Aluminum Nitride Content Research Articles

Effect of aluminium nitride (AlN) particles addition on mechanical and tribological properties of aluminium matrix composites

Aluminum matrix composites (AMCs) are the most popular materials for use in a variety of industries, including the aerospace, automotive, and military sectors due to its advantageous features. In this study, the influence of AlN particles insertion on the morphology and mechanical properties were reported.Stir casting method was engaged to manufacture the AA2017 based composites reinforced with x wt.% of AlN particles (x = 0, 5, 10 and 15 wt%).The developed composites were undergone to conduct the tensile test, compression test, and hardness test as per ASTM standard. Microstructure of the proposed composites clearlyexposedthe homogeneous circulation of AlN particles and also no agglomeration formed within the matrix. The results showed the tensile strength (TS) compressive strength (CS)and hardness have drastically improved with insertion of AlN content in the base matrix. As a result, the better properties can be achieved in 15 wt% of AlN particles reinforced AA2017 matrix composite.

Thermal conductivity of epoxy resin films doped with a polythiophene/graphene complex or aluminum nitride

AbstractPolymer composites with thermal conductivity are attractive for heat dissipation in electronic devices. We prepared epoxy resin‐based composite films filled with polythiophene [poly(3‐hexylthiophene‐2,5‐diyl)] (P3HT)/graphene complex or aluminum nitride (AlN). The composite films were characterized by electron microscopic observation, thermogravimetric analysis, and thermal conductivity measurements. The addition of a small content of P3HT/graphene complex (<1 wt%) increased both the out‐of‐plane and in‐plane thermal conductivities of the epoxy resin. The addition of AlN also increased thermal conductivity, but ≥40 wt% was required to obtain thermal conductivity comparable with that of an epoxy resin film doped with 0.9 wt% P3HT/graphene complex. The present results illustrate the potential of P3HT/graphene complexes as fillers for improving the thermal conductivity of epoxy resins without affecting their insulating properties.Highlights Polythiophene/graphene fillers increased epoxy resin films' thermal conductivity. To raise the thermal conductivity of epoxy resin films high AlN content was needed. In‐plane/out‐of‐plane epoxy resin films' thermal conductivities were evaluated.

Effect of AlN content on microstructure and properties of SiAlON ceramics prepared via vat photopolymerization

To date, the application of additive manufacturing techniques in fabricating SiAlON ceramics with intricate geometries has been limited. This investigation demonstrates the synthesis of SiAlON ceramics by integrating silicon nitride (Si3N4) powders with variable proportions of aluminum nitride (AlN) utilizing the vat photopolymerization (VPP) approach. The effects of AlN content on the properties of SiAlON ceramic slurries, green bodies, and sintered parts were systematically investigated. Notably, the slurry's viscosity decreases progressively with an increase in AlN, aligning with VPP printing prerequisites. Additionally, the curing depth of the slurry enhanced proportionally with AlN augmentation, elevating from 21 μm to 44 μm at an energy exposure of 800 mJ/cm2, with the pivotal addition being 15 vol% AlN, where optimal properties were achieved. The zeniths of flexural strength, bulk density, relative density, and thermal conductivity were recorded at 385.66 ± 22.63 MPa, 3.34 ± 0.09 g/cm3, 96.22 ± 2.55 %, and 37.4 ± 0.31 W m−1 K−1, respectively. The fabrication of SiAlON ceramics with complex configurations was successfully realized, heralding a novel methodology for future SiAlON ceramic production.

High-temperature synthesis of cast vanadium nitrides and aluminum oxynitrides

This paper presents experimental results concerning the one-step preparation of cast divanadium nitride and aluminum oxynitride (AlON) by high-temperature synthesis under 5 MPa of N2 from green mixtures containing vanadium oxide, aluminum, and aluminum nitride. It was shown that the mixtures with a wide range of component ratios are capable to burn with the temperature exceeding the melting point of the final products, divanadium nitride and aluminum oxynitride, that makes it possible to obtain them in the form of a melt with subsequent separation of vanadium nitride (lower ingot) and aluminum oxynitride (upper ingot). The resulting products had no cohesion and were easily separated from each other. Variation in the content of aluminum nitride in the charge markedly affected the synthesis process, phase composition, and microstructure of the target products. The content of excess aluminum nitride in the starting mixture α = 10% was found to be optimum on a yield/composition of the target products.

Structure, Phase Composition, and Mechanical Properties of ZK51A Alloy with AlN Nanoparticles after Heat Treatment

The paper studies the influence of the content of aluminum nitride nanoparticles on the structure and mechanical properties of the ZK51A magnesium alloy. The microstructure investigations with optical and electron microscopy show that 1 wt.% AlN promotes the best grain refinement and size distribution. According to tensile strength testing of the ZK51A alloy, grain refinement is not a dominating mechanism in the property improvement of the alloy after heat treatment. The maximum values of mechanical parameters are achieved at the lowest (0.1 wt.%) content of aluminum nitride. The main mechanism of mechanical characteristics increase with the addition of AlN nanoparticles is dispersion hardening.

Sustainable Improvements in Mechanical and Tribological Properties of AA2017-Aluminum Nitride Composites: A Comprehensive Investigation and Numerical Analysis

An AA2017-aluminum nitride composite was created through stir casting, and its tribological properties, like hardness and wear rate were examined by varying the aluminum nitride content from 5% to 15%. A numerical model was established to predict the wear rates of aluminum metal matrix composites (MMCs), and the accuracy of the model was confirmed through an analysis of variance (ANOVA). The findings demonstrated that the addition of aluminum nitride to AA2017 resulted in improved mechanical and wear characteristics for the composites. Furthermore, the utilization of sustainable materials and manufacturing techniques underscores the potential for environmentally responsible engineering solutions in material science and manufacturing processes. Aluminum nitride emerged as a critical component in enhancing the wear resistance of the metal matrix composites, contributing to their overall durability and sustainability.

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.

Influence of the Addition of Sialon and Aluminum Nitride Fillers on the Photocuring Process of Polymer Coatings

This article presents the results of a study on polymer coatings containing poly ethoxylated bisphenol A diacrylate (Bis-AEA10) with aluminum silicon nitride oxide (Sialon) and aluminum nitride (AlN). The polymer coatings were obtained by the photopolymerization technique. Investigations were carried out to determine the effect of the AlN and Sialon content on the UV-curing kinetics, as well as on the mechanical (hardness), thermal (Tg, thermal stability), physicochemical (water contact angle), and structural properties of the polymer coatings. Polymerization rates were characterized as functions of double-bond conversion using the photo-Differential Scanning Calorymetry technique (photo-DSC). The results obtained showed that a small addition of sialon filler (3–5 wt.%) to Bis-AEA10 increases the photopolymerization rate of the varnish, while the addition of more Sialon decreases the rate of photopolymerization. However, for the systems containing AlN filler, the maximum polymerization rate was observed for samples containing 10 wt.% filler. In the case of a varnish composition containing AlN, the maximum polymerization rate is characterized by the system containing 10 wt.% of AlN. This shows that the AlN filler has a good influence on the polymerization process. In either case, the final double bond conversion was high (80%–95%). Mechanical tests have shown that introducing the filler into the polymer matrix increases its hardness. The content of Sialon and AlN in the coatings causes an increase (up to 4–5 wt.%) and a decrease (>4–5 wt.%) in the glass transition temperature. The effect of the addition of fillers on the physicochemical properties of the coating surface has also been investigated and characterized by the water contact angle method. The addition of 20 wt.% Sialon and AlN increased the contact angle of the samples by approximately 40% and 31%, respectively, resulting in coatings with hydrophobic surface properties.

Effects of Additive and Roasting Processes on Nitrogen Removal from Aluminum Dross

Taking high nitrogen aluminum dross as the research object, the effects of the additives sodium carbonate and cryolite and the roasting process on the denitrification effect of aluminum dross were studied. The principle of additive denitrification was studied by XRD, SEM and TG-DSC. The experimental results show that sodium carbonate and cryolite can quickly reduce the content of aluminum nitride in aluminum dross. The optimum denitrification process parameters were also obtained simultaneously. When the mass ratio of cryolite to aluminum dross was 0.4, the roasting temperature was 900 °C, and the roasting time was 3 h, the denitrification degree could reach 96.19%. When the mass ratio of sodium carbonate to aluminum dross was 0.8, the roasting temperature was 1000 °C, and the roasting time was 4 h, the denitrification degree could reach 91.32%. This study provides a reference for the non-harmful treatment of high nitrogen aluminum dross.

Synthesis of Cubic Aluminum Nitride (AlN) Coatings through Suspension Plasma Spray (SPS) Technology

Thermal spraying of aluminum nitride (AlN) is a challenging issue because it decomposes at a high temperature. In this work, the use of suspension plasma spray (SPS) technology is proposed for the in situ synthesis and deposition of cubic-structured AlN coatings on metallic substrates. The effects of the nitriding agent, the suspension liquid carrier, the substrate materials and the standoff distance during deposition by SPS were investigated. The plasma-synthesized coatings were analyzed by X-ray diffraction (XRD), optical microscopy (OM) and scanning electron microscopy (SEM). The results show higher AlN content in the coatings deposited on a carbon steel substrate (~82%) when compared to titanium substrate (~30%) or molybdenum (~15%). Melamine mixed with pure aluminum powder produced AlN-richer coatings of up to 82% when compared to urea mixed with the Al (~25% AlN). Hexadecane was a relatively better liquid carrier than the oxygen-rich liquid carriers such as ethanol or ethylene glycol. When the materials were exposed to a molten aluminum–magnesium alloy at 850 °C for 2 h, the corrosion resistance of the AlN-coated carbon steel substrate showed improved performance in comparison to the uncoated substrate.

Ultrafine electrospun fiber based on ionic liquid/AlN/copolyamide composite as novel form-stable phase change material for thermal energy storage

A novel form-stable phase change material (FSPCM) based on ionic liquid/aluminum nitride/copolyamide composite were fabricated from electrospinning approach. The ionic liquid 1-hexadecyl-3-methylimidazolium bromide (IL) was chosen as phase change materials while nano aluminum nitride (AlN) and copolyamide 6/12 (CoPA) were chesen as additive and supporting matrix, respectively. The surface morphology and heat storage property had been systematically investigated by Scanning Electronic Microscopy (SEM) and Differential Scanning Calorimetry (DSC), respectively. Results showed that the diameter of the phase change fibers are 0.92–1.07 μm and was influenced by the IL and AlN content. With 57 wt% of IL and 5 wt% of AlN, the composite fiber achieved a fusion enthalpy of 86.4 J/g and the thermal conductivity was increased by 165.2% compared to that of IL/CoPA. Thermogravimetric Analysis (TGA) and thermal cycle test also indicated a good thermal stability and reusability of the composite fiber. Furthermore, Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD) analyses indicated that new hydrogen bonds between IL and CoPA were formed in the composite and showed a significant effect on the thermal performance of the composite fibers. The electrospun composite fiber based on ionic liquids can be applied as form-stable phase change material in thermal energy storage and temperature regulation.

Structure and Properties of a Tool Material Prepared by Hot Pressing from the Exothermic Mixture of Cr2O3–AlN Micropowders

Abstract—The results of studying the structure of materials with maximum hardness and fracture toughness values, which are obtained by hot pressing of mixtures of commercial Cr2O3 micro powders with 15, 25, and 35 wt % AlN, are reported. It is shown that these materials have the dispersed heterophase structure regardless of the composition of the initial mixture. It includes new phases, namely, a matrix of solid solutions of variable compositions of the (Cr1 – x–Alx)2O3 (0 < x < 0.9) type and dispersed inclusions based on Cr2N. The content and size of the latters increase with an increase in the content of aluminum nitride in the starting mixture. The ratio of Al and Cr in the solid solution depends on the composition of the starting mixture. The content of aluminum present in dispersed inclusions based on Cr2N increases from 1.8 to 4 wt % with an increase the amount of aluminum nitride in the original mixture from 15 to 35 wt %. The hardness and fracture toughness of the materials are reduced by 2.4 GPa and 1.1 MPa m1/2, respectively. It is shown that the cutting blades obtained from the Cr2O3–15AlN mixture are competitive, under conditions of fine grinding of carbon steel ShKh15 (HRC 62), to the blades of traditional CC650 ceramics most widespread today when scored by the price–quality criterion.

Study of optical and structural properties of sputtered aluminum nitride films with controlled oxygen content to fabricate Distributed Bragg Reflectors for ultraviolet A

Aluminum nitride (AlN) films with controlled oxygen content were deposited on silicon substrates, and optical properties studied with dependency on film morphology. Combinations of argon (Ar) and nitrogen (N2) gases were used in RF magnetron sputtering of an AlN target. The resulting refractive index ranging from 1.6 to 2.0 at 400 nm was tuned by controlling the sputter gas flow rate ratio of Ar and N2. The resulting refractive index is associated with density and aluminum nitride content of the thin films. Distributed Bragg Reflectors (DBRs) optimized for ultraviolet-A reflectivity were fabricated with pairs of alternating AlN thin films using an explicit combination of low-n and high-n to further investigate the thin film optical properties. The effect of structural transformation in the DBR stack on the progress of optical properties was studied. The DBRs exhibit a negligible extinction coefficient, utilizing precise control of oxygen incorporation with one sputtering target.

Plasma Chemical Synthesis of Aluminum Nitride Nanopowder

We studied in detail the process of producing nanosized aluminum nitride using inductively coupled nitrogen plasma from micron powder of pure aluminum. The phase and granulometric composition of the obtained nanopowders, as well as their morphology, was studied. The influence of various parameters (initial components, gas flow rates, feed rate of the initial powder, etc.) on the synthesis result is determined. Received nanodispersed Al-AlN powder with particle sizes up to 300 nm and aluminum nitride content from 11.6 to 48.8%.

Experimental investigation and characterization of brass – AlN composites synthesized using powder metallurgy technique

This paper is focused on the synthesis of brass–AlN composite based on powder metallurgy technique. By varying the weight percentages (0, 4, 8, 12) of aluminium nitride (AlN) as reinforcement. The high energy ball milling are used the brass-AlN composite. The green cylindrical compacts were produced by hydraulic press. In addition the green compacts are sintered on 1 h at 800 °C in electric muffle furnace under controlled argon atmosphere. The results show that the increase in weight percentage the AlN content of the brass matrix composite increases the density, hardness, strength coefficient of composite and decreases the porosity.

Manipulating thermal conductivity of polyimide composites by hybridizing micro- and nano-sized aluminum nitride for potential aerospace usage

Electrically insulating yet thermally conductive polymer-based composites are highly sought after in aerospace field. In this work, for the first time, electrically insulating but thermally conductive polyimide (PI) composites are fabricated by simultaneously incorporating micro- and nano-sized aluminum nitride (AlN) particles via a simple, economic, and scalable method of ball milling and subsequent hot-pressing process. The thermal conductivity, dielectric, and mechanical properties of the PI composites depend on the ratio of micro-sized AlN (m-AlN) to nano-sized AlN (n-AlN) and the total content of AlN in the PI composites. The thermal conductivity of the PI composites with 40 wt% m-AlN and 20 wt% n-AlN is 1.5 ± 0.05 W·m−1·K−1, which is 10 times higher than that of bare PI. The PI composites hold a great potential in aerospace industries.

Thermal conductivity and dielectric properties of PEDOT:PSS-AlN filler reinforced water-soluble polymer composites

Abstract Poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonic) (PEDOT:PSS) surface modification of aluminum nitride (AlN) fillers and the effects on thermal conductivity and dielectric properties of polyurethane (PU) based composites are investigated in this study. The compositions, microstructure, thermal stability, thermal conductivity, dielectric properties and volume resistivity of the PU based composites were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetry (TGA), optical thermal analyzer (OTA), impedance analyzer (IA), respectively. It was observed that the thermal conductivity and thermal stability of the PU composites increased with increasing AlN content. After proper processing, the AlN particles could form a continuous dispersion, which would form a thermally conductive pathway within the polymer matrix. By adding 0–50 wt% AlN particles, the PU composites thermal conductivity was increased from 0.209 to 0.476 W/m-K. Furthermore, the thermal conductivity can be promoted to 0.764 W/m-K using PEDOT:PSS surface modification. The dielectric properties of the composites can also be adjusted by PEDOT:PSS surface modification. The dielectric constant of the PU based composites was increased from 7.58 to 400 at 10 kHz by adding 0–3 wt% PEDOT:PSS, which can act as an attractive candidate material for packaging, dielectric and embedded capacitors.

Aluminum nitride–filled elastic silicone rubber composites for drag reduction

This study presents aluminum nitride/silicone rubber composite as a drag reduction material, inspired by the boundary heating drag reduction mechanism of dolphin skin. Aluminum nitride was added as a thermal conductive filler at weight fractions of 16.67, 21.05, and 28.57 wt% to pristine silicone rubber. Tests of the thermal conductivity and tensile properties showed that the thermal conductivity of all three aluminum nitride/silicone rubber composites were increased 27.9%, 41.4%, and 43.7% than that of the pristine silicone rubber, and the elastic modulus of the composites was increased with the aluminum nitride content. Droplet velocity testing, which can reflect the drag reduction mechanism of the heating boundary controlled by the aluminum nitride/silicone rubber composites, was performed between all three aluminum nitride/silicone rubber composites and pristine silicone rubber. The results showed that the droplet velocity of all three aluminum nitride/silicone rubber composites were higher than pristine silicone rubber, implying that the composites had a drag-reducing function. In terms of the drag-reducing mechanism, the heat conductivity performance of the aluminum nitride/silicone rubber accelerates the heat transfer between the aluminum nitride/silicone rubber composite surface and droplet. The forces between the molecules and droplet dynamic viscosity are reduced, which result in drag reduction. The application of aluminum nitride/silicone rubber composite to control fluid medium will have important value for fluid machinery.

Influence of aluminium nitride as a foaming agent on the preparation of foam glass-ceramics from high-titanium blast furnace slag

To effectively reuse high-titanium blast furnace slag (TS), foam glass-ceramics were successfully prepared by powder sintering at 1000°C. TS and waste glass were used as the main raw materials, aluminium nitride (AlN) as the foaming agent, and borax as the fluxing agent. The influence of the amount of AlN added (1wt%–5wt%) on the crystalline phases, microstructure, and properties of the produced foam glass-ceramics was studied. The results showed that the main crystal phases were perovskite, diopside, and augite. With increasing AlN content, a transformation from diopside to augite occurred and the crystallinity of the pyroxene phases slightly decreased. Initially, the average pore size and porosity of the foam glass-ceramics increased and subsequently decreased; similarly, their bulk density and compressive strength decreased and subsequently increased. The optimal properties were obtained when the foam glass-ceramics were prepared by adding 4wt% AlN.

Synthesis of Al nanoparticles and Al/AlN composite nanoparticles by electrical explosion of aluminum wires in argon and nitrogen

During the electrical explosion of aluminum wires in argon and nitrogen, Al nanoparticles and Al/AlN composite nanoparticles were synthesized. The as-prepared samples were characterized by transmission electron microscopy, energy dispersive X-ray microanalysis, X-ray diffraction and Brunauer–Emmett–Teller specific surface area measurements. The parameters of the electrical explosion of wires and the gas medium influenced the average size of the nanoparticles and the content of aluminum nitride in the powder. A nanoparticle formation mechanism caused by the coagulation of the primary particles generated in the early stages of the electrical explosion of the wires has been proposed.