Effect of Alternate Metals for use in Natural Fibre Reinforced Fibre Metal Laminates under Bending, Impact and Axial Loadings

AbstractFibre Metal Laminate (FML) is largely used in the manufacture of aircrafts. The commercially available FMLs, GLARE, CARALL (CArbon Reinforced ALuminium Laminate) and ARALL make use of Aluminium metal. Other FMLs that are under study by researchers make use of metals such as Titanium and Magnesium based alloys. Owing to the high cost of carbon fibre and the necessity for environment friendly alternatives, in the present work, a portion of carbon is replaced by natural fibre jute in CARALL and CARMAL (CArbon Reinforced MAgnesium Laminate). To the knowledge of the authors, this attempt has not been made before in the field of FMLs. The resulting CArbon-Jute Reinforced ALuminium Laminate and CArbon-Jute Reinforced MAgnesium Laminate are named as CAJRALL and CAJRMAL. Both these laminates are made by hand layup technique and then compressed in a compression moulding machine. The CAJRALL and the CAJRMAL specimens are subjected to Axial, Flexure and Impact tests according to ASTM standards. The effect of the orientations of fibres and influence of the stacking sequences of the fibre and metal combinations and the use of alternating metals on the mechanical performance, are experimentally investigated. The experimental and theoretical results as well as the results obtained through Finite Element Analysis are found to be in close agreement. Also the failure of the FML is predicted by conducting micro level structure analysis

Experimental Investigation on the Impact of Presence of Natural Fibre on the Mechanical Performance of a Light Weight Hybrid Bonded Laminate

Abstract—Natural fibres play a vital role in the area of composites and have found wide acceptance in this area. In this work, two kinds of hybrid laminates are studied, one with carbon, jute and aluminium termed as CAJRAL and the other, CARAL, with carbon and aluminium only. The purpose of this study is to analyse the effect of addition of natural fibre jute in the fibre metal laminate on its mechanical behavior. Experimental studies are undertaken on tensile, flexure and impact properties of both CARAL and CAJRAL. It is observed that, CAJRAL’s mechanical performance deviates from that of CARAL by only a maximum of 24%, with respect to axial and impact loadings. As far as the bending behaviour is concerned, CAJRAL performs even better than CARAL, due to the presence of jute fibre. Moreover the experimental findings are compared with analytical simulation and are found to be in close agreement. Keyword-CARAL, CAJRAL, Tensile, Bending, Impact I

Effects of Different Operating Temperatures on the Tensile Properties of the Grid Plate Hardfaced with Colmonoy in a Pool Type Sodium Fast Reactor

In sodium-cooled fast reactors (SFRs), the grid plate is a critical component which is made of 316 L(N) SS. It is supported on a core support structure which is also made of 316 L(N) SS. This assembly is immersed in a pool of sodium which acts as a coolant. If there is a direct contact between the grid plate and the flange of core support structure, self-welding takes place between them at the high operating temperature of SFR by a thin sheet of liquid sodium which gets into the gap between them as this sodium acts as a metallic gum. To avoid self-welding, the bottom plate of the grid plate is hardfaced with Colmonoy 5 by PTAW so that the direct contact between those two components is avoided. Due to the difference in coefficients of thermal expansion between the base metal and the coating, the interface is subjected to tensile force which may weaken the bonding strength between them at higher temperatures. Therefore, the weldment should be able to withstand the tensile force at higher operating temperatures for which hot tensile properties of the base metal and the weldment have been determined to study the compatibility between them after hardfacing for the reliable operation of SFR

Effect of delamination on buckling strength of unidirectional glass-carbon hybrid laminates

23-29An experimental study is designed to understand the effect of delamination on critical buckling load and mode of failure for glass/carbon hybrid laminates. Firstly, delaminated specimens are compressed using a universal testing machine and buckling tests performed after the ends of each specimen are hinged to a special fixture designed to permit rotational boundary conditions. Non-linear buckling analysis based on incremental iteration method is conducted using finite element analysis (FEA) package (ANSYS) after conducting tensile tests to find the material properties. Critical buckling loads are found for symmetric [C0/G45/G-45/G90]s and anti-symmetric [C0/G45/G-45/G90//G90/G45/G-45/C0] laminate configurations with four different delamination lengths (a/L= 0.2, 0.3, 0.4 and 0.5) created at two different delamination positions (t/h = 0.5 and 0.25). In this study, the critical buckling load decreased as the delamination length increased. Moreover, the critical buckling load tended to decrease when the delamination approached the surface. </span

Towards Unified Online-Coupled Aerosol Parameterization for the Brazilian Global Atmospheric Model (BAM): Aerosol–Cloud Microphysical–Radiation Interactions

In this work, we report the ongoing implementation of online-coupled aerosol–cloud microphysical–radiation interactions in the Brazilian global atmospheric model (BAM) and evaluate the initial results, using remote-sensing data for JFM 2014 and JAS 2019. Rather than developing a new aerosol model, which incurs significant overheads in terms of fundamental research and workforce, a simplified aerosol module from a preexisting global aerosol–chemistry–climate model is adopted. The aerosol module is based on a modal representation and comprises a suite of aerosol microphysical processes. Mass and number mixing ratios, along with dry and wet radii, are predicted for black carbon, particulate organic matter, secondary organic aerosols, sulfate, dust, and sea salt aerosols. The module is extended further to include physically based parameterization for aerosol activation, vertical mixing, ice nucleation, and radiative optical properties computations. The simulated spatial patterns of surface mass and number concentrations are similar to those of other studies. The global means of simulated shortwave and longwave cloud radiative forcing are comparable with observations with normalized mean biases ≤11% and ≤30%, respectively. Large positive bias in BAM control simulation is enhanced with the inclusion of aerosols, resulting in strong overprediction of cloud optical properties. Simulated aerosol optical depths over biomass burning regions are moderately comparable. A case study simulating an intense biomass burning episode in the Amazon is able to reproduce the transport of smoke plumes towards the southeast, thus showing a potential for improved forecasts subject to using near-real-time remote-sensing fire products and a fire emission model. Here, we rely completely on remote-sensing data for the present evaluation and restrain from comparing our results with previous results until a complete representation of the aerosol lifecycle is implemented. A further step is to incorporate dry deposition, in-cloud and below-cloud scavenging, sedimentation, the sulfur cycle, and the treatment of fires