flight data processing software are addressed. FBG data were processed to identify both vibration modes and loads using signal processing techniques and artificial neural network (ANN) algorithms respectively. The issue of sensor malfunctioning is also addressed wherein sensor failure was incorporated in the in-flight data during post processing for various flight regimes. The ANN based methodology was designed for identification of sensor failure and prediction of the estimated strain based on the available values from working (non-failed) sensors. The performance of load estimation was also compared in both the scenario (i.e. in the event of sensor failure and without sensor failure)

Flight Data Analyses of Fiber Optic Based Airworthy Structural Health Monitoring System for UAV using Artificial Neural Networks

This paper presents an airworthy, Fiber Bragg Gratings (FBG) based, Structural Health monitoring System (SHM) system for an Unmanned Aerial Vehicles (UAV). Various design issues pertaining to sensors location, embedment, integration of interrogation system instrumentation, online data recording, implementation of mathematical models for load estimations and GUI based flight data processing software are addressed. FBG data were processed to identify both vibration modes and loads using signal processing techniques and artificial neural network (ANN) algorithms respectively. The issue of sensor malfunctioning is also addressed wherein sensor failure was incorporated in the in-flight data during post processing for various flight regimes. The ANN based methodology was designed for identification of sensor failure and prediction of the estimated strain based on the available values from working (non-failed) sensors. The performance of load estimation was also compared in both the scenario (i.e. in the event of sensor failure and without sensor failure)

Abstracts of National Conference on Research and Developments in Material Processing, Modelling and Characterization 2020

This book presents the abstracts of the papers presented to the Online National Conference on Research and Developments in Material Processing, Modelling and Characterization 2020 (RDMPMC-2020) held on 26th and 27th August 2020 organized by the Department of Metallurgical and Materials Science in Association with the Department of Production and Industrial Engineering, National Institute of Technology Jamshedpur, Jharkhand, India. Conference Title: National Conference on Research and Developments in Material Processing, Modelling and Characterization 2020Conference Acronym: RDMPMC-2020Conference Date: 26–27 August 2020Conference Location: Online (Virtual Mode)Conference Organizer: Department of Metallurgical and Materials Engineering, National Institute of Technology JamshedpurCo-organizer: Department of Production and Industrial Engineering, National Institute of Technology Jamshedpur, Jharkhand, IndiaConference Sponsor: TEQIP-

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Not AvailableThe increasing demand for crop production, given worldwide increases in the human population, puts pressure on moving natural resources towards sus-tainable development. This creates a big challenge for the upcoming generation. If improvement is not successful, there exists the unfortunate consequence that global food production may soon become insufficient to feed all of the world’s people. It is therefore essential that agricultural productivity be significantly increased in a more sustainable and environmentally friendly approach. Plant-beneficiary rhizo-bacteria (PBR) naturally activate microorganisms found in the soil. Because they are inexpensive, effective, and environmentally friendly, PBR are gaining impor-tance for use in crop production by restoring the soil’s natural fertility and protect-ing it against drought and soil diseases, thereby stimulating plant growth. PBR decrease the use of chemical fertilisers, pesticides, and artificial growth regulators; the intensive use of these inputs has led to severe health and environmental hazards, such as soil erosion, water contamination, pesticide poisoning, decreased ground-water table, water logging, surface crusting and depletion of biodiversity. The use of PBR has been proven to be an environmentally sound way of increasing crop yields by facilitating plant growth through either a direct or indirect mechanism with the aim of sustaining soil health over the long term. (7) (PDF) Towards Plant-Beneficiary Rhizobacteria and Agricultural Sustainability. Available from: https://www.researchgate.net/publication/325854138_Towards_Plant-Beneficiary_Rhizobacteria_and_Agricultural_Sustainability [accessed Nov 19 2018].Not Availabl