Synthesis and characterization of spent alumina catalyst and grinding sludge reinforced aluminium-based composite material

In this investigation, an attempt has been made to use the waste material in the fabrication of aluminium-based composite material. Waste spent alumina catalyst (SAC) generated from oil refinery industries has been considered as primary reinforcement particle. Waste grinding sludge (GS) produced from iron forging industry was used as secondary reinforcement material in the preparation of composite. Further, chromium (Cr) has been added to SAC and grinding sludge (GS) reinforced aluminium-based composite material to prevent grain growth as well as to control the grain structure of composite material. Experimental results concluded that by adding 4.5% of GS and SAC with 1.5% Cr in aluminium alloy, mechanical properties such as hardness, compressive strength and tensile strength were significantly improved. Hardness compressive strength and tensile strength was increased by 40.06%, 7.24% and 18.86%, respectively, with respect to the aluminium alloy. However, the reduction in toughness was observed. SEM results depicted uniform distribution of SAC and GS particles in Al/4.5% SAC/4.5% GS/1.5% Cr composite. Thermal expansion behaviour and corrosion weight loss of composite have been also investigated to observe the influence of reinforcement in the aluminium alloy.

Performance Evaluation On Structural Behaviour Of Sisal Fibre Reinforced Concrete

All over the world, construction industries looking forward for the green materials to meet the structural integrity and sustainability in terms of arresting micro cracks in the concrete and also for a secondary reinforcement materials for addition in the concrete. Internal micro cracks in the concrete will reduce the longetivity of the structure and also it results in structural failure. The use of fibres in the concrete is currently used as a secondary reinforcement for strengthening the reinforced concrete members. To make the concrete as a sustainable material and to improve structural integrity in this research Sisal Fibre was used as a secondary reinforcement. Natural fiber such as sisal fibre, appears as an one of the good alternative since they are available in fibrous form and can be extracted from plant leaves at very low cost. In this work, effect of sisal fiber on the strength of concrete for M 25 grade has been studied by varying the percentage of fibers in concrete. Fiber content were varied by 0.05%, 0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35% and 0.40% by volume of concrete. Cubes, Cylinder and Prism were cast to evaluate the Strength Characteristics and to optimize dosage level of fibre in concrete. The reinforced concrete beam was cast by optimum dosage level of fibre to evaluate structural behavior of concrete such as Load deflection, Ductility factor and Stiffness. The result proven, there is significant improvement in structural behavior of Sisal Fibre added Reinforced Concrete when compared to control concrete.

Synthesis and Characterization of Cr, Eggshell and Grinding Sludge Reinforced Aluminum Based Metal Matrix Composites: An Ingenious Experimental Approach

This investigation deals with the utilization of industrial waste to develop aluminum-based composite. Waste eggshell (ES) generated from the food industry has been used as primary reinforcement material. Waste grinding sludge (GS) produced from the iron forging sector was utilized as secondary reinforcement content. Cr content has been further encapsulated to the composite material to prevent the composite material's grain growth. The composite material was developed by the stir casting process. Experimental results concluded that tensile strength, compressive strength, and hardness of base material (AA5052 alloy) had been improved by about 18.02 %, 23.40 %, and 49.53 respectively, by adding 4.5 % of ES, 4.5 % of GS, and 1.5 % of Cr. Microstructural analysis of the AA5052/4.5 % ES/4.5 % GS/1.5 % Cr composite shows the fair distribution of reinforcement content. XRD of the Al/4.5 % ES/4.5 % GS/1.5 % Cr composite shows the occurrence of Al, Fe2O3, CaCO3, CaO, and Cr phases. Corrosion weight loss and thermal expansion behavior of developed composite have also been explored to observe the ES, GS, and Cr addition in the aluminum alloy.

Behavior in mice subjected to a Token Slot-machine: effect of Unpredictable Chronic Mild Stress

Several studies have succeeded in teaching animals (primates, pigeons, rats, but not mice) the value of tokens by having them executing a task using a vending-machine apparatus, where in order to receive the primary reinforcement (food), the animals had to perform a specific action that allowed them to obtain the secondary reinforcement (tokens: metal balls). We tried to assess this kind of behavior in mice that had previously been trained to use some tokens, with the aim of rewarding them not with food, but with other tokens, as a result of a token economy task. We found that mice exhibit economic behavior. Further on, our research tried to investigate the effect of stress on their operant decision-making. Therefore, the mice were divided into two groups: a Control group (n=10) and a group subjected to an Unpredictable Chronic Mild Stress (UCMS) treatment (n=8). We found that chronic stress increases some aspects of sub-optimal economic activity.

Effect of graphite particulate on mechanical characterization of hybrid polymer composites

Quest for producing lightweight and biodegradable materials has encouraged researchers to replace synthetic fibers with natural fibers. Hence a study is made to investigate the effects of introducing secondary reinforcement (natural fibers), stacking sequence, and addition of graphite particles on the mechanical characteristics and water uptakes along with diffusivity of hybrid (glass\jute) composites. Different weight fractions of graphite particulates are incorporated into the epoxy to produce different samples having 4 plies for each sample by hand layup vacuum bagging method. The obtained specimens are subjected to various mechanical tests, water absorption tests as per the ASTM standards, and optical microscopy was used to study the fracture morphology of the samples. The results displayed that the properties are deteriorated a little with the addition of secondary reinforcement, however they have improved with the addition of graphite. E-Glass as skin layer and treated jute as core layer composite exhibits ameliorate tensile strength (201.5 MPa), compression strength (515.12 MPa), flexural strength (106.9 MPa), hardness (25 BHN). However highest impact energy of 26 J is recorded for the sample with jute as skin layer and E-Glass as the core layer. Water absorption tests revealed that the addition of graphite has reduced the water absorption in the hybrid samples.

Effect of rice husk (treated/untreated) and rice husk ash on fracture toughness of epoxy bio-composite

Present work studies the effect of particle reinforcement on fracture toughness of bio-composites. The filler used has been taken as rice husk. Epoxy resin has been taken as matrix material. Composites with varying filler loading of 10, 20, 30 and 40 wt.% were fabricated. The fracture toughness was seen to be increasing with increase in filler loading. However beyond 20% there was a decrease in fracture toughness with increase in filler loading. The effect of fibre treatment on toughness was also observed. Rice husk fibres pre-treated with NaOH were used. It was observed that fracture toughness further improved due to treatment. The increase in fracture toughness was significant. Fracture toughness increased from 1.072 to 2.7465 MPa√mm for 20% reinforcement and after treatment it increased to 2.876 MPa√mm. It was observed that concentration of treatment media also affects the fracture toughness. Further the effect of hybridization was observed by addition of rice husk ash as a secondary reinforcement. The fracture toughness of the resulting composites was remarkably higher than that of pure epoxy.