Nano Alumina Research Articles

The Effect of Quenching in Different Concentrations of Alumina Nano Fluids on Overall Properties of Al-6061

The Effect of Quenching in Different Concentrations of Alumina Nano Fluids on Overall Properties of Al-6061

Synthesized Nanoaluminum Oxide with Al2024 to Investigate Wear Behavior by Grey Relational Approach and ANN

Aluminum metal matrix composites (AMCs) have been employed in automobile manufacturing to reduce weight. Also this research concentrates on the tribological performances on the processed AMCs by the stir casting liquefying method. The aluminum alloy Al2024 was employed to nanoparticles of aluminum oxide for the preparation of AMCs with constant processing condition of stirring speed to produce the homogeneous dispersion. The processed composites were further investigated to identify the wear characteristics. Therefore, the dry sliding condition was achieved on the processed composites. The input parameters of dry sliding conditions are sliding distance, functional load, and sliding velocity, and the output characteristics are wear rate and coefficient of friction (COF). Those input parameters are framed by the Taguchi L9 array and parameters were further employed to optimize with grey relational analysis. From the L9 parameters, the better wear rate and COF were accumulated in the following parameter: 2,100 mm of sliding distance, 25 N of functional load, and 2.5 m/s of sliding velocity, respectively. Then the wear rates and COF values are subjected to produce the predicted responses with supporting of artificial neural network. Most of the predicted values are much higher than the actual wear response vales. The wear resistance of all the samples composed better performances with dispersion of nanoaluminum oxide particles on the Al2024 alloy.

Effect of nanoparticle on mechanical properties of activated tungsten gas welding of austenite stainless steel 316L and optimization of process parameters

Abstract Austenite stainless steel 316L was developed to improve corrosion resistance and is widely used in automobile components, thermal power plants, and pressure vessels due to their superior toughness and intergranular corrosion resistance. The austenite stainless steel 316L has a low carbon content of 0.03%, which helps in minimizing harmful carbide precipitation during welding. The joint strength of welded joints is poor unless proper care is taken. As a result, an attempt was made to use an activated Tungsten Inert Gas (A-TIG) welding procedure to improve the joint strength of butt welded joints of austenitic stainless steel 316L. The process parameters such as current, the volume of flow, and filler diameter were chosen in the study and generated an L 9 design matrix using MINI Tab software. The welded joints were prepared as per the design matrix using the activated flux of aluminum oxide nano powder as per the combination of process parameters. The mechanical tests such as tensile strength, hardness, and impact strength were evaluated and microstructural evaluation of welded joints was also assessed. The input parameters were optimized for better tensile strength of joints using Taguchi S/N analysis. It is found from the optimization that the highest ultimate tensile strength of 690.40 MPa was obtained at a current of 90 A, shielding gas flow of 13 l min–1, and filler material diameter of 2.5 mm. The model was also validated by conducting experiments.

An evaluation on mechanical properties of vaccum bagging processed kenaf epoxy nano aluminium oxide and nanographene composites

This paper aims to study the mechanical properties of hybrid polymer composites and the addition of primary and secondary fillers the nano-aluminum oxide and nanographene to the Kenaf epoxy composites. The vacuum bagging method was used to fabricate the composites. The advantage of using vacuum bagging is to reduce blowholes. The weight ratio of Kenaf fiber 50%–60%, matrix 40%, fillers nano-aluminum oxide 0%–6%, and nanographene 0%–3% was considered. Mechanical properties like Tensile strength, Young’s modulus and elongation, flexural strength, flexural modulus, hardness, impact strength, and compression strength were tested.6% nano aluminum oxide and 3% nanographene show a 125% increase in tensile strength, a 45% increase in flexural strength, and almost four times higher flexural modulus recorded. 42% increase in compression strength, and an increase of 40% in impact strength. The highest Vickers hardness is 27. An increase in primary and secondary fillers decreases and a combination of increases the mechanical properties.

Effect of nano aluminum nitride filler on mechanical, thermal, and dielectric properties of the glass/mullite composites for low‐temperature co‐fired ceramic applications

AbstractMullite/glass/nano aluminum nitride (AlN) filler (1–10 wt% AlN) composites were successfully fabricated for the low‐temperature co‐fired ceramics applications that require densification temperatures lower than 950°C, high thermal conductivity to dissipate heat and thermal expansion coefficient matched to Si for reliability, and low dielectric constant for high signal transmission speed. Densification temperatures were ≤825°C for all composites due to the viscous sintering of the glass matrix. X‐ray diffraction proved that AlN neither chemically reacted with other phases nor decomposed with temperature. The number of closed pores increased with the AlN content, which limited the property improvement expected. A dense mullite/glass/AlN (10 wt%) composite had a thermal expansion coefficient of 4.44 ppm/°C between 25 and 300°C, thermal conductivity of 1.76 W/m.K at 25°C, dielectric constant (loss) of 6.42 (0.0017) at 5 MHz, flexural strength of 88 MPa and elastic modulus of 82 GPa, that are comparable to the commercial low temperature co‐fired ceramics products.

Experimental investigation on fabrication and characterisation of Mg-Al2O3 surface composites

ABSTRACT The current study attempted to introduce nano-aluminium oxide (Al2O3) particles into ZE41 alloy via friction stir processing (FSP). The effect of these nano-Al2O3 particles on the mechanical and tribological characteristics of ZE41 alloy is investigated. The results of microstructural studies revealed the uniform distribution of Al2O3 particles and substantial grain refinement in the stir zone by FSP. Enhanced microhardness was observed in the processed region due to the grain refinement and the occurrence of regularly distributed Al2O3 particles. The wear resistance was also seen increased with the incorporation of the Al2O3 particles. Moreover, the effect of FSP parameters on the successful incorporation of nano-Al2O3 particles in ZE41 alloy without any defect is also realised.

Effect of nano-alumina and graphene oxide on the behavior of geopolymer composites: A state of the art of review

Geopolymer composite has been widely recognized as an environment-friendly alternative to cement composite. Despite its popularity, Geopolymer (GP) has a limited number of real-world applications due to various factors affecting its performance. As a result, various novel techniques are adopted to enhance the performance of geopolymers; one such promising method is the use of nanomaterials. In order to improve material performance, nanomaterials focus on altering the properties of materials at the nanoscale. Nanomaterials influence the characteristics of GPs in their hardened and fresh state by microstructure modifications. The present review study concentrates on the impact of graphene oxide (GO) and nano-alumina (NA) on the behavioral assessment of GP composites, where the microstructural alterations brought on by their use are carefully assessed. Further, the influence of microstructural modifications on the hardened properties, such as mechanical and durability characteristics, as well as the fresh properties, such as workability and setting time, is explored. The review of research studies so far has revealed that GPs included with NA and GO have the potential to enhance the hardened state properties while adversely affecting the properties of the fresh state. Further, NA and GO’s distinct properties enable their use in high-temperature resistant composites, as coatings, and in a variety of uses associated with the environment, including wastewater treatment. However, the cost and energy associated with producing nanomaterials and their detrimental effect on human health and the ecosystem while they are in use prevent their widespread application, necessitating the need for research that balances all aspects.

The effects of nano-alumina particles on the enrichment of tensile, flexural and impact properties of carbon fiber-reinforced epoxy composites

An experimental investigation to determine how the mechanical properties of carbon fiber-reinforced epoxy-based composites with alumina nanoparticles are affected by the fiber and filler materials. The analysis used a digital Universal Testing Machine (UTM) and an impact tester. The weight percentage of nano alumina particles are 1, 2, 3, 4, and 5. Besides, the carbon fiber contents are varied as 34, 33, 32, 31, and 30 wt%, respectively. The hand layup technique fabricated the hybrid composite. The epoxy resin matrix was kept constant (65%). All the test specimens analyze through ASTM standards. The tensile strength, flexural strength, impact strength, and water absorption percentages of all fabricated hybrid composites observed between 59.51 and 78.45 MPa, 38.68–50.99 MPa, 12.12–16.81 kJ/m2 and 1.92–2.17% respectively. The manufactured composite specimens' mechanical properties increase with the weight percentage of the filler particles. An additional quantity of filler (3, 4, and 5 wt%) substances in the epoxy matrix caused a reduction of mechanical properties. Experiment results show that increasing the amount of nano alumina particles in composites leads to notable improvements in the fabricated composites' tensile, flexural, impact, and water absorption capability. These mechanical property enhancements increase from the epoxy resin matrix to the carbon fiber and alumina nanoparticles. The outcome of strong bonding connections between the fiber and matrix demonstrates the developed resistance to thread draw out about fiber-reinforced composites lacking nano alumina particles.

Investigation of the combustion processes of gas-generating flame extinguisher cartridges with car-bon combustible

The aim of the work is to search optimal compositions of gas-generating flame extinguisher cartridges, which should catch fire in very short periods of time, measured within 10-15 milliseconds, in this regard, studies of the flash point with a minute delay in ignition of pyrotechnic components were conducted. The flash point of the initial components, including nano aluminum T = 4200 C, has been established. The optimal composition of the flame extinguisher is NA – 80; Nano Al – 5; Nano C – 15, with this composition the flash point decreases to T = 3500 C. It should also be noted the minimum sensitivity of this composition, which is 0.02 MPa. In the case of increasing carbon content up to 20%, burning as well as its speed, decrease to the extent that it leads to the decay of combustion through radiation heat loss.

Improving the chloride binding capacity of alkali activated slag by calcium and aluminum enriched minerals

In this paper, a modified alkali activated slag with improved chloride binding capacity is proposed by introducing calcium and aluminum enriched phases in the binding system. The Ca and Al phases are added in order to promote the formation of AFm type phases in alkali activated system and then transformed into Friedel's salt (Fs) when in contact with chloride. The effects of calcium and alumina type on phase composition, chloride binding behavior, mechanical property of modified alkali activated slag binders are discussed. The results show that the addition of Ca and Al enriched minerals effectively improve the chloride binding capacity of the binder up to 44.4%. The combination of calcium hydroxide and metakaolin shows the highest binding efficiency, followed by calcium nitrite and cement. Metakaolin exhibits better modification on chloride binding capacity than nano alumina. The incorporation of Ca and Al enriched minerals together successfully promotes the formation of AFm type phases (Mc and AFm-NO2) in alkali activated system, while the addition of metakaolin increases the reaction degree and the mean chain length of C-(A)-S-H gels, contributing to the chloride binding capacity. The mechanical properties of alkali activated slag are also improved by adding calcium hydroxide, cement, and alumina enriched minerals, while calcium nitrite exhibits a slight negative effect.

Using microfluidic technology to prepare octogen high-energy microspheres containing copper–aluminum composite particles with enhanced combustion performance

Aluminized explosives are widely used in military applications. However, the easy agglomeration of aluminum (Al) powder and its high ignition temperature greatly hinder the reaction of nano aluminum (n-Al) in the process of explosion, thus affecting the combustion and explosion of aluminum-containing explosives. In the present study, copper (Cu) coated n-Al composite particles were introduced into aluminized explosives, and Cu coated n-Al composite particles and ball-milled octogen (HMX) energetic microspheres were prepared via droplet microfluidic technology using binder. The morphology, crystal form, thermal properties, combustion, and mechanical sensitivity of the microspheres were studied using a variety of techniques. The prepared microspheres had regular spherical morphology and uniform particle size, with an even distribution of particles. Using microfluidic technology will not destroy the crystal form of each particle. The introduction of Cu promoted the thermal decomposition of HMX. The mechanical sensitivity of the prepared Cu/Al microspheres was lower than that of the microspheres only containing n-Al. The Cu/Al microsphere samples exhibited excellent and stable combustion performance, and that the addition of Cu increased the combustion speed compared to the microspheres only containing n-Al. This technology represents an inexpensive and simple way to improve on existing aluminized explosives.

Synthesis, Analysis, and Characterization of Aluminum Nanoparticles Coated with 2,2,4-Trimethylpentane

In this study, to solve the problem of low activity of aluminum nanoparticles in combustion, aluminum nanoparticles were coated with 2,2,4-trimethylpentane (C8H18-Al), enabling the deactivation of aluminum nanoparticles to be effectively inhibited. The morphological characteristics, particle size distribution, chemical state, and thermal properties of C8H18-Al were characterized via SEM, TEM, DLS, XPS, and TG-DSC. The stability and energy performance of C8H18-Al were studied based on the national standard test method. The results showed that C8H18-Al had a typical shell–core structure with a smooth surface and good sphericity. The particle size was normally distributed, and the content of active aluminum nanoparticles was high (85.45%), with good thermal stability and a fast energy release rate (about four times that of ordinary nano aluminum particles). The results demonstrated that an in situ C8H18 coating is beneficial for the preparation of structurally stable aluminum nanoparticle composites with good performance.

The Performance of Alkali-Activated Self-Compacting Concrete with and without Nano-Alumina

The environmental pollution crisis has infiltrated all aspects of life, making it hard to avoid the hazards. To address this, it is essential to recycle industrial waste through green concrete technology, such as ground-granulated blast furnace slag (S), silica fume, and fly ash (FA). In this study, the effect of nano-alumina (NA) on the fresh and hardened stag of fly ash and/or slag-based alkali-activated self-compacting concrete (A-ASCC) cured in an ambient environment was investigated. Three different types of binders were used: 100% slag, 50% slag and 50% fly ash, and 100% fly ash. Four ratios of nano-alumina (0%, 0.5%, 1%, and 1.5%) were used as partial replacements for binder materials. The fresh characteristics of A-ASCC were evaluated by indicating the slump flow, T50 value, V-funnel, and L-Box tests. The mechanical properties of A-ASCC were evaluated by measuring the compressive strength, flexural tensile strength, and splitting tensile strength test values to assess the qualities of the hardened state. Scanning electron microscopy (SEM) was also used to clarify the microstructure of the A-ASCC specimens. Regardless of the binder materials used, the addition of NA has a negative effect on fresh state performance. The mechanical performance of alkali-activated A-ASCC was significantly improved by the incorporation of NA. The incorporation of NA with 50% slag and 50% fly ash showed better properties than other binder materials. However, the highest flexural and compressive strengths were achieved with 1% NA and 100% FA, and the maximum splitting tensile strength was achieved with 1.5% NA. Furthermore, using NA significantly increases the A-ASCC setting time and may be used to produce A-ASCC in an ambient environment.

Statistical Analysis of Mechanical Strength and Dielectric Breakdown of Polyester Nano-Alumina Composites

The mechanical and electrical properties relation are very important, especially for brittle material. Nano Alumina-unsaturated polyester (PS/Al2O3) composites were prepared by casting PS with different percentages (1, 2, 3, and 4 wt%) of Nano alumina. Electrical breakdowns caused cracks to form around the breakdown point, and the length and quantity of cracks increased with dispersed powder added increases. The research involved determining Weibull modulus from an electrical strength test, and mechanical strength by piston-on-three-ball test. The results showed that Weibull modulus and dielectric breakdown increase during the rate of rising voltage (RRV) increases, especially 5 kV/s. the maximum Weibull modulus measured by the electrical breakdown was at a high RRV is 34.58 (PS/Al2O3). High RRV leads to electromechanical breakdown and electrothermal strength at low RRV. While the Weibull modulus by the piston-on-three-balls test is lower than the Weibull modulus calculated by electrical strength. Therefore, this mechanical test is more accurate in identifying defects that fail due to an increase in the affected area of the applied stress. Scanning electron microscope (SEM) images showing the homogeneous distribution of the powders within the polymeric matrix. Some pores were present in the structure of the composite despite the measures taken to increase the dispersion using ultrasound waves. Those pores caused fluctuating results in all electrical and mechanical tests.

Propiedades del concreto de nano-alúmina con arena de circón como finos bajo variadas temperaturas elevadas

Los materiales de construcción de hormigón ahora se juzgan no solo por sus características económicas sino también por su capacidad de servicio. Los avances en la producción de hormigón ahora también se centran en mejorar el comportamiento resistente al fuego del hormigón. La sustitución de los áridos finos es mucho más deseable cuando estos poseen adecuadas características de resistencia al fuego. El presente trabajo de investigación comprende la urgente necesidad de prestar atención al comportamiento resistente al fuego del concreto minimizando al mismo tiempo el uso del agregado Natural River. Además del reemplazo de agregados finos, la nanoalúmina se usa como aditivo de cemento para respaldar de manera beneficiosa la durabilidad del concreto a través de sus características nanométricas. La arena de circón se usa hasta en un 50 % del agregado de arena de río natural y la nanoalúmina se usa en un 2 % en peso del aglomerante de cemento. Este trabajo de investigación se enfoca en la utilización de arena de zircón como agregado fino para producir concreto.

Study on the high and low temperature performance of nano alumina modified asphalt mixture

To improve the high and low temperature performance of asphalt mixture, nano alumina was used as additive in this study. Firstly, the high temperature characteristics of asphalt mixture with different content of nano alumina were studied by rutting test and dynamic creep test. Secondly, the fatigue properties of modified asphalt mixture at different temperature were tested by indirect tensile fatigue test. Finally, the low temperature bending test and indirect tensile test were used to evaluate the low temperature performance. The results show that nano alumina can improve the high temperature and fatigue properties of asphalt mixture to some extent, while the low temperature performance decreases slightly.

EXPERIMENTAL STUDY ON PROPERTIES AND MICROSTRUCTURE OF NANO MODIFIED ULTRAFINE CEMENT-BASED GROUTING MATERIAL

The traditional cement-based grouting materials commonly used for repairing cracks in highway tunnels have large particle sizes and are easy to block pipes. As such, ultrafine cement-based grouting materials were modified by adding nano-silica (NS), nano-alumina (NA), and carbon nanotubes (CNTs) to improve their grouting, stability, and strength. The results showed that after adding different nano-materials, the fluidity and setting time of the grouting slurry decreased to different degrees, and the maximum values decreased by 41.38% and 42.9%, respectively. Among them, CNTs had the most significant effect, followed by NS. At the same time, the water bleeding rate of the grouting slurry decreased. When 2% NS and 0.5% CNTs were added, water bleeding would not appear. The compressive strength of nano modified grouting materials at all stages would increase first and then decrease with the increase of dosage. The dosages of NS, NA, and CNTs were 1.0%, 1.0%, and 0.1%, respectively, and the compressive strength increased by 24.6%, 4.2%, and 9.2% in 28 days, respectively. X-ray diffraction and scanning electron microscopy tests showed that the surface effect of NS and CNTs can improve the hydration reaction efficiency and hydration products; bridging and nucleation can reduce the crack spacing and structural pores between different particles, and improve the connection between hydration products. The amorphous materials produced by NA can fill the pore structure, while the cementation performance of amorphous materials was poor and had limited contribution to the strength.

Experimental investigation on soil stabilization technique by adding nano-aluminium oxide additive in clay soil

In this research article, soil stabilisation is carried out by the latest method: nanotechnology. The stabilizer nano-aluminum oxide is used as a stabilising agent in concentrations of 0.2%, 0.4%, 0.6%, 0.8%, 1%, and 1.2%. Because it is 99% pure and nanoscale, it has a large surface area for analysing the properties and strength of soil tests such as Atterberg's limit, pycnometer, proctor compaction test, California bearing ratio test, and unconfined compressive strength. These tests are done for parent soil and soil with different percentages of nanomaterials. The nanostabilizer addition increases the unconfined compressive strength, California bearing ratio, liquid limit, and optimum moisture content value. One percentage of nano-aluminium oxide is considered an optimum dosage. Beyond the optimum amount, there is a change in soil property. The CBR value, liquid limit, and OMC of soil all go down, so it is recommended to use 1% nano-aluminum oxide to improve sub-grade clay soil.

Evaluation survey of concrete composite using nano and micro silica materials for better properties

Abstract Concrete will be the very flexible material. Because of continuous and persistent demands made on concrete to assemble the several problematic necessities, extensive examination work is being carried out in region of concrete method. The engineers have frequently pushing restrictions to expand its presentation with support of supplementary cementitious materials and innovative chemical admixtures such as steel slag, fly ash, and silica fume and so on. Nanomaterial concrete is advanced one the composition of nanomaterial concrete it has following water, coarse aggregate, cement nano silica grain of the size of 10 nm-140 nm and fine aggregate. The nano materials like nano alumina, nano titanium oxide, nano silica, and carbon nano tubes, so on, which are currently utilized in concrete to change its strength assets. The “nano materials” have functions or properties diverse from same materials of bigger size. The “nano materials” have a bigger value of ratio among volume and surface region than other same particles in larger size, creating the “nano-materials” much reactive. The “nano silica” will react with C3S and C2S in cement &generate CSH-2 that will create a solid &strong connection of gel. In current survey, properties of strength like split tensile, compressive, and flexural strength of M50 and M40 grades of concrete with utilization of nano silica (1%, 1.5%, 2%, 2.5%) and micro silica (5%, 7.5%, 10%, 15%) as incomplete replacement of cement were deliberated. It was establish from evaluation survey that concrete composites with better properties could be generated utilizing nano silica, micro silica, and mixture of nanosilica and micro silica.

Investigation on the Surface Condition of Gamma Irradiated Silicone Rubber Micro-Nanocomposites

Silicone rubber (SR) micro nanocomposites formed with micro-ATH and nano-alumina particles have been subjected to different levels of gamma-ray irradiation to understand the characteristic variation in the surface condition of the material through contact angle measurement, Atomic Force Microscopy (AFM) studies, water droplet-initiated corona inception voltage (CIV) measurement and by laser-induced breakdown spectroscopy (LIBS) analysis. It is realized that the recovery rate of silicone rubber micro nanocomposites is less compared with the base SR material. It is observed that, irrespective of the level of irradiation, the contact angle and water droplet initiated CIV of the specimen have shown direct correlation. FTIR analysis clearly indicates variation in methyl group formation on irradiation is less with S2 specimen. It is also observed that fractal dimension calculated by three different techniques for the surface profile data obtained using AFM is in directly in proportion with average surface roughness. In addition, the lacunarity values of the irradiated samples followed the same pattern as that of the average surface roughness. The variation in thermal degradation temperature has been analyzed by adopting thermogravimetric analysis (TGA). The calculated plasma temperature values from laser-induced breakdown spectroscopy and the crater depth formed due to laser ablation have shown inverse relationship. Artificial neural network (ANN) has been employed successfully using LIBS data, to understand the level of irradiation of the SR samples. Overall, the silicone rubber micro-nanocomposite sample S2 filled with micro-ATH and nano Alumina has reflected relatively lesser degradation after being exposed to gamma irradiation, over other test specimens.