High-energy Ball Milling Process Research Articles

Effect of ball milling on densification and alloying in SiCp/Al powder metallurgy processes

In this study, unprocessed raw Al, Cu, Mg powders, and SiC particles were mixed and subjected to high-energy ball milling (HEBM) to mitigate the negative effects of the oxide film on the quality of the pressureless sintering billets. Comparative experiments including pores and intermetallics examination were performed on both the mixed and HEBM powders across various preparation stages, including cold isostatic pressing, sintering, and hot extrusion of the 15vol.%SiC/Al-Cu-Mg. The pore structure and degree of alloying were analyzed using X-ray synchrotron radiation tomography. The results indicate that the brief HEBM process led to excellent mechanical properties in aluminum matrix composites after pressureless sintering and hot extrusion. The composites using ball-milled powder was relatively denser and complete alloying after sintering and extrusion, resulting in a density of up to 0.995 and a uniform distribution of Cu elements. The HEBM SiCp/Al had a tensile strength of 573 MPa and a fracture strain of 5.1 % which were higher than that of the mixed SiCp/Al. The results indicate that diffusion of alloy elements such as Cu was hindered by the interfaces between powders, led to Cu segregation and lower density of only 0.982 even after extrusion. Therefore, the composites using mixed powder had a lower tensile strength of 483 MPa and a fracture strain of 3.5 %. The study concluded that reducing the number and types of inter-particle interfaces could enhance the alloying and pore bridging processes.

Microstructure and Corrosion Resistance of 7075 Aluminium Alloy Composite Material Obtained from Chips in the High-Energy Ball Milling Process.

The high-energy ball milling process was applied to fabricate a composite material from 7075 aluminium alloy milling chips, silicon carbide, and titanium dioxide powders. Raw materials were ground, and the obtained powders were cold pressed and sintered. It was demonstrated that this method can be used in the recycling of aluminium alloy scrap characterised by a high surface-to-volume ratio, and also that chemical removal of the oxide layer from chips is not necessary. The finest particles, with 50 vol.% of their population below 36 μm, were obtained after grinding for 60 min at a 1000 rpm rotational speed. Such an intensive grinding was necessary to fabricate the compact composite material with a homogeneous microstructure and a low porosity of 0.7%. The corrosion resistance of the composites was studied in 3.5 wt.% NaCl solution using cyclic voltammetry and electrochemical impedance spectroscopy, and corrosion rates in the range of ca. 342 and 3 μA∙cm-2 were obtained. The corrosion mechanism includes aluminium alloy dissolution at the matrix/reinforcement interphase and around intermetallic particles localised within the matrix grains.

A novel coarse-grained modeling and simulation for microstructure and shear evolution of induced dipole dominant electrorheological fluid

Induced dipole dominant electrorheological fluid (ID-ERF) is a new type of ERF. After high energy ball milling (HEBM) process, dielectric particles produce a large number of oxygen vacancies, and the dipoles formed by the polarization of these oxygen vacancies provide excellent ER properties. ID-ERF has the advantages of high shear stress, low current density, long service life, anti-sedimentation, simple preparation method, etc. It should be a new generation of ERF material suitable for practical application. In this work, facing at the shortcomings of traditional particle MD simulation of ERF system, a coarse-grained molecular dynamics (CGMD) model is constructed. The evolution of ID-ERF is simulated under the conditions of no electric field and 5 kV/mm electric field. Proves that there is an adsorption layer of carrier liquid on the surface of ER particles, and shows BCT lattice arrangement under electric field. The sinusoidal shear strain is applied to the model, and calculate the variation of strain amplitude, loss factor, storage modulus and loss modulus. In addition, we prepared ID-ERF and tested its performance to compare with the simulation results.

A novel sustainable AZ31 based Mg matrix composite reinforced with recycled IN718 powder for circular materials economy

The pursuit of sustainable practices in manufacturing has sparked an increased interest in recycling and reusing materials to reduce waste and environmental effect. One interesting technique is incorporating recycled materials to develop advanced composite materials. In this study, we focus on utilizing recycled Inconel IN718 powders as reinforcement particles in AZ31D. Powders of IN718 finer than 37 μm, developed from machining chips through high energy ball milling process, are infused into AZ31 through friction stir processing (FSP), enabling a circular economy practice in advanced material development. The resulting composite material is evaluated for its microstructure and mechanical performance. Microstructural study reveals a uniform distribution of reinforcement particle inside the matrix throughout the processed zone. Strong interfacial bonding between the matrix and reinforcement, and the addition of dispersion strengthening mechanisms helped reducing the tension/compression yield asymmetry problem. The study highlights the use of recycled materials in composites to achieve sustainability in manufacturing.

Few-layered graphene/Al-Cu alloy matrix composites: Mechanical, tribological and corrosion properties

Nano-sized graphene incorporated Al-5.5 wt% Cu alloy matrix composites were produced via powder metallurgy. Nano-sized graphene powders obtained via the arc-discharge method were incorporated into Al and Cu powders in varying amounts (0–5 wt%) by applying a high-energy ball milling (HEBM) process for different durations. The consolidated composites were prepared by the succeeding uni-axial pre-compaction and pressureless sintering stages. The as-blended and mechanically alloyed (MAed) powders and bulk composites were comparatively characterized in terms of their physical, thermal, microstructural, tribological, mechanical, and corrosion properties depending on the graphene amount and the duration of mechanical alloying (MA). After 4 h of MA, the starting as-blended powders presented as coarse and discrete particles gained a refined and homogenized microstructure with more equiaxed dimensions. Bulk FLG/Al-5.5Cu (FLG in amounts of 0, 0.5, 1, 2, and 5 wt%) composites are ever-increasing hardness values with rising graphene as 109, 101, 128, 238, and 263 HV, respectively. The compressive strength improved gradually to 495 MPa using graphene up to 1 wt%, though contrary to the high hardness values, a drastic decline was observed by 5 wt% graphene incorporation. Besides, the wear resistance of composites outperformed that of the Al-5.5Cu matrix by incorporating this amount of reinforcement together without a deterioration in the corrosion resistance.

Characterization of the Ge@GeO2-C Composite Anode Synthesized Using a Simple High-Energy Ball-Milling Process for Li-Ion Batteries

Characterization of the Ge@GeO2-C Composite Anode Synthesized Using a Simple High-Energy Ball-Milling Process for Li-Ion Batteries

Synthesis of NiCrAlY nano-scale powder by high-energy ball milling process for thermal spray coating application

These days, during the issues of climate change, there has been a shift in the energy industry from using fossil fuels to more environmentally friendly fuels such as biomass fuels. Biomass fuel is considered CO2 neutral because the carbon produced during combustion in the form of CO2 emissions can be used for new plant growth. However, besides the advantages of using biomass fuel, a problem arises when biomass fuel contains a high concentration of corrosive agents, which can be released along with hot fuel gas. These corrosive agents can damage the boiler components. Coating technology is one of the solutions to protect components that work at high temperatures against the corrosion threat. One type of coating that can be used in high-temperature applications is NiCrAlY coating by the high-velocity oxide (HVOF) process. One interesting topic that people are developing is using nano-scale coating to increase the coating’s resistance against hot corrosion and cracking. Nano-scale powder feedstock is needed to produce nano-scale coating material. In this research, top-down method is used to synthesis nano-scale powder. One of top down method, the high-energy ball milling processs, is a promising method to synthesize nano-scale powder material. Therefore, in this research, the ball milling process is used to prepare nano-scale product. The results showed that this method was successful to make the nano-scale powder. The nano-scale powder was characterized by several methods to investigate the morphology and properties of the powders. However, there are still many challenges in producing nano-scale powder that meets HVOF feedstock powder requirements. In the long run, it is expected that this research can answer those challenges so that at the end, the good quality of nano-scale powder can be achieved

Fe-doped ZnO nanoparticles prepared by high energy ball milling with enhanced sonophotocatalytic performance

Zinc oxidenanostructures were synthesized using a thermal decomposition method and subsequently doped with Fe (III)in this study. Techniques such as X-ray diffraction, Field emission scanning electron microscopy, and Fourier transform infrared spectroscopy were used to investigate the structural and chemical composition of nanomaterials. Fe-doped ZnO was synthesized using a simple, low-cost planetary high-energy ball milling process. The sonophotocatalytic activity of Fe-doped ZnO under visible light and ultrasonic waves was then studied. Another aspect of this study is the utilization of visible light, which is far more accessible and cost-effective than UV light. Malachite green (MG) and phenol were applied as water-soluble contaminants. MG degraded about 87.65% after 1 h in the presence of a Fe-doped ZnO catalyst under visible light and ultrasonic waves simultaneously. Phenolwas degraded by approximately 64.50% under the same conditions.

Bosentan monohydrate and sildenafil base as two companions in enabling formulations

Hypothesis: Sildenafil base and bosentan monohydrate are co-administered in a chronic therapy of pulmonary arterial hypertension (PAH). Both drugs are poorly soluble in water, and their bioavailability is limited to ca. 50 %. Since bosentan is a weak acid, whereas sildenafil is a weak base, we assumed that their co-amorphization could: (i) improve their solubility in the gastrointestinal fluids, (ii) enable to reach supersaturation and (iii) ensure stabilization of supersaturated solutions. If successful, this could accelerate the development of new fixed-dose combination drugs. Experiments: The co-amorphous formulations were prepared using high energy ball milling. Their solid state properties were assessed using XRD, DSC, FT-MIR, and dielectric spectroscopy. Particle size distribution and surface wetting were also analyzed. Polarizing optical microscopy and scanning electron microscopy were applied to assess the microstructure of these powders. A new HPLC-DAD method was developed for a simultaneous quantification of both drugs. Findings: It was shown that binary formulations in which bosentan was molecularly dispersed in sildenafil base (Tg = 64-78 °C) could be manufactured in the high energy ball milling process. When the sildenafil load was below 50 wt. %, the formulations showed the greatest thermal stability and formed long-lasting bosentan supersaturation in PBS.

Unlocking the Power of Magnesium Batteries: Synergistic Effect of InSb-C Composites to Achieve Superior Electrochemical Performance.

Pure magnesium anode used in rechargeable magnesium batteries (RMB) exhibits high theoretical capacity but has been challenged by the passivation issue with conventional electrolytes. Alloy-type anodes have the potential to surpass this issue and have attracted increasing attention. However, the kinetic performance and stabilities of conventional alloy anodes are still constrained. In this study, the InSb-10%C anode is synthesized by a two-step high-energy ball milling process. The InSb-10%C anode exhibits a remarkably high capacity of up to 448 mA h g-1, significantly improved cycle performance (234 mA h g-1 at 100 cycles) and rate performance (168 mA h g-1 at 500 mA g-1). The above-mentioned superior performance of the InSb-10%C anode for RMBs is attributed to the cellular graphitized amorphous carbon composite structure (CGA) which effectively refines the particle size and restricts the volume expansion. Additionally, the reduced surface electron density of InSb combined with the high conductivity resulting from graphitization enhances the Mg2+ diffusion performance. Notably, the InSb-10%C anode demonstrates good compatibility with conventional halogen-free salt ether-based electrolytes in the full battery configuration.

A novel nanocomposite-based zeolite for efficient remediation of Cd-contaminated industrial wastewater

Novel nanocomposite sorbent was produced by depositing nanostructured water treatment residual (nWTR) onto zeolite (Ze) using high-energy ball milling process. The physicochemical properties of nanocomposite (Ze-nWTR) prior and after Cd adsorption were analyzed by SEM–EDX, FTIR, BET and XRD. A batch study of cadmium adsorption (Ze-nWTR) was performed at various process parameters (sorbent dose, contact time, solution pH, competing ions, initial concentration and temperature). The obtained data were fitted to various equilibrium and kinetics models. The Langmuir and power function models successfully described Cd adsorption equilibrium and kinetic processes, respectively. The maximum adsorption capacity (qmax) value of Cd by Ze-nWTR nanocomposite (147 mgg−1) was 3 and 5.9 times higher than those of nWTR and zeolite sorbents, respectively. Increasing temperature from 287 to 307 K has resulted in increasing the maximum Cd adsorption capacity (qmax) of the nanocomposite from 147.9 to 270 mgg−1. The calculated thermodynamics parameters suggested physical and chemical attraction between Cd and Ze-nWTR and the association of dissociative mechanism in Cd(II) sorption process. The excellent reusability and Cd removal ability of Ze-nWTR nanocomposite (98%) from industrial wastewater confirm its potential as promising adsorbent for wastewater treatment applications.

Rare-Earth Ion Loss of Er- or Yb-Doped LiNbO3 Crystals Due to Mechanical Destructive Effect of High-Energy Ball Milling

Structural changes of Er- or Yb-ion doped LiNbO3 (LN) nanocrystals were studied in relation to the high-energy ball milling process. The evolution of the size of the particles and the formation of different phases were followed by dynamic light scattering and X-ray diffraction measurements, while the electronic transitions of rare-earth (RE) ions were investigated by absorption spectroscopy in the infrared spectral range. During the milling process, RE ions left the crystal lattice and an RE2O3 phase appeared to an increasing extent next to the LN. The change in the absorption spectra and the phases formed during the grinding process were found to be very similar for both investigated RE ions and were independent of their original concentration in the starting crystal samples. The extent of the RE loss was found to be 90% after 100 min of wet grinding.

Tungsten heavy alloy: Nano-crystallinity and alloying induced low temperature sintering, microstructure and mechanical properties

In this study, a tungsten heavy alloy with a composition of 90 W-4.9Ni-2.1Fe-3.0Cu was processed using powder metallurgy. Pure elements were ball-milled to develop a mechanically alloyed nano-grained solid solution to reduce the required sintering temperature. The alloy was then liquid-phase sintered in a hydrogenated argon atmosphere at 1250 °C. Microstructural characterization revealed that the high-energy ball milling process successfully developed a tungsten solid solution with a reduced tungsten grain size to a level of 15 nm, facilitating effective low-temperature (i.e., 1250 °C) liquid-phase sintering with 88% relative density. The tungsten grains grew mostly in a polygonal shape, coalesced to a large size, and had strong interfacial integrity with the nickel‑iron‑copper matrix. Mechanical properties characterization revealed a significantly high microhardness level of 380 HV, compressive yield strength of 910 MPa, and ultimate compressive strength of 1326 MPa. The applied compressive stress induced intergranular crack propagation leading to the fracture of the sample with a failure strain of 25.6%.

Enhanced lithium dendrite suppression ability through SiO2 substitution in superionic halogen-rich argyrodites and their application in all-solid-state lithium batteries

Among the inorganic solid electrolytes, it has been reported that argyrodites of sulfide-based electrolyte systems have a number of advantages, including high ionic conductivity and mechanical flexibility. Despite these advantages, their poor compatibility with Li metal still represents a problem. In this work, we prepared a halogen-rich argyrodites Li6-xPS5-xCl1+x solid electrolyte using a high-energy ball milling process. According to the composition test, Li5.3PS4.3Cl1.7 exhibited a high ionic conductivity (9.0 mS cm−1) at room temperature. Thus, we proposed SiO2 doped halogen-rich argyrodites while aiming to achieve improved electrochemical performance and the ionic conductivity. At a value of 9.4 mS cm−1, the ionic conductivity of Li5.34P0.96Si0.04S4.22O0.08Cl1.7 compositions was slightly increased compared to that of Li5.3PS4.3Cl1.7 (9.0 mS cm−1). Moreover, that composition showed a higher critical current density (1.0 mA cm−2) than that of Li5.3PS4.3Cl1.7 (0.35 mA cm−2), indicating that SiO2 doped Li5.3PS4.3Cl1.7 solid electrolyte improved the compatibility of the electrolyte against Li metal by reducing the side reaction with the Li metals. The air stability was also enhanced after SiO2 doping. These results confirmed that metal oxide doping in halogen-rich argyrodites contributed to high ionic conductivity and good electrochemical performance.

Milled graphitic nanoparticle toughened epoxy composites via increased resistance to in-plane crack propagation

Fascinating features of 2D-based carbon materials like graphene have drawn increasing attention to fulfill the desire to enhance the fracture toughness of epoxy composites. However, challenges remain to improve their dispersibility in polymers and increase interaction ability. Thus, work is needed to synthesize alternative cost-effective 2D carbon nanofillers capable of delivering consistent performance as a reinforcer to monitor the fracture toughness of the epoxy composites. The present study demonstrates transforming graphite to ball-milled graphite (BMG) via an effective high-energy wet ball milling process. Herein a noteworthy size reduction is achieved for the BMG ranging from ∼217 to 227 nm. Microscopic investigation spotted an exfoliated 3D networked graphite nanosheet with nanopores. These BMGs were functionalized to attach amine-based silane moieties and were incorporated into the epoxy network. Consequently, even at higher loading levels, they showed their astonishing capability to enhance the crack far field resistance of nanocomposite resulting in significantly improved fracture toughness and energy to ∼2.31 MPa m1/2 and ∼11.30 kJ/m2, respectively. Improvement is ascribed to the better dispersing ability of BMG, which provides a consistent strong interfacial interaction with the epoxy network to modulate material resistance to fracture. Such environmentally friendly nanofillers must be industrially acceptable for synthesizing durable epoxy nanocomposite systems and can be utilized to prepare structural composites.

A Comparative Analysis of Hydrogen Storage Characteristics in AZ31 Magnesium Alloy with the Addition of Graphene and Carbon Nanotubes via Ball Milling Process

In the present investigation, an examination was conducted on the hydrogen storage performance of industrial waste grade AZ31 magnesium alloy when combined with either Carbon Nanotubes or Graphene. This study aims to understand the enhancement of hydrogen storage properties reinforced with polymer materials, such as Graphene or Carbon Nanotubes. The experimental samples, composed of AZ31 Magnesium Alloy combined with either Carbon Nanotubes or Graphene, were crafted through gravity casting. Thereafter, a high-energy ball milling process was employed to further refine the hydrogen storage material powders. The micrographic structures of all the sample powders were analyzed by x-ray diffraction (XRD), and scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS). Additionally, the average particle size distributions of the sample powders were quantified for comprehensive characterization. The absorbed and desorbed hydrogen capacity and kinetics was calculated by a Sievert's type apparatus. Overall, the performance of the sample powder AZ31-0.1G showed the highest absorption and desorption at a rate of 0.0036 wt%/s and 0.0084 wt%/s. Moreover, the hydrogen capacity of AZ31-0.1G reached the highest value at 5.32 wt%. The acquired data unveils that with the adding of either Graphene or Carbon Nanotubes as additives significantly improved the hydrogen storage capacity of AZ31 magnesium alloy.

Synthesis of Sb-doped Li10P3S12I solid electrolyte and their electrochemical performance in solid-state batteries

The glass-ceramic Li10P3S12I solid electrolyte exhibited moderate ionic conductivity of ∼3 mS cm−1, but it shows low interface stability with lithium, poor moisture stability, and the electrochemical performance is not well established with respect to lithium. In this work, we enhance the ionic conductivity, interface stability, and air stability using Sb-substitution in Li10P3S12I glass-ceramic solid electrolyte using a high-energy ball milling process followed by a low heat treatment process. The ionic conductivity analysis reveals that the prepared Li10.1P2.95Sb0.05S12I glass ceramic composition shows a higher ionic conductivity of 5.9 mS cm−1 at 25 °C than Li10.1P2.95Sb0.05S12I (5.06 mS cm−1). The Li10.1P2.95Sb0.05S12I glass ceramic symmetric cell exhibits a better critical current density of 1 mA cm−2 than bare (0.7 mA cm−2). Also, it demonstrates better DC cyclability at 0.25 mA cm−2 without internal short circuits after 80 cycles. The Sb-substitution not only enhanced the ionic conductivity, also increased the moisture stability according to HSAB theory. The lithium solid-state battery is constructed using the Li10.1P2.95Sb0.05S12I electrolyte that demonstrates a high discharge capacity of 146 mAh g−1 at 0.1C rate than bare electrolyte (126 mAh g−1).

Enhancing the Microhardness of Coatings Produced by Cold Gas Dynamic Spraying through Multi-Reinforcement with Aluminum Powders Containing Fullerenes and Aluminum Nitride

Coatings with high hardness were successfully obtained using low-pressure cold spray (LPCS) technology from nanocrystalline powders based on the aluminum alloy AlMg6, which were multi-reinforced with 0.3 wt.% fullerenes and 10–50 wt.% AlN. The powders were synthesized through a two-stage high-energy ball milling process, resulting in a complex mechanical mixture consisting of agglomerates and micro-sized ceramic particles of AlN. The agglomerates comprise particles of the nanocomposite material AlMg6/C60 with embedded and surface-located, micro-sized ceramic particles of AlN. Scanning electron microscopy and EDS analyses demonstrated a uniform distribution of reinforcing particles throughout the coating volume. An X-ray diffraction (XRD) analysis of the coatings revealed a change in the predominant orientation of matrix alloy grains to a more chaotic state during deformation over the course of cold gas dynamic spraying. A quantitative determination of AlN content in the coating was achieved through the processing of XRD data using the reference intensity ratio (RIR) method. It was found that the proportion of transferred ceramic particles from the multi-reinforced powder to the coating did not exceed ~65%. Experimental evidence indicated that LPCS processing of mono-reinforced nanocrystalline powder composite AlMg6/C60 practically did not lead to the formation of a coating on the substrate and was limited to a monolayer with a thickness of ~10 µm. The microhardness of the monolayer coating obtained from the deposition of AlMg6/C60 powder was 181 ± 12 HV. Additionally, the introduction of 10 to 50 wt.% AlN into the powder mixture contributed to the enhancement of growth efficiency and an increase in coating microhardness by ~1.4–1.7 times. The obtained results demonstrate that the utilization of agglomerated multi-reinforced powders for cold gas dynamic spraying can be an effective strategy for producing coatings and bulk materials based on aluminum and its alloys with high microhardness.

High ionic conducting NaSICON enabled by mechanical activation enhanced reaction

NaSICON-type materials have been investigated since 70s and become an attractive candidate for energy storage and many other emerging applications owing to their good ionic conductivity. However, further enhancement in ionic conductivity at room temperature (RT) and facile processing methods to synthesize NaSICON in an energy efficient and low cost manner are required to enable various emerging applications. This study reports a new processing method, termed as mechanical-activation-enhanced reactions, to address these challenges simultaneously. It is shown that Na3Zr2Si2PO12 membranes with little or no impurity, relative densities ∼95 %, and total ionic conductivity of 1.53 × 10−3 S/cm at RT can be synthesized through one high-energy ball milling process followed by one step of high-temperature reaction(s) and sintering at the same time, greatly simplifying the procedure for synthesizing NaSICON membranes while achieving the outstanding ionic conductivity reported in the literature. It is found that mechanical activation at RT has significantly increased the reactivity of the reactants, accelerated the reaction kinetics in forming NaSICON, and increased the bottleneck size of the NaSICON crystal for Na ion transport. This study has provided a new direction to synthesize high performance, low cost NaSICON membranes and offered guidelines for achieving NaSICON membranes with superior ionic conductivity in the future.

Modification of 316L steel powders with bronze using high energy ball milling for use as a binder component in PBF-LB/M printing of diamond-metal matrix composites

For the processing of diamond-metal matrix composites, the powder bed fusion using a laser for metals (PBF-LB/M), represents a new promising method for the additive manufacturing of diamond tools for concrete and rock machining, even with more complicated geometries. Previous research activities show a strong tendency for cracking and delamination during the construction process of the samples. This behavior is caused by thermal residual stresses associated with the embedded diamonds. To control these negative effects on the process side, the volume energy density is reduced accordingly, which, however, led to increased pore formation. This publication deals with an approach on the material side to modify a 316L stainless steel base powder with an addition of 20 wt% bronze via a high energy ball milling (HEBM) process in such a way that a homogeneous solid solution phase is created. A significantly increasing of the melting interval and a decreasing of both solidus and liquidus temperature was observed, which can reduce pore formation in the PBF-LB/M-process. In addition, XRD-diffractometry and SEM/EDS-analysis showed that the homogeneous solid solution phase of this alloyed powder segregates again into Fe- and Cu-rich phases when heated up to the melting point.