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Metal matrix nanocomposites reinforced with carbon nanotubes (CNTs) have attracted considerable attention due to their potential for enhanced mechanical and tribological performance [1-2]. In this study, Cu/CNTs and Cu–Fe/CNTs nanocomposites were fabricated via a powder metallurgy route integrating planetary ball milling, discrete element method (DEM) simulation, and spark plasma sintering (SPS). Elemental Cu, Fe, and CNT powders were homogenized using a planetary ball mill. The powder mixing and milling dynamics, including particle collisions, energy transfer, and CNT dispersion behavior, were systematically investigated through DEM simulation to optimize milling parameters and achieve uniform reinforcement distribution. The milled powders were subsequently consolidated by SPS, enabling rapid densification and strong interfacial bonding while minimizing CNT degradation. The phase composition and microstructural evolution of the sintered Cu/CNTs and Cu–Fe/CNTs nanocomposites were characterized, followed by an evaluation of their mechanical and tribological properties. Hardness and wear tests revealed that both nanocomposite systems exhibited significantly improved hardness and wear resistance compared to monolithic Cu, with the Cu–Fe/CNTs nanocomposites showing superior performance due to synergistic solid-solution strengthening and enhanced load transfer mechanisms. This work demonstrates that the combined experimental and DEM based simulation approach is an effective strategy for designing high-performance copper-based nanocomposites with tailored mechanical properties.
The grinding process can be easily described mathematically using two basic functions (selection and breakage). The selection function determines the interaction of ball-to-powder contact number of probability [1]. A breakage function is that predicts the particle size distribution that will be generated by the grinding force of a small particle of powder at the moment [2]. Therefore, this study aimed to investigate the characteristics of the grinding process by milling coarse sand powder using a high-energy ball mill. The ball-to-powder and pot wall-to-powder contact numbers, along with the particle size distributions, were evaluated for grinding kinetic analysis of two functions. Furthermore, these results were correlated with the ball impaction and shear energy obtained from DEM simulations to clarify the relationship between the mechanical energy input and the grinding behavior. The sand of particle size distribution of the sand powder was measured using a particle size analyzer (PSA) and its surface morphology was examined using a scanning electron microscopy (SEM). We calculated the grinding kinetics analysis using the Tanaka’s equation [3] with results of the particle size distribution of the powder under different experimental conditions. The selection function varied depending on the different ball diameters, and the rotation speed also had a strong effect.
Carbon Nanotube (CNT)-reinforced composite materials have garnered extensive attention in both scientific and industrial domains due to their outstanding physical, mechanical, thermal, and electrical properties. Copper (Cu) and CNT-based composites have been developed and characterized, although these composites are often described as having poor wear resistance and insufficient mechanical flexibility. To overcome these limitations, iron (Fe), which is inexpensive, widely available, and possesses favorable mechanical properties has been identified as an ideal metal matrix. This study aims to evaluate the potential of iron-based composites in addressing the shortcomings of copper-CNT alloys. Cu, Fe powder, and carbon nanotubes (CNTs) were processed using planetary ball milling (PBM) to fabricate nanocomposites. The results were systematically analyzed using SEM, XRD, and FESEM. Based on these analyses, the optimal conditions were selected to fabricate the composites via spark plasma sintering (SPS) at 700°C under a pressure of 40 MPa. The composites were subjected to microhardness and wear resistance testing, and the experimental results revealed that the incorporation of Fe into Cu–CNT composites markedly increased hardness and significantly enhanced wear resistance.
Mechanical milling has emerged as a versatile solid-state powder processing technique for the synthesis and modification of advanced materials. This method involves repeated cold welding, fracturing, and re-welding of powder particles in a high-energy ball mill, leading to significant refinement of microstructure and enhanced material properties. The process enables the production of nanostructured materials, metastable phases, solid solutions, and composite systems that are often difficult to achieve through conventional routes. In this study, the fundamental mechanisms of mechanical milling and their influence on particle size reduction, phase transformation, and defect generation are examined. Key process parameters such as milling time, rotational speed, ball-to-powder ratio, and milling atmosphere are discussed in relation to their impact on the structural and physicochemical properties of the processed powders. Emphasis is placed on the role of mechanical activation in enhancing reactivity and promoting solid-state reactions at relatively low temperatures. Furthermore, recent applications of mechanical milling in the preparation of magnetic materials, catalysts, ceramics, and metal matrix composites are reviewed, highlighting its potential in tailoring functional properties for industrial and environmental applications. Despite its advantages, challenges such as contamination, agglomeration, and scalability are also addressed. Overall, mechanical milling represents a powerful and flexible approach for solid-state powder processing, offering significant opportunities for the design and development of advanced materials with controlled structure and performance.
Contamination of the environment with heavy metals, particularly copper (Cu) presents significant risks to both ecosystems and human health. Due to its abundance in Mongolia, natural zeolite is a promising water purification material, offering economic and environmental advantages. This research explores the adsorption of Cu on both natural and composite zeolite materials through batch and column experiments. The adsorption capacities of the natural zeolite and the composite zeolite were estimated in both batch and column processes. Composite zeolite materials demonstrated superior adsorption efficiency due to their enhanced functional groups and increased surface area, as observed in batch experiments. Under initial conditions of 50 mg/l concentration, a flow rate of 10 ml/min, and a column volume of 2.35 cm³, the breakthrough was observed at a total solution volume of 8000 ml. Additionally, the breakthrough curve of the column adsorption experiments was estimated using the Thomas model. The adsorption capacity in the lead column was estimated 18 mg/g for natural zeolite, whereas the adsorption capacity was 17.99 mg/g for composite zeolite using the Thomas model. However, the mass of the composite zeolite is almost two times less than the natural zeolite. Compared to previous research, the production of composite zeolite materials is more cost-effective, while exhibiting improved adsorption capacity.
In 2023, a water quality study found that 86% of groundwater sources in Mongolia’s Gobi region failed to meet safety standards, mainly due to high water hardness and heavy metal contamination. While a lot of research has focused on removing heavy metals, much less attention has been given to reducing water hardness. This research explores natural clinoptilolite zeolite (1–2 mm) for water hardness reduced. Zeolite was activated using a planetary ball mill, with optimalconditions (150 rpm, 5 minutes, 3 mm balls). Under these conditions, batch adsorption showed effective Ca2+ and Mg2+ removal, with synthetic hardness water (28.5 mg-eq/L, 18 mg-eq/L) and the groundwater (11 mg-eq/L, 2.5 mg-eq/L) samples reaching regulatory standards in 780 minutes and 30 minutes. Batch adsorption experiments using synthetic hard water and both activated and natural zeolite reduction in total hardness by 50–70 %, with calcium ion removal by 70–86 % and magnesium ion by 26–39 %. Results demonstrate that natural zeolite is an effective, low-cost, and environmentally friendly material for softening hard water
To improve the properties of copper, a copper-based nanocomposite was fabricated using carbon nanotubes (CNTs), with copper powder produced by Steppe Powder LLC. Copper powders with two different raw particle sizes (70 µm and 110 µm) were selected, and various milling parameters, including milling time (1, 3, 6, and 12 hours), rotational speed (100, 300, and 500 rpm), and ball size (5 mm, 10 mm), were adjusted to compare the resulting composite materials. A scanning electron microscope (SEM) was used to analyze particle size and morphology, while a particle size analyzer (PSA) was employed to determine the particle size distribution. A field emission scanning electron microscope (FE-SEM) was used to examine the dispersion of CNTs on the copper particles. Additionally, the discrete element method was applied to study the milling mechanism in the ball milling machine. The results indicated that for a rotational speed of 300 rpm, increasing the milling time led to the flattening and growth of the composite particles, whereas at 500 rpm, longer milling times resulted in more flattened and significantly reduced particle sizes. Regarding CNT dispersion, at 300 rpm with a milling duration of 12 hours, CNTs were weakly attached to the copper surface. In contrast, at 500 rpm for 12 hours, CNTs were successfully embedded into the surface of the copper particles.
In this study, the influence of the contact number, the contacts of the ball-to-ball and ball-to-wall, shear energy, and impaction on the evolution of metal powder characteristics was studied with DEM simulation. The characteristics of metal powders were studied in a planetary ball mill under various experimental conditions, such as three different ball sizes, rotation speeds, and milling times, using a discrete element method (DEM) simulation. The particle morphology and size evolution of metal powders were determined using scanning electron microscopy (SEM) and particle size analyzer (PSA). To determine the contact number between the ball and the wall as well as the motion of the ball within the planetary ball mill, the shear end impact energy produced during the collision was examined using the DEM simulation. When compared under the same experimental conditions and energy, the morphologies of metal powder particles were radically different. The characteristics of raw metal powder were found to have an impact on the experimental results.
Natural zeolites are versatile minerals with a range of applications due to their unique properties, such as ion exchange, adsorption, and molecular sieving. Natural zeolites have been increasingly used in various application areas such as industry, environmental protection, medicine, and agriculture. Mongolian Gobi region groundwater has high hardness, heavy metal pollution, and high salinity. This research studied the possibility of purifying the hardness and heavy metal-polluted water of the Gobi region by mechanochemical activation of natural zeolite. We mainly explored the effect of experimental conditions, such as rotation speed, ball diameter, milling duration as well as ball to powder ratio and ball filling ratio, on the activation of natural zeolites. Natural zeolite activation by the mechanochemical method was determined with minimal energy consumption and optimal conditions at rotation speeds of 100, 150, and 200 rpm, milling times of 3, 5, and 10 minutes, and ball sizes of 1, 3, 5 mm using a planetary ball mill. When carrying out absorption at the optimal mechanochemical value, standard hardness water was calculated from the measurement values of Ca+2 and Mg+2 in plant A, and batch absorption was performed for 30-1440 minutes and the mass of absorbent material was 1, 5 , 10 g, the hardness decreased as the mass of the absorbent material and the time of absorption increased. The initial Ca+2 ion concentration was 580-600 ppm, after 780 minutes it reached the standard content of 100 ppm, and after 1440 minutes it became 75 ppm, which was included in the drinking water standard. We explored the potential of mechanochemical activation as a viable method for enhancing the utility of natural zeolites in groundwater purification applications, contributing to more sustainable water management practices.
The effect of variation of ball sizes on the grinding kinetics of calcite powder was studied and ball-to-ball and ball-to-wall collision of shear energy and ball impaction was calculated through a DEM simulation. Also, as the ball size decreases, the contact number increases and the effect on the powder increases, so we chose 0.3 mm and 3 mm zirconia balls in this study. The calcite powder particle morphology and size were characterized by scanning electron microscopy (SEM) and particle size analyzer (PSA). The grinding kinetics was calculated by Tanaka’s equation for ultrafine grinding based on particle size changes of calcite powder using a planetary ball mill. This study showed that grinding kinetic parameters could be different for variation rotation speed and ball sizes. The effects of ball size and particle size on the grinding kinetic were quantitatively confirmed.
The particle size distribution and particle morphology evolution of calcite powders were studied as a function of ball to powder ratio. The calcite powders were milled using a planetary ball mill with different ball-to-powder ratios of 20:1 and 40:1 under the same experimental conditions. The influence of the ball-to-powder ratio on particle size changes and morphological evolution of the milled calcite powders has been examined by a particle size analyzer (PSA) and scanning electron microscopy (SEM). The particle size and morphology evolution of calcite powder changed as ball size and BPR varied. Compared with the samples with a BPR of 20:1 and 40:1 under the same experimental conditions, the calcite powders with a BPR of 40:1 experienced it was de-agglomerated, fabricated finer and uniform powders, and particle size decreased. The result has been concluded as the increased frequency and intensity of particle and ball collisions.
Characteristics of spherical particles on copper powder and changing sizes were studied in a ball mill under various experimental conditions, such as different ball diameters, high rotation speeds, and milling times, using a discrete element method (DEM) simulation. This experiment has investigated the characteristics of spherical particle morphology evolution involved in the mechanical alloying of copper powder. The morphological evolution of the copper particle was analyzed using scanning electron microscopy (SEM). A spherical copper particle was shown with a roundness value using imageJ software. The DEM was used to simulate the ball motion in a planetary ball mill, and the impact energy and shear energy generated during the collision were analyzed to estimate the contact number between the ball and the ball wall. Therefore, as the size of the ball decreased, the number of ball-to-ball and ball-to-wall contacts increased accordingly, and the spherical shape of the copper powder changed.
Аж үйлдвэрлэлийн хурдацтай хөгжил, уул уурхай, үйлдвэрлэл, техник технологиуд тасралтгүй хөгжихийн хэрээр тэдгээрийн хэрэглээ, хэрэгцээ, шаардлагууд улам нэмэгдэж байдаг. Үүний үр дүнд бидний хүрээлэн буй орчин болох агаар, ус, хөрсөнд хорт бодисууд хуримтлагдаж улмаар байгаль орчин, хүн, мал амьтны эрүүл мэндэд ноцтой сөрөг нөлөө үзүүлж байгаа нь манай орны хувьд тулгамдаж буй асуудлууд юм. Тиймээс энэхүү судалгааны ажлаар байгалийн нөөцийг эдийн засгийн эргэлтэд оруулах, байгалийн гаралтай хүний эрүүл мэндэд хоргүй шингээгч материалын сонголтод цеолит нь ион солилцооны өндөр идэвх, сүвэрхэг шинж чанараар төгс тохирсон эрдэс бөгөөд энэ шинж чанар дээр үндэслэн хямд, үр ашиг өндөртэй шингээгч композит материал гарган авч, тасралтгүй урсгалтай баганан шингээлт явуулах замаар хар тугалгаар бохирдсон усан уусмалаас хар тугалгыг бууруулах туршилтыг гүйцэтгэлээ. Байгалийн цеолитыг натрийн алгинат полимер материалтай хольж бөмбөлөг хэлбэрийн шингээгч материал гарган авсан. Гарган авсан композит материалаар баганан шингээлтийг явуулан шингээлтэд нөлөөлөх баганын голлох параметрүүд болох баганын эзлэхүүн, шингээгч материалын хэмжээ, бохирдсон уусмалын анхны концентраци, уусмалын эзлэхүүн зарцуулалтыг нөлөөг судаллаа. Цеолитын найрлага болон хар тугалганы концентрацийн өөрчлөлтийг багажийн шинжилгээ (XRD, XRF, AAC) хийсэн. Баганын эзлэхүүнийг 2.5 см3 - 5 см3 болгож ихэсгэх үед шингээлтийн эхний цэг дэх анхны уусмалын концентраци болон шингээлтийн дараах концентрацийн (C/C0) харьцаа 3 дахин ихэссэж хар тугалганы бохирдлыг 60%, 88%-иар тус тус бууруулсан. Баганын эзлэхүүн тогтмол 5.0 см3 байх үед эзлэхүүн зарцуулалтыг 2.5 мл/мин - 6.25 мл/мин болгон хувьсгахад шингээлт 4 дахин багассаж хар тугалганы бохирдлыг 96%, 42%-иар тус тус бууруулсан байна. Баганан шингээлтийн үеийн нийт уусмалын эзлэхүүн 200 мл, эзлэхүүн зарцуулалт 6.25 мл/мин байх үед уусмалын анхны концентрацийг хувьсган туршилтыг явуулахад эхний цэгийн C/C0 харьцаа уусмалын концентраци ихсэх тусам дагаад ихсэж байсан. Төгсгөлийн цэгт өөрчлөлт ажиглагдаагүй. Баганын эзлэхүүн болон уусмалын анхны концентрацийг ихэсгэхэд гаргаж авсан композит материалын шингээлт нэмэгдсэн бол эзлэхүүн зарцуулалтыг нэмэгдүүлэхэд шингээлт буурч байна. Улмаар гарган авсан композит материал нь хар тугалганы уусмалын концентрациас хамааран 40-60% бууруулж байгаа нь ижил төстэй материалуудаас багтаамж өндөртэй хар тугалганы бохирдолыг бууруулахад үр нөлөөтэй байгааг тодорхойлсон.
Энэхүү судалгааны ажлаар байгалийн нөөцийг эдийн засгийн эргэлтэд оруулах, байгалийн гаралтай хүний эрүүл мэндэд хоргүй шингээгч материалын сонголтод цеолит нь ион солилцооны өндөр идэвх, сүвэрхэг шинж чанараар төгс тохирсон эрдэс бөгөөд энэ шинж чанар дээр үндэслэн хямд, үр ашиг өндөртэй шингээгч композит материал гарган авч, тасралтгүй урсгалтай баганан шингээлт явуулах замаар хар тугалгаар бохирдсон усан уусмалын бохирдлыг бууруулах туршилтыг гүйцэтгэлээ. Байгалийн цеолитод механик боловсруулалтыг гариган бөмбөлөгт тээрмийг ашиглан гүйцэтгэж, натрийн алгинат полимер материалтай бөмбөлөг хэлбэрийн шингээгч материал гарган авсан. Гарган авсан композит материалаар баганан шингээлтийг явуулан шингээлтэд нөлөөлөх баганын голлох параметрүүд болох баганын эзлэхүүн, шингээгч материалын хэмжээ, бохирдсон уусмалын анхны концентраци, уусмалын эзлэхүүн зарцуулалтыг нөлөөг судаллаа. Цеолитын найрлага болон хар тугалганы концентрацийн өөрчлөлтийг багажийн шинжилгээ (XRD, XRF, AAC) хийсэн. Баганын эзлэхүүнийг 2.5 см3 -5 см3 болгож ихэсгэх үед шингээлтийн эхний цэг дэх анхны уусмалын концентраци болон шингээлтийн дараах концентрацийн (C/C0) харьцаа 3 дахин ихэссэн. Баганын эзлэхүүн тогтмол 5.0 см3 байх үед эзлэхүүн зарцуулалтыг 2.5 мл/мин - 6.25 мл/мин болгон хувьсгахад шингээлт 4 дахин багассан байна. Баганан шингээлтийн үеийн нийт уусмалын эзлэхүүн 200 мл, эзлэхүүн зарцуулалт 6.25 мл/мин байх үед уусмалын анхны концентрацийг хувьсган туршилтыг явуулахад эхний цэгийн C/C0 харьцаа уусмалын концентраци ихсэх тусам дагаад ихсэж байсан. Төгсгөлийн цэгт өөрчлөлт ажиглагдаагүй. Баганын эзлэхүүн болон уусмалын анхны концентрацийг ихэсгэхэд гаргаж авсан композит материалын шингээлт нэмэгдсэн бол эзлэхүүн зарцуулалтыг нэмэгдүүлэхэд шингээлт буурч байна. Улмаар гарган авсан композит материалын шингээлтийн багтаамжийг тооцоход уусмалын концентрациас хамааран 40-60 мг/гр гэж гарсан нь ижил төстэй материалуудаас багтаамж өндөртэй байгааг тодорхойлсон.
The particle morphology and size changes in copper and iron powder were investigated using high-energy ball milling under the same milling experimental conditions. A particle size analyzer (PSA) and scanning electron microscopy (SEM) were used to control the particle size and morphology of powders. Therefore, we analyzed on the impaction of energy in the milling process using the discrete element method (DEM). The results show that the particle size of copper increased with increasing rotation speed and milling time. The particle morphology of copper powder changed to a spherical type. In contrast, iron powder showed size reduction instead of agglomeration. The morphologies of iron and copper particles were extremely different when compared under the same experimental conditions with the same energy. It was found that the experimental results varied depending on the characteristics of copper and iron powder.
Particle size and morphologies changes of calcite and iron powder were investigated using a planetary ball mill for studying grinding kinetics. Calcite and iron powders were analyzed using a particle size analyzer (PSA) and a scanning electron microscope (SEM). As a result of the grinding experiment, the particle size of iron powder and calcite powder changed with various experimental conditions. Powder size reduction is affected by the raw material characteristics under experimental conditions. There was a reduction in particle size even though iron powder and calcite powder had different properties.
The study has found enhancement in the mechanical properties of metal-based nano-composites by adding CNTs for a different raw material and particle morphology change on metal powder using ball milling process. The uses of metal alloys in some industries such as automotive have been limited by their substandard strength, rigidity, wear resistance, and hardness, compared metal based nano-composite materials. A scanning electron microscope (SEM) and field emission scanning electron microscopy (FESEM) were used to analyze the effect of particle morphology and sizes. After compacting, sintering, and rolling process, finally checked the hardness of the final products. Therefore, we studied the different experimental conditions on the impact of energy in the milling process on the discrete element method (DEM).
In this paper, a comparison of cellulose nanofiber (CNF) fabrication from Gelidium amansii using two kinds of grinding processes is presented. The cellulose from Gelidium amansii is pretreated with hydrogen peroxide and sodium carbonate in a separating and bleaching process. Then, two grinding processes (method A and B) are used to fabricate CNFs. The first is a traditional method of fabricating CNFs using a disc grinder, whereas the second method is identical to the first, but includes an additional step involving a planetary ball mill. In the new method (method B), dry cellulose powder is prepared using a planetary ball mill, which has the advantage of long-term storage and maintains the original quality of the cellulose. The morphological changes of the dry cellulose powder and CNFs are determined using scanning electron microscopy and field emission scanning electron microscopy. The physical characteristics of the CNFs are found to be significantly different when we change the disc grinder used in the grinding method to produce nanometer scale where the best result is homogeneous, uniform CNFs with a fabricated width of 19 nm.
