Nano Zirconia Research Articles

Analysis and optimization of machining parameters of AZ91 alloy nanocomposite with the Influences of nano ZrO2 through vacuum diecast process

The magnesium alloy composite is a vital material for automotive applications due to its features like high stiffness, superior damping resistance, high strength, and lightweight. Here, the motto of research is to establish the AZ91 alloy nanocomposite with the exposures of 0, 1, 3, and 5 volume percentages (vol%) of nano zirconium dioxide (ZrO2) particles (50nm) through fluid stir metallurgy route associated with 1x105 Pa vacuum die cast process. Exposures on structural morphology, hardness, and impact toughness of composite are analyzed and identified as the nano AZ91 alloy composite enclosed with 5vol% is homogenous particle dispersion, enhanced hardness (97.6HV), and optimum toughness of 21.2J/mm2. However, composite faces machining difficulties due to the hard abrasive particles with higher hardness, resulting in tool wear. This experiment predicts the optimum mill parameters during the end mill operation of magnesium alloy nanocomposite (AZ91/5vol%) by using a tungsten carbide coated end mill cutter to attain the maximum metal removal rate with low surface roughness and tool wear analyzed via the general linear model (GLM) ANOVA approach. The input conditions for end milling operation vary, like feed rate (0.1 -0.4mm/rev), depth of cut (0.05 -0.2mm), and spindle speed (250-1000rpm). During the ANOVA GLM approach, the L16 design experiment is fixed for further interaction analysis. The results predicted by the depth to cut and feed rate were dominant and played a major role in deciding the tool wear, surface roughness, and MRR.

Facile Synthesis and Characterization of Zirconia Nanoparticles in Dental Applications

Scientists and dentists use tiny particles called ZrO2/Nps (Zirconia Nanoparticles) in medicine. In addition, zirconia particles are commonly used in the realm of medicine and dentistry. They are ideal for tooth structure because of their beneficial properties. The objective of this research is to prepare zirconium oxide nanoparticles in a simple and easy way. Nano-zirconium oxide is prepared using the co-precipitation method. The produced powder was diagnosed using tools like X-ray diffraction, microscopy, and spectroscopy, which also analyzed its properties such as X-ray spectroscopy and density measurement. The XRD results confirmed that the powder product has high purity. The crystal size range is 27.97nm. The results match the (JCPDS (ZrO2) sheet No.79-1769). The EDX test revealed the presence of the following elements (Zr–O). The test of SEM (Scanning Electron Microscope) show that the particles nearly spherical and the size was 74.03nm. The Zr–O stretching modes and the Zr–O2–Zr bending modes were confirmed by the FTIR (Fourier transform infrared). The density of ZrO2/Np was measured several times and determined it to be (5.07±0.12 g/cm3).

Response surface study on continuous supercritical hydrothermal synthesis of nano-zirconia: Scale-up from laboratory to industrialization

Commercial interest in nanomaterials and their applications lead to the development of many new methods for mass production. Among them, supercritical hydrothermal synthesis (SCHS) is a highly efficient and environmental-friendly technology. In this work, an advanced industrialized device for SCHS was used to verify the synthesis of nano-zirconia particles. The influencing laws and mechanisms of different material parameters (precursor type, precursor concentration, and pH) and process parameters (reaction temperature, reaction pressure, residence time, and Reynolds number) of nano-zirconia synthesis were studied. For the first time, the state changes of zirconium precursors and the precipitation behavior of nano-zirconia particles were in-situ observed by a high-speed camera. Central composite design (CCD) of response surface methodology (RSM) was adopted to investigate interactive effects of reaction temperature (200–420 °C), reactant concentration (0.01–0.6 mol L−1), alkali ratio (0–5) and flow rate (3–15 mL min−1), with particle size (APS), crystal form ratio (k) and reactant conversion rate (α) serving as response values. The influence of key process parameters follows an order of reaction concentration > reaction temperature > system flow > alkali ratio for APS, alkali ratio > system flow > reaction temperature > reaction concentration for k, and reaction temperature > alkali ratio > system flow > reaction concentration for α, respectively. The optimal process parameters were then obtained and further verified at lab and industrial scale. Zirconia powders with particle sizes of 4.98 nm and 8.74 nm were synthesized, respectively, indicating five hundred times magnification of continuous SCHS of nano zirconia from laboratory to industrialization.

Evaluation of innovative fluroapatite /silicon dioxide modified zirconia nanocomposites coated on Ti–13Nb–13Zr alloy for dental implant application

Dental implants are intended to function as a durable method for replacing missing teeth. A biocompatible dental alloy is used to achieve integration with the jawbone through Osseointegration. This creates a strong base for the implant, allowing it to withstand the mechanical forces generated during biting and chewing. Dental alloys are commonly subjected to various mouth conditions known for their intricate corrosion potential. Corrosion can weaken the structural integrity of the implant, causing issues such as implant loosening, micro-motion at the implant-bone contact, implant fracture, allergic reactions, toxicity, and possible disruption of the Osseo integration process. To improve the alloy's corrosion resistance and biocompatibility, its surface can be altered using nanocomposite materials. The materials provide a protective coating to the alloy, creating a physical barrier that effectively prevents corrosive substances from reaching the underlying bulk material. This study involves modifying the surface of the dental alloy Ti–13Nb–13Zr with Fluroapatite (FAP)/Silicon dioxide (SiO2) modified zirconia (ZrO2) nano composites. The altered surfaces are then studied in simulated body fluid and artificial saliva solutions using in vitro methods. The FAP/SiO2 modified ZrO2 nanocomposites is applied onto a Ti–13Nb–13Zr alloy utilizing Electrophoretic deposition and Dip coating techniques. The coated samples were analysis utilizing FTIR, XRD, and SEM with EDS. Corrosion analysis was carried out on coated and uncoated samples using Electrochemical methods in simulated body fluid and artificial saliva solution. The biocompatibility is assessed using MTT assay, contact angle, and immersion testing in both SBF and Artificial saliva. EIS and corrosion study results show that FAP/SiO2 modified ZrO2 nanocomposites coated Ti13Nb13Zr alloy has high polarization resistance, low corrosion rate, and good charge transfer resistance, indicating excellent corrosion resistance. The contact angle study showed that the surface-modified Ti13Nb13Zr alloy is superhydrophilic, increasing implant surface osseointegration. Cell viability measurements reveal good cell growth, while immersion investigations show calcification, leading to enhanced osseointegration between the implant and its surrounding tissues. hence, it is an excellent material for dental implants application.

Optimized DLP 3D-printed high-resolution nano zirconia-hydroxyapatite scaffold with craniomaxillofacial soft tissue invasion resistance and pro-osteogenic properties via dectin-1/syk inflammatory axis

One major challenge of craniomaxillofacial bone regeneration is the direct contact of subcutaneous fibrous tissue towards bone regenerative region, which results in fast fibroblast invasion and suppression of bone regeneration. Dectin-1, a pattern recognition receptor expressed on activated macrophages, is crucial for directing fibrous invasion. Targeting Dectin-1 and its downstream signaling cascade could be an effective strategy to resist “craniomaxillofacial soft tissue invasion”. Nano zirconia can shelter the essential amino acids of Dectin-1 and was reported to deactivate the inflammation signals. Herein, we succeeded in incorporating nano zirconia into high-resolution 3D hydroxyapatite (HA) scaffolds via modified digital light processing (DLP) technique system. The incorporation of nano zirconia can endow high-resolution HA scaffolds with the capacity of regulating the key structure of extracellular C-type lectin-like domain (CTLD) of dectin-1, proved by computational simulation. This results in inhibiting the dectin-1/syk axis and pro-soft tissue proliferation cytokines production. In vivo experiments further validated the effects of HA/nano zirconia resisting craniomaxillofacial soft tissue invasion and promoting bone regeneration. Our work practices the concept of “soft tissue invasion resisting capacity” via targeting in manipulating dectin-1, which succeeds in attenuating fibrous invasion and craniomaxillofacial bone regeneration. The “soft tissue invasion resisting capacity” could become a valuable biological paradigm of craniomaxillofacial bone biomaterials.

Antibacterial Synergy: Assessing the Impact of Nano Zirconium Oxide Particles in Combination with Selected Antibiotics on Escherichia coli and Klebsiella pneumoniae Isolates from Urinary Tract Infections

Antibacterial Synergy: Assessing the Impact of Nano Zirconium Oxide Particles in Combination with Selected Antibiotics on Escherichia coli and Klebsiella pneumoniae Isolates from Urinary Tract Infections

Clinical Performance and Wear Resistance of Highly Translucent Nano Zirconia Reinforced Glass Ionomer Filling Versus Conventional Resin Composite Restorations in Patients with Proximal Carious Teeth: Randomized Clinical Trial

Aim: This study aimed to evaluate the clinical performance and occlusal wear resistance of nano- zirconia reinforced glass ionomer restorations in comparison to nano-hybrid resin composite restorations in proximal cavities. Material and Method: This randomized clinical trial was conducted on thirty-two patients who had proximal carious lesions in posterior teeth. Participants were randomly allocated into two groups (n=16 for each group) in which they received either; Nano zirconia reinforced glass ionomer restorations (Zirconomer Improved, Shofu, Japan) or Conventional nano hybrid resin composite (Filtek Z250 XT, 3M ESPE, USA), all materials were applied according to manufacturers’ instructions. Restorations were evaluated at baseline (immediately), after six months, and after 12 months by two blinded assessors using modified USPHS criteria measuring (postoperative hypersensitivity, secondary caries, gross fracture, color match, cavo-surface marginal discoloration, marginal integrity, proximal contact and wear resistance). Data was analyzed using Medcalc software, intergroup comparisons between interventions was performed using the Chi-Squared test with statistical significance level set at (P ≤ 0.05) while intragroup at (P ≤ 0.016) after Bonferroni correction, relative risk was used to assess the clinical significance. Results: Intergroup comparison between both materials regarding USPHS criteria and wear resistance have shown no statistically significant difference within different follow up periods; baseline, 6 and 12 months respectively except for the color match shown significant difference with highly translucent nano zirconia reinforced GI. Intragroup comparison within highly translucent nano zirconia reinforced glass ionomer and within conventional resin composite regarding USPHS criteria have shown no statistically significant difference between different followup periods except for the wear resistance shown significant difference within highly translucent nano zirconia reinforced GI. Conclusion: Nano zirconia reinforced glass ionomer and Nano hybrid resin composite have a similar clinical performance and wear resistance after one year follow up.

Antimicrobial Activity of Nanozirconium Oxide.

The goal behind this work is to prepare, characterize, and study the antimicrobial behavior of zirconia (ZrO2) nanoparticles (NPs). Various techniques, such as X-ray diffraction (XRD), were used for studying the mineralogical structure and crystal size. The microstructure and chemical composition of the prepared particles were analyzed using a scanning electron microscope attached with an energy-dispersive X-ray analysis (EDAX) unit. The antagonistic ability against several Gram-negative and Gram-positive bacteria, including Salmonella paratyphi, Pseudomonas aeruginosa, Alcaligenes aquatilis, Escherichia coli, Streptococcus pneumoniae, and Staphylococcus aureus, was assessed using the well diffusion method. The results of XRD and scanning electron microscopy (SEM) analyses revealed that the prepared material exhibited the phase of zirconium nanoparticles with particle sizes ranging between 40 and 75 nm. The antimicrobial test results demonstrated that the inhibitory effect increased with the increase of concentration. The inhibitory effect was more pronounced against Gram-positive bacteria, as indicated by the larger size of the inhibitory zone. At a 9% dimethyl sulfoxide (DMSO) concentration, the inhibitory zone had a diameter of 3.50 mm for S. aureus compared to a diameter of 3.40 mm for S. pneumoniae. The use of zirconium oxide nanoparticles reduced the diameter of the inhibitory zone when tested against S. aureus at a 3% DMSO concentration (0.50 mm diameter) and against S. pneumoniae (0.40 mm diameter). Zirconia nanoparticles were also evaluated for their antifungal activity against several species, including Aspergillus niger, Aspergillus flavus, and Penicillium sp. The size of the inhibitory zone indicated the susceptibility of microorganisms to nanozirconium oxide, resulting in a stronger inhibition of Penicillium sp. at a 100% DMSO concentration (4.50 mm diameter) compared to A. niger and A. flavus (3.00 mm diameter). The results for Penicillium sp. at a 3% DMSO concentration showed a diameter of the inhibitory zone of 0.90 mm, while for A. niger and A. flavus, the diameter was 0.80 mm. Thus, our findings demonstrate that the zirconium oxide nanoparticles possess the capability to reduce the inhibition zone effectively for both bacterial and fungal activities.

Chemical and physical properties of radiopaque Portland cement formulation with reduced particle size.

This study compared the chemical and physical properties of an experimental radiopaque white Portland cement (REPC) with reduced particle size to ProRoot white mineral trioxide aggregate (WMTA). The particle size distribution of experimental Portland cement (EPC) was examined, and then nano-zirconium oxide (nano-ZrO) was added to produce REPC. Chemical analysis, initial setting time, pH values, and push-out bond strength were evaluated. Results showed that REPC had smallest particle size (354.5±26.45 nm), while PC had the largest (1,309.67±60.54 nm) (p<0.05). Differences in chemical composition were observed. REPC exhibited shorter setting time (32.7±0.58 min) compared to WMTA (131.67±2.89 min) and PC (163.33±2.89 min) (p<0.05). All groups showed alkaline pH (p<0.05). REPC demonstrated the highest push-out bond strength (22.24±4.33 MPa) compared with WMTA (15.53±3.26 MPa) and PC (16.8±5.43 MPa) (p<0.05). This cost-effective PC formulation reduced the setting time and increased the push-out bond strength while maintaining the alkaline properties of the original cements.

Evaluation and Experimental Investigation on A356.1 Aluminum Composite Reinforced with Zirconium Oxide Nano Metal Matrix Composites through Stir Casting technique

Because of their durability, aluminum composites are employed in self-propelled industries. Despite their superior malleability and formability, high electrical and thermal conductivity, and low densities, aluminum alloys have several drawbacks when used in engineering appliances due to their strength and mechanical behavior. The preparation of nanoparticles by means of the combustion mixture method is presented in this paper. ZrO2 nanoparticles are added to A356.1 aluminum alloy by stir casting at weight percentage ratios of 1.0, 2.0, 3.0, and 4.0% while the mixture is continuously stirred at 100 rpm. PXRD was used to characterize the produced nanoparticles, revealing their elemental compositions. Results from hardness testing with a Brinell hardness apparatus and tensile testing with a tensometer showed that the mechanical characterization of Nano Metal Matrix Composites (NMMCs) with 4.0 weight percentage is superior.

Preparation and characterization of novel nano-tricalcium silicate-58s bioactive glass-based root canal sealer

Introduction: Calcium silicate-based root canal sealers are gain significant interest in the recent endodontic treatment, but the high solubility and long setting time are the most shortcoming. Therefore, this study aimed to develop new nano-tricalcium silicate-58s bioactive glass (BG)-based root canal sealer with phosphate-buffered saline (PBS) as a liquid precursor, as well as to evaluate the hydration reaction of the newly prepared sealer. Materials and Methods: Different formulae were prepared by adding nano-zirconium dioxide (ZrO2) and 58s BG to the tricalcium silicate (C3S) at different concentrations. Furthermore, two types of liquid were used as precursors (PBS and distilled water). Then after, the setting time and solubility were evaluated for each prepared formula. Statistical analysis was performed using analysis of variance and Tukey tests. The formula that had the best properties was characterized by X-ray diffraction and Fourier transform infrared spectroscopy. Results: It was found that the ZrO2 at 25%, BG at 30%, and the use of PBS as a liquid improved the physical properties of the prepared sealer. Results indicated that the main hydration reactions by products for the best formula were noncrystalline calcium silicate hydrate, crystalline Ca(OH)2, CaCO3, Ca(H2PO4)2, Ca3(PO4)2, and hydroxyapatite. Conclusions: The experimental formula that composed mainly of 45% C3S, 25% ZrO2, and 30% BG as a powder and PBS as a liquid precursor had superior properties, which is in line with the American Dental Association specification.

Tribological behaviour of thermally sprayed nano zirconia coating on AA7075

Tribological behaviour of thermally sprayed nano zirconia coating on AA7075

The support effect on the performance of a MOF-derived Co-based nano-catalyst in Fischer Tropsch synthesis.

The catalyst plays a central role in the Fischer-Tropsch synthesis (FTS) process, and the choice of catalyst support significantly impacts FTS catalyst performance by enhancing its attributes. In this study, the effects of utilizing various metal oxides-CeO2, ZrO2, and TiO2-on a cobalt-based FTS nanocatalyst are investigated by evaluating the catalyst's reducibility, stability, syngas chemisorption, intermediate species spillover, charge transfer, and metal-support interaction (MSI). This evaluation is conducted both theoretically and experimentally through diverse characterization tests and molecular dynamics (MD) simulations. Characterization tests reveal that the ceria-supported catalyst (Ceria Nano Catalyst, CNC) demonstrates the highest reducibility, stability, CO chemisorption, and spillover, while the zirconia-supported catalyst (Zirconia Nano Catalyst, ZNC) exhibits the highest hydrogen chemisorption and spillover. The MD simulation results align well with these findings; for instance, ZNC has the lowest hydrogen adsorption enthalpy (ΔHAds.), whereas CNC has the lowest ΔHAds. for CO. Additionally, MD simulations indicate that the titania-supported catalyst (Titania Nano Catalyst, TNC) possesses the highest MSI value, closely resembling that of ZNC, albeit with a minor difference. The TNC catalyst's performance in other tests is also similar to that of ZNC. Finally, FTS performance tests illustrate that the ZNC catalyst achieves the highest CO conversion at 88.1%, while the CNC catalyst presents the lowest CO conversion at 82.2%. Notably, the CNC catalyst showcases the highest durability, with only a 4.4% loss in CO conversion and an 8.55% loss in C5+ yield after 192 h of operation.

Green color emitting pure cubic zirconia nano phosphor synthesized by solution combustion technique

Green color emitting pure cubic zirconia nano phosphor synthesized by solution combustion technique

Effect of nano hybrid additives on low velocity impact responses of aramid composite plates: example of CNT and ZrO2

Aramid reinforced composites are advanced materials that are widely used in many industrial applications thanks to their combination of high strength and lightness. Nano additives are of great importance for improving the mechanical properties of aramid reinforced composites and reducing costs. In this paper, multi-walled Carbon Nanotube (CNT) and Zirconia (ZrO2) nano hybrid additives were used to determine the effect on the mechanical characterization of aramid composite plates. Therefore, low velocity impact responses of aramid fiber reinforced composites were investigated by adding ZrO2 and CNT nano hybrid additives to the Polives 701 polymer vinylester resin matrix. Low velocity impact tests were carried out at 10 J and 15 J. As a result of the experiments, the effects of nano hybrid additives on the impact absorption properties of aramid composite plates were determined. By determining the maximum force, displacement and time values, the effect of CNT and ZrO2 nano hybrid additives on the impact resistance of the composite plates was analyzed. In addition, it contributed to the development of composite materials used in industrial applications by providing information on increasing the performance of composite materials by using nano additives. As a result of this study, it was determined that the strength of the composite material increased proportionally when the CNT additive was used, and the material became embrittled when the ZrO2 additive was used.

Intensification of bio-synthesis of zirconium oxide (ZrO2) nanoparticles derived from novel Crescentia Cujete fruits: Effects on diesel engine characteristics powered by waste engine oil methyl ester-diesel blend

The current Study focuses on a biosynthesis of Zirconium Oxide nano-additives (ZrO2) from the novel Crescentia Cujete fruits, which is simpler, non-hazardous, and ecologically friendly technique when compared to the complex chemical methods. The first phase discussed the characterization of Zirconium oxide nano-particles. Fourier Transform- Infra Red analysis revealed that phenolic compounds with OH stretching vibrations caused the compound's absorption peak at 3434 cm−1. Scanning Electron Microscope analysis revealed the existence of trigonal and spherical forms in the green ZrO2 nanocomposite. The UV–Visible spectrum analysis of the Calabash fruit extract revealed a prominent maximum absorbance at 361nm. The second phase examined the effects of using biodiesel made from used engine oil along with a bio-synthesized nano-additives zirconium oxide on the efficiency and emission characteristics of a diesel engine. The experimental results revealed that Zirconium oxide nano-additives reduced brake specific fuel consumption (BSFC) in waste engine oil methyl ester (WEOME25) fuel blend. WEOME25 with ZrO2 nano-particles increases BTE by 1.7% at 50ppm, 3.41% at 75ppm, and 3.91% at 100ppm. WEOME25+ZrO2 at 50ppm, 75ppm, and 100ppm increased cylinder pressure by 1.38%, 2.21%, and 1.87%, respectively. Zirconia nano additions boost combustion and reduce HC, CO and Smoke emissions except NOx emission.

Concurrent reduction of the fume and Cr (VI) concentrations of inhalable and respirable particle using a new covered stainless-steel SMAW electrode

In this work, a new covered electrode was developed for a SMAW process by the concurrent use of two fume reduction techniques viz; nano-arc stabilizer coating on welding core wire and nano-particle substitution on the welding flux. The experimental core electrode wires were coated with nano-zirconium to improve the electrode’s arc stability and reduce the effective oxygen concentration in the arc atmosphere. To further improve the arc stability, size-reduced synthetic rutile was mixed with the electrode flux. Total fume formation from experimental and conventional electrodes was evaluated and compared. Compared to the conventional electrode, the experimental electrode showed an 82 % reduction in fume production and an 85 % reduction in breathing zone concentration. The combined effect of nano zirconia and size-reduced synthetic rutile increased the reactivity of the arc atmosphere and favoured the reduction of inhalable and respirable fume mass concentration by improving arc stability and reducing spatter formation. The experimental electrodes showed a significant reduction in Cr(VI) concentration in fume up to 68 %. The Cr (VI) concentration in the inhalable and respirable fumes was also reduced by 36 % and 52 % in that order.

The impact of zirconia nanoparticles on the mechanical characteristics of 7075 aluminum alloy

Abstract In numerous engineering applications, metal matrix composites strengthened by ceramic particles have played an important role. For this purpose, an aluminum (Al 7075) nanocomposite has been fabricated, and nano-zirconium oxide of particle size 40 nm (0, 0.8, 1.6, and 2.4) wt% reinforced Al 7075 alloy was produced using a stir-casting process. The effect of ZrO2 NPs loading on mechanical properties along with the detailed characterization were demonstrated. The performance of Al with ZrO2 nanocomposite was investigated by Vickers hardness tester, scanning electron microscopy, energy-dispersive X-ray, compression test, Lee’s disc, and Shore D instruments were utilized to determine the hardness, structural morphology, composition of the elements, Young’s modulus, thermal conductivity, and roughness values of the samples, respectively. The hardness (120.3–177) HV, compression strength (624.2–878.6) MPa, yield modulus (38–70) MPa, surface roughness (0.876–0.606) µm, thermal conductivity (2.0–2.39) W/m2 °C improved by increasing the wt% of ZrO2 NP reinforcement particles. The implication of these findings shows that 5 wt% nano-ZrO2-reinforced Al 7075 composites yielded better performance than pure Al 7075 alloy. To sum up, this investigation demonstrated that the ZrO2 reinforcement enhanced the mechanical properties of Al 7075.

Optimization on hardening process parameters of alumnium alloy 7075 based composites using gra approach

Aluminum Metal Matrix Composites (AMMCs) play a vital role in various industries, including aerospace, aviation, maritime, transportation, and automotive, owing to their remarkable mechanical strength, resistance to corrosion, and tribological performance. The age-hardening process for AA7075-based Metal Matrix Composites is essential to meet specific performance requirements, improve material properties (enhancing mechanical properties, tailoring material performance, improving wear resistance, reducing weight, enhancing corrosion resistance, extending service life), and enhancing the overall suitability of these materials for a wide range of demanding applications. The objective of this study is to improve the mechanical and tribological characteristics of AA7075-based composites by utilizing the age-hardening process, rather than introducing additional reinforcements to the base material. Aluminium Alloy 7075 (AA7075) is selected as the matrix material due to its significant need for improvement in mechanical, corrosion, and tribological properties. Nano zirconium dioxide (ZrO2) is chosen as the reinforcement to meet the property requirements of AA7075 for various applications The composites comprising AA7075 alloy and varying weight percentages of ZrO2 (x = 0, 5, 10, 15, and 20) are fabricated using the stir casting method. The fabricated composites are subjected to tensile strength and density tests to determine the optimal combination of AA7075-based composites by employing the Archimedes principle and a Universal Testing Machine, respectively. The manufactured AA7075-based composites were subjected to EDAX and SEM tests to determine the wt% presence of elements of reinforcement and matrix material by employing the S 3000 - HITACHI model. The stir-cast AA7075-based composites were further subjected to hardening under different conditions to enhance their required properties. Age hardening was performed with the help of a Muffle furnace. The input parameters for hardening were age-hardening temperature (200, 300, and 300 °C), hardening duration (90, 180, and 270 min), and cooling environments (Furnace, water, and atmosphere). The chosen response parameters were micro hardness and wear loss. The microhardness and wear resistance of these composites were assessed using a Vickers hardness tester and a Pin-on-Disc testing apparatus. The optimization was carried out using Grey Relational Analysis (GRA). The confirmation test was conducted to determine density, Ultimate Tensile Strength (UTS), micro hardness, and wear loss. The AA7075/15 wt% ZrO2 composite exhibited a uniform distribution of zirconium dioxide in the AA7075 matrix material among the other manufactured composites. The AA7075/15 wt% ZrO2 exhibited higher density of 2.889 g cm−13 and UTS of 316 MPa than other combinations of AA7075 composite materials. Increasing the heating temperature and duration enhanced the micro hardness and wear resistance. Higher micro hardness and wear resistance were obtained with furnace cooling compared to other cooling environments. The optimized age-hardening process parameters are hardening temperature (400 °C), hardening duration (270 min), and cooling environment (Furnace cooling). The enhanced mechanical and tribological properties result from precipitate formation and density enhancement. The confirmation test for the combination specimen yielded higher density, UTS, micro hardness, and lower wear loss values, which are 2.896 g/cm3, 325 MPa, 138 HV, and 27 mg, respectively.

Influence of nano zirconia on the mechanical and durability properties of high-performance concrete containing nano-silica

High Performance Concrete (HPC) was prepared by reinforcing with hybrid nanoparticles such as nano-SiO2 and nano-ZrO2 and the flowability, strength and durability of the concrete was investigated. Slump study showed that the prepared HPC displayed a slump loss with the addition of hybrid nanoparticles due to the absorption of water by hybrid nanoparticles. Experimental results showed that the inclusion of 10% nano-SiO2 and 5% nano-ZrO2 hybrid nanoparticles (mix code M5) enhanced the compressive strength of concrete and exhibited a maximum of 50.12 MPa and 76.4 MPa at 7 days and 28 days of curing due to the reduction of pore volume. Split tensile strength followed the same trend of variation as compressive strength and the mix code M5 showed the maximum split tensile strength of 5.33 MPa and 7.08 MPa cured at 7 days and 28 days respectively. Flexural study resulted that the mix code M5 exhibited a maximum flexural strength of 5.73 MPa and 7.38 MPa cured at 7 days and 28 days respectively owing to the restriction of crack ignition by reinforced hybrid nanoparticles. Rheological study reported that all the prepared concretes lost the weight by less than 1% and the chloride attack displayed maximum weight loss of 4% whereas alkaline attack showed less weight of concrete.