Mechanical Alloying Technique Research Articles

Phase prediction, densification, and microstructure of AlCrFeNi(TiO2)x high entropy alloy composite fabricated by spark plasma sintering

This study incorporates the knowledge of empirical calculation and computational concepts using Thermo-Calc as a design guide to develop AlCrFeNi high entropy alloy (HEA). Subsequently, a novel AlCrFeNi HEA composite consisting of varying weight percentages (wt%) of TiO2 reinforcements is synthesized using mechanical alloying (MA) and spark plasma sintering (SPS) techniques. Our work investigated the role of TiO2 reinforcement on the densification behavior, phase changes, microstructure, and properties of AlCrFeNi HEA. The phase diagram was constructed using Thermo-Calc software. Powder densification during SPS was analyzed using obtained sintering data. The samples were characterized using Xray Diffraction (XRD) and Scanning Electron Microscopy (SEM) techniques. The density and micro-hardness were evaluated. The result shows that the densification during SPS is dependent on kinetic mechanisms such as melt diffusion, surface diffusion, and plastic flow. Phases of the disordered BCC phase (rich in FeCr) and ordered B2 phase (rich in NiAl) were found in the AlCrFeNi HEA. The phases were consistent with the prediction using thermo-calc software. The BCC phases in the AlCrFeNi are retained regardless of the addition of TiO2 particles but with the diffusion of Ti with O atoms fitting into the interstitial sites in the BCC and B2 lattice. The microstructure verified the homogeneous distribution of the TiO2-rich phase within the BCC and B2 phases of the AlCrFeNi HEAs. The density decreases with the adding TiO2. The hardness of reinforced AlCrFeNi is enhanced from 537.24 Hv to 752.74 Hv with an increment of TiO2 reinforcement from 0 to 8 wt%. TiO2 particles acted as impediments to the mobility of dislocation, thereby increasing the resistance to deformation of HEA composites during micro indentation.

Dense nanocrystalline ReB2 bulk with ultrahigh hardness

Microcrystalline ReB2 with a high hardness of 48 GPa measured under a small load of 0.49 N has been reported as a superhard material. Nanocrystalline ReB2 is expected to achieve better mechanical properties than its microcrystalline counterparts. Here we report dense nanocrystalline ReB2 bulks synthesized by modified mechanical alloying and high-pressure sintering techniques. The modified mechanical alloying technique reduces the content of WC impurity from 7.75 wt% to 1.59 wt% in as-synthesized nanocrystalline ReB2 powders with an average grain size of 6.6 ± 2.0 nm. The extrinsic high-pressure (6 GPa) and the intrinsic nanocrystalline structure greatly promote the densification process of the ReB2 bulks during sintering. Our optimized nanocrystalline ReB2 bulk is ∼99% dense and with an average crystallite size of 40 nm, resulting in a high hardness of ∼33 GPa under a load of 9.8 N and indentation fracture toughness of ∼5 MPa m1/2. The high hardness can be ascribed to the synergistic effect of high density and nanocrystalline structure of ReB2 bulks. This work provides promising strategies to largely enhance the mechanical properties of different ceramics for practical applications.

Oxides dispersion-strengthened (ODS) FeCoNiCuZn high entropy alloys through different rare earth elements: Synthesis, structural, physical, and experimental radiation transmission properties

The oxide dispersoids within ODS alloys can act as sinks for radiation-induced defects, such as vacancies and dislocation loops, effectively reducing their mobility and preventing their accumulation. This property is crucial for HEAs employed in radiation-intensive environments, such as nuclear reactors. The objective of this research is to examine the impact of rare earth elements (REE) such as Y2O3, Er2O3, Pr2O3, and Sm2O3, on Oxides Dispersion-Strengthened (ODS) FeCoNiCuZn High Entropy Alloys (HEAs). The mechanical alloying technique is employed to produce a high entropy alloy consisting of Fe, Co, Ni, Cu, and Zn in their raw form. Subsequently, the raw alloy powder is enriched with separate amounts of Y2O3, Er2O3, Pr2O3, and Sm2O3. The microstructural analysis of the samples obtained from the mechanical alloying process was performed utilizing the X-ray diffraction (XRD) technique. In addition, scanning electron microscopy (SEM) was employed to analyze the ODS-HEA samples encoded S1, S2, S3, S4, and S5. To investigate the transmission properties of gamma-ray and neutron radiation, experimental studies are carried out using two types of detectors: Ultra High Purity Germanium (HPGe) detector and Canberra NP-100B BF3 gas proportional detector, respectively. The X-ray diffraction (XRD) spectra of samples did not display any observable peaks that could be attributed to the presence of dispersed rare earth element (REE) oxides. The uniform distribution of the metallic constituents that make up the High Entropy Alloy (HEA) is observed in the samples. Additionally, it can be observed that the implementation of the ODS-HEA technique, incorporating a 3% (wt.) Er2O3 additive, results in the most advantageous results with respect to the characteristics of gamma ray absorption. The S3 sample demonstrated the greatest degree of neutron absorption, as demonstrated by a recorded value of 0.857 μSv/h, where the S1 sample demonstrated the minimum level of absorption, as evidenced by a recorded value of 0.452 μSv/h. Based on the observed effects on neutron and gamma-ray attenuation behaviors in ODS-HEAs, it can be concluded that Er2O3 exhibits characteristics of a monotonic oxide. This feature is particularly advantageous for applications that necessitate a dual enhancement in these behaviors. It can also be concluded that the S1 sample may be deemed appropriate for situations where the utmost consistency of chain reactions in nuclear reactor fuel rods is desired, due to its possession of the lowest neutron absorption properties.

Mechanical treatment of aluminum plate surfaces for improvements of capacitance and dielectric permittivity

The surface mechanical alloying (SMA) technique achieved high capacitances, improved capacitance (C) and dielectric permittivity (ε′) of mixed Aluminum/fiber-glass ‘Al/F-glass’ formed on aluminum plates. The radiofrequency RF range 0.1–106 Hz was applied on the Al/F-glass on Al plates, acting as parallel electrodes sandwiching the mixed ceramic Al/F-glass as dielectric. Capacitance increase observed after surface alloying on treated Al with small 1.5 balls than 6 mm balls on Al-plate & 1 A l-plate 2 respectively, giving twice the permittivity constant of the annealed Al. Deformation micro-scale cavities in Al surfaces played important role in raising capacitance and permittivity values; Interpreted as condensers inside a condenser caused capacitance increase according Maxwell-Wagner-Sillars effect. Dielectric relaxation model Havriliak-Negami Model was used to examine the occurrence of the Maxwell-Wagner-Sillars effect in alloyed Al/F-glass surfaces on Al plates, which confirms micro-cavities important role due to pre-treatment of Al surfaces.

Effects of silicon concentration on the magnetic and structural properties of nanostructured Fe-Si alloy synthesized by ball mill process

This study aims to elaborate on the production of a nanostructured Fe-Si alloy with varying silicon concentrations and how it can enhance the magnetic properties of the alloy. In order to achieve this, the mechanical alloying technique was employed to create the nanostructured alloy. After the mechanical ball milling process, the morphological, structural, and magnetic properties of the alloy were thoroughly analyzed using advanced techniques such as scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), and vibrating sample magnetometer (VSM). The results from these techniques revealed significant changes in the properties of the alloy. One of the major findings of this study was the appearance of Fe3Si phase, commonly known as Suessite, after the mechanical milling process. This indicates that the milling process caused a transformation in the crystal structure of the alloy. Additionally, an increase in silicon concentration led to a reduction in crystallite sizes, which was observed through the XRD analysis. Furthermore, the lattice strain and lattice parameters of the alloy were observed to increase with increasing silicon concentration until it reached 3%. After this point, the value of the lattice parameter remained constant, indicating that further increases in silicon concentration did not significantly impact the lattice structure of the alloy. The FTIR analysis revealed the presence of a distinct band at 1070 cm−1, indicating the occurrence of stretching vibrations associated with Fe-Si bonds. The milled samples exhibit improved magnetic properties, with increased saturation magnetization values observed as the silicon concentration increased.

Two Fe-Zr-B-Cu Nanocrystalline Magnetic Alloys Produced by Mechanical Alloying Technique

Fe-rich soft magnetic alloys are candidates for applications as magnetic sensors and actuators. Spring magnets can be obtained when these alloys are added to hard magnetic compounds. In this work, two nanocrystalline Fe-Zr-B-Cu alloys are produced by mechanical alloying, MA. The increase in boron content favours the reduction of the crystalline size. Thermal analysis (by differential scanning calorimetry) shows that, in the temperature range compressed between 450 and 650 K, wide exothermic processes take place, which are associated with the relaxation of the tensions of the alloys produced by MA. At high temperatures, a main crystallisation peak is found. A Kissinger and an isoconversional method were used to determine the apparent activation of the exothermic processes. The values are compared with those found in the scientific literature. Likewise, adapted thermogravimetry allowed for the determination of the Curie temperature. The functional response has been analysed by hysteresis loop cycles. According to the composition, the decrease of the Fe/B ratio diminishes the soft magnetic behaviour.

Nickel Slag/Laterite Soil and Nickel Slag/Iron Sand Nanocomposites: Structural, Optical, and Electromagnetic Absorption Properties.

Efforts to produce microwave absorber materials that are inexpensive and environmentally friendly have become a means of greening the environment. The breakthrough can be focused on industrial waste and natural materials for functional purposes and how to enhance their performance. We successfully synthesized nickel slag/laterite soil (NS/LS) and nickel slag/iron sand (NS/IS) nanocomposites using a simple mechanical alloying technique, and the electromagnetic (EM) wave absorption capacities of the nanocomposites were measured using a vector network analyzer. The structural properties of the nanocomposites were analyzed by X-ray diffraction spectroscopy, where the results of the analysis showed that NS/IS has the largest crystallite size (15.69 nm) and the highest EM wave absorption performance. The optical properties of the nanocomposites were determined from their Fourier transform infrared spectra using the Kramers-Kronig relation. As determined through a quantitative analysis of the optical properties, the distance between the longitudinal and transversal optical phonon wavenumber positions (Δ(LO - TO) = 65 cm-1) is inversely proportional to the reflection loss. The surface morphologies of the nanocomposites were analyzed by scanning electron microscopy, and the particle diameters were observed by binary image and Gaussian distribution analyses. The nanocomposite surface exhibits a graded-like morphology, which indicates multiple reflections of the EM radiation, consequently reducing the EM interference. The best nanocomposite for an attenuated EM wave achieved a reflection loss of -39.14 dB at 5-8 GHz. A low penetration depth has implications for the electrical charge tuning of the storage and composite magnets. Finally, the EM absorption properties of NS/IS and NS/LS indicate a 2-mm-thick environmentally friendly nanocomposite for EM absorption.

Analytical study to effects on reflection coefficient of Ti–Mn alloys at increasing concentration Mn element in the dental implants application

Manganese (Mn) is one of the trace elements in the human body, The titanium-manganese (TiMn) alloys have been used in some applications as well. The TiMn alloys with various manganese contents ranging from 2 to 12 wt % were prepared by using mechanical alloying and spark plasma sintering (SPS) techniques (Sibum, 2003). This paper investigated the effects of increasing manganese content in the Ti. Concentrations of Mn (2 wt % to 12 wt %) in titanium influence the reflection coefficients and acoustic signatures of Ti–Mn alloys by Scanning Acoustic Microscopy (SAM) technique, was determined by The oscillatory behavior, The spectral treatment of these signatures, via fast Fourier transform. Correspond to longitudinal and Rayleigh relations depend on Mn Concentrations, was Concluded that Mn Concentrations (from 2 wt % To 12 wt %) increase with increasing Bulk physical properties and Acoustic wave velocities (AWV) as Young's Modulus, Shear Modulus, Bulk modulus, Longitudinal Velocity, Transverse Velocity, and Rayleigh Velocity were (from 105 To 122)Gpa, (from 39.6 To 45.9)Gpa, (from 103 To 119.6)Gpa, (from 4862 To 6183) ms1, (from 2450 To 3115)ms−1and (from 1658 To 2064)ms−1 respectively.

Ball Milling and Consolidation Process of Al-Cr Powder Mixture—Microstructural Characterization

The interest in studying the synthesis of an Al–Cr alloy system by non-equilibria processes is due to the formation of metastable or quasicrystalline phases when rapid solidification has been utilized. Similarly, the formation of quasicrystals has been reported to a much lesser extent when the mechanical alloying technique was applied. In the present research, a mixture of powders of Cr and Al (both elements with a purity of 99.99%) with compositions of Al-5 and 7.5 at. % Cr was subjected to a ball milling process. Afterwards, the powder mixture was subjected to a consolidation process, conducted by pressing and sintering processes. The X-ray diffraction analyses revealed that during 20 h of milling there was no formation of metastable or quasicrystalline second phases detected. In addition, the X-ray diffraction peaks revealed that as milling time increased, the nanometric grain size decreased, and once the sintering treatment was applied, the crystallite size decreased following the same tendency. The dislocation density was estimated using the size of nanometric grains; this computation revealed that the dislocation density grew throughout the ball milling process; even after sintering, the multiplication of dislocations prevailed following the same tendency.

Production and characterization of GNPs-reinforced Al-based composite material by mechanical alloying

PurposeThe purpose of this study is to investigate the effects of graphene nanoplates (GNPs), and alloying time on aluminum matrix composite. After mixing the powdered materials in the alloying device, solid samples were formed by sintering. It is thought that the effect of using such a mechanical mixer on GNPs will be investigated and this study will give a perspective on the composites that GNPs will make with Al and its alloys.Design/methodology/approachMechanical alloying (MA) device capable of high-speed shaking (Spex) movement was used and alloying was performed by adding other metal powders into aluminum, which is the matrix material, with the addition of GNPs at three different rates and times. The crystal size and lattice stress parameters were calculated by obtaining the X-ray diffraction (XRD) graphics of the obtained powder mixtures.FindingsThe XRD graphs of the obtained powder mixtures showed that the Al peaks decreased when the MA time increased. When the scanning electron microscopy images of the powder mixtures were examined, it was observed that agglomeration occurred especially in 1 and 1.5 Wt.% graphene reinforced mixtures that were MA for 90 min. The increase in the amount of graphene had a negative effect on the homogeneous distribution. When the Vickers microhardness values of the samples were examined, the hardness value of all samples increased up to the MA time of 45 min, and decreased in the times over 45 min.Originality/valueThe use of GNPs in the mechanical alloying technique and the fact that this technique was performed on the Retsch MM 400 device, which is a Spex type mixer, shows the originality of the study in terms of time and material content.

Effet of hematite (Fe2O3) from natural iron ore as a catalyst in MgH2 as hydrogen storage materials

The main obstacle that hinders the application of fuel cell fuels for vehicles today is the hydrogen storage tube. Therefore, this paper will report the results of a study on MgH2-based hydrogen storage materials with Fe2O3 catalyst inserted (5 wt%, 10 wt%, 15wt%) and prepared by mechanical alloying technique for 10 hours. Fe2O3 samples were obtained from the Lhoong Setia Mining site in Jantang Village, Lhoong, Aceh Besar. The initial sample separation process was carried out manually using a bar magnet. Furthermore, hematite extraction was carried out with the addition of 1M HCL and NaOH each. Then the milling process of MgH2-Fe2O3 samples was carried out using a planetary ball mill. The results of the X-ray diffraction test showed that the MgH2 phase was the most dominant/mainstream phase. Thermal testing with DSC showed that the H2 desorption process experienced a decrease in temperature from 194.56 °C with a milling time variation of 7 hours.

Magnetic and Structural Properties of Fe-Ni and Fe-Ni-Gr Based Nanostructured Alloys Synthesized by Mechanical Alloying

Nanostructured FeNi and FeNiGr alloys were successfully synthesized by the mechanical alloying technique. The alloys formation and different magnetic properties were studied as a function of milling time in the range of 0 to 30h by X-ray diffraction (XRD) technique, Scanning Electron Microscope (SEM) analysis and a Vibrating Sample Magnetometer (VSM) process. The X-ray diffraction study confirmed the apparition of the α-FeNi alloy after 5h of milling with an average crystallite size of 26.80nm. The crystallite size obtained after 30h of milling is 10.13nm, While, the lattice deformation increases from 0.431 to 0.935%. in addition, the analysis of the magnetization curves of the Fe-Ni alloys revealed original magnetic properties: super paramagnetic behavior, and especially saturation magnetization and significant coercivity. ​​​​​​​ Furthermore, the addition of graphene into FeNi alloy, reduced its crystallite size from 11.56 to 6.65 nm, and increases the lattice strain and lattice parameter from 0.631 to 0.748% and from 0.28686 to 0.28704nm, respectively. Which, enhanced these magnetic properties, by increasing its coercivity (Hc) from 16. 07 to 135.42 Oe and Mr from 1.73 to 5.87 emu/g, while the magnetization saturation is decreased from 153.25 to 123.06 emu/g.

Comparison on structural andmagnetic properties of FeCoNi medium entropy alloy, FeCoNiAl and FeCoNiAlTi high entropy alloys

In the present study, we investigated the effect of configurational entropy on the phase evolution and magnetic properties of medium and high-entropy alloys. Three different, FeCoNi medium entropy alloys (MEA), FeCoNiAl, and FeCoNiAlTi high entropy alloys (HEAs) were synthesized through the mechanical alloying technique (MA). XRD analysis revealed the formation of the single fcc phase structure for FeCoNi MEA. The mixture of bcc and fcc phase is formed forFeCoNiAl HEA. However, for FeCoNiAlTi HEA the mixture of fcc, and bcc phases, along with a minor fraction of intermetallic R-phase is confirmed through the fitting of XRD data. The magnetic properties of FeCoNi MEA changed drastically by adding Al and Al, Tiwith Fe, Co, Ni as alloying elements for the formation of HEAs. The values of saturation magnetization (Ms) and coercivity (Hc) for FeCoNi MEA are 133.7 emu/g and 26.1 Oe, respectively. For FeCoNiAl HEA, the value of Ms decreased to 85.4 emu/g, and Hc increased to 74.2 Oe. However, for FeCoNiAlTiHEA, the value of Ms is reduced to 52.50 emu/g, and Hc increased to 90.55Oe. The present study clearly shows that the addition of different alloying elements significantly impacts the phase formation and the magnetic behavior of the MEA and HEAs.

Effects of Multi Walled Carbon Nanotube and Silicon Carbide Reinforcement on Wear Performance in Zinc-Aluminium Alloys

In this study, hybrid composite materials were produced by adding SiC (Silicon carbide) and MWCNT (Multi-walled carbon nanotube) to Zinc-Aluminium (ZA40) alloy, sintering under 700 MPa pressure and 500 °C using mechanical alloying and hot press technique. Hybrid samples were produced with 2% MWCNT constant and SiC ratio 1-2-3 and 4% by weight in the mixtures. The mechanical properties such as hardness and porosity of the produced hybrid composite materials were determined and their wear properties were investigated by traveling 300 m using 10 and 20N loads under 300 rpm constant speed in a ball-on-disc wear test setup. The obtained internal structure and wear surface images showed that the SiC and MWCNT reinforcement contributed significantly to the wear resistance of the hybrid composites, and in the SEM analyzes of the worn surfaces, there was a transition from abrasive wear to adhesive wear in the wear mechanism.

Study on the Influence of Cu Content on Phase Transition Characteristics of Fe75Ni(25-x)Cu x Elastocaloric Refrigeration Alloys

In this study, the mechanical alloying (AM) and powder metallurgy (PM) techniques were adopted to synthesize the Fe75 Ni(25-x) Cu x elastocaloric refrigeration alloys to research the effect of Cu contents on phase transition characteristics and microstructure of Fe75Ni(25-x) Cux elastocaloric refrigeration alloys. The conclusion was drawn that, with increasing Cu content, the phase transition characteristics changed and presented different changing trends. It was found that the phase enthalpy change value was 43.34J/g when the Cu content was 7at%, which was about 1.26 times of Fe15Ni (wt%) alloy. In addition, the FeNiCu alloy was a single-phase alloy with a crystal space group structure of Im-3m when the Cu content was 7at%, and the FeNiCu alloy was a two-phase alloy with crystal space group structures of Im-3m and Fm-3m when the Cu content was more than 7at%. This study provided an experimental basis for the theoretical investigation of the phase transition mechanism of FeNiCu elastocaloric refrigeration alloys.

Removal of Reactive Black 5 Azo Dye from Aqueous Solutions by a Combination of Reduction and Natural Adsorbents Processes

In this study, a combined process of reduction and adsorption for the degradation of azo dye with nanocrystalline Fe80Si10B10 powder as a reducing agent is analyzed. A mechanical alloying technique produced the powdered alloys needed for the redox process. The synthesized nanocrystalline structure favors the efficiency of the reduction step of Reactive Black 5 (RB5) azo dye. According to the UV-Vis analysis, the reductive process alone allowed for nearly complete color removal after 3 min of reaction. In this regard, the nanocrystallized FeSiB powder has excellent application potential in the first step of the reduction processes for degrading azo dye solutions. Indeed, the nanocrystalline FeSiB powder outperforms commercial Fe powders in terms of degradation efficiency because of the formation of multiple micro-batteries between the α-Fe solid solution and the Fe3Si nanocrystalline phases, favoring the loss of electrons from iron and exhibiting different corrosion resistance. In the second step, the adsorption process, the efficient removal of intermediate undesired compounds from the reduction processes, principally aromatic amines, is analyzed. Different adsorbents, including wood, graphene oxide, activated carbon, and pine particles, were used. The results suggest that graphene oxide and activate carbon performed the best for secondary product adsorption following RB5 degradation. The current study could serve as a guide for environmental applications, such as industrial wastewater treatment, using metallic powders produced by high-energy mechanical alloying.

Enhancement of electrical conductivity, optical band gap and ferromagnetic properties by co-doping of Co and Ti ions in canted antiferromagnetic hematite (α-Fe2O3) system

The Co and Ti ions have been co-doped at the sites of Fe3+ ions of α-Fe2O3 (hematite) structure by employing mechanical alloying technique and post heat treatment of the as-alloyed material under vacuum and air. The ratio of Co and Ti ions has been maintained at 50:50 in order to compensate charge disproportionate effect in the composition of α-Fe2-xTix/2Cox/2O3 (x = 0.2, 0.4, 0.6). The X-ray diffraction pattern and Raman spectra at room temperature have confirmed the formation of hematite (rhombohedral) structure as the major phase and a minor amount of TiO2 phase in some of the prepared samples. X-ray photoelectron spectra (XPS) have provided useful information of the chemical environment and electronic charge state of the metal (Co, Ti, Fe) ions in the lattice structure. The XPS spectra confirmed tetra-valence charge state of Ti ions, whereas a mixed valence charge state of Fe3+(Co2+) and Fe(2+δ)+(Co(3−δ)+) has been indicated for the Fe and Co ions. The mixed valence charge states indicated the enhancement of covalent character of the metal-oxygen bonds. In this work, details of the lattice structure, chemical composition, charge state of ions, optical, electrical and magnetic properties have been presented.

Phase Formation of Iron-Based Superconductors during Mechanical Alloying.

We successfully synthesized bulk Ba0.6Na0.4Fe2As2 and Sr0.5Na0.5Fe2As2 compounds by high-energy mechanical alloying (MA) technique. The MA process results in homogeneous amorphous phases of BaFe2As2 and SrFe2As2. It was found that the optimum time for high-energy milling in all cases is about 1.5-2 h, and the maximum amount of amorphous phase could be obtained when energy of 50-100 MJ/kg was absorbed by the powder. After a short-term heat treatment, we obtained nearly optimum sodium-doped Ba1-xNaxFe2As2 and Sr1-xNaxFe2As2 superconducting bulk samples. Therefore, MA is a potential scalable method to produce bulk superconducting material for industrial needs.

Microstructure and Elastic Properties of Hydroxyapatite/Alumina Nanocomposites Prepared by Mechanical Alloying Technique for Biomedical Applications

Although hydroxyapatite (HA) has exceptional biological qualities that inspire researchers to employ it as an appealing biomaterial for various purposes, its usage in hard tissue replacement applications is severely restricted because of its fragility. In order to create nanocomposites with the necessary mechanical properties for biomedical applications, HA was produced, and various amounts of alumina (Al2O3) were added to it. Additionally, the phase composition of the powdered nanocomposites was examined using the X-ray diffraction (XRD) technique. Crystal sizes, lattice strain, and dislocation density were all estimated as well. In order to measure the produced nanocomposite powders’ physical and elastic characteristics using the Archimedes method and ultrasonic non-destructive technique, they were then pressed and sintered at 1000 °C. The resulting information made it clear that further increases in the weight percentages of Al2O3 resulted in a 10.25, 25.64, and 33.33% reduction in crystal size. As a result of adding more Al2O3-up to 20 weight, percent-the results also showed that this properties-microhardness, compressive strength, Young’s modulus, elastic modulus, bulk modulus, shear modulus, and Poisson’s ratio-were improved by 109, 36.29, 95.5, 100.59, 104.97, 92.84 and 9.5%, respectively. Unfortunately, it increased its porosity by considerable amounts. It might be argued that the generated nanocomposites are favorable for biomedical applications.

Ni-Mn-Al Heusler Alloy Samples Preparation by Mechanical Alloying Method and Study of their Investigated Properties

Objective: In this work, ternary Ni-Mn-Al Heusler alloy powder samples were fabricated using mechanical alloying technique to study its alloy formation mechanism and the effects of mechanical alloying on the investigated properties. Methods: The samples were prepared using high energy planetary ball mill under argon conditions. The milling time of 0 h (hour/hours), 5 h, 10 h and 15 h were selected to see the progress of alloy formation. The microstructural, compositional, thermal and magnetic studies of ball milled powder samples were conducted. Findings: Compositional study reveals stoichiometric Heusler composition (X2YZ) of Ni-Mn-Al alloy with no contamination. The optimum milling time required for the formation of alloy by mechanical alloying resulted through the proper selection of milling parameters. The average crystallite size obtained reveals that nanocrystalline structure of Ni-Mn-Al alloy was achieved during the ball milling operation. The successive heating of powder particles in differential scanning calorimetry showed crystallization and alloy formation. Novelty/Applications: The magnetic study indicated soft ferromagnetic nature of the selected ball milled powder sample suggesting the alloy can be developed for possible ferromagnetic shape memory alloy applications. Keywords: Ni-Mn-Al; Heusler alloy; Mechanical alloying; Ball milling; Structural properties