High-energy Ball-milling Machine Research Articles

Effect of Milling on Dielectric Properties of PZT

In this study, we investigated the impact of high-energy milling on the structural and dielectric properties of Pb[Zr(1-x)Tix ]O3 [PZT] ceramics synthesized using the solid-state reaction process. The sample was milled for 2, 4 & 6 hours using a high-energy ball milling machine. The unit cell structure for all of the samples was observed to be monoclinic, according to x-ray diffraction measurements (space group: C1m1). A significant reduction in crystallite size was observed, from 132 nm to 46 nm after 6 hours of milling. The dielectric study indicated a classical ferroelectric type behaviour for the un-milled sample and diffused phase transition for all milled samples. However dielectric constant dropped from 940 to 487 after 6 hours of milling.

Eco-friendly produced superfine Moringa oleifera nanometric food powder and its characteristic effect on its structural, morphological and toxicity for varied applications as new functional nanomaterials

The present study investigates the characteristic changes brought in the structural and morphological properties of the Moringa oleifera leaf superfine nanoscale powder synthesized via High Energy Ball Milling machine and characterized by employing modern scientific tools. Moringa oleifera leaves were procured locally. The leaves were thoroughly washed with DI water to remove any contaminants followed by drying in laboratory using micro-wave oven at 50°C. The dried leaves were then ground coarsely in the mixer grinder for 10 min. Part of the coarsely ground powder was labelled as 0 hrs. and kept in an airtight container for further use. The remaining moringa oleifera powder was milled for 2.5 hrs., 5 hrs., and 7.5 hrs. respectively in High Energy Ball Milling Equipment. The XRD studies showed that the crystallites size of milled moringa oleifera powder was between 1 nm and 100 nm. The present study reveals surface morphology and crystal structure alteration due to different milling times. The TEM studies showed that the milled nano powder is below 50 nm. UV–vis measurement shows that maximum absorbance for all four samples (MS 0 hr., MS 2.5 hr., MS 5 hr. & MS 7.5 hr.) was nearly identical at 400 nm and slightly lower at 270 nm and substantial absorption at about 650 nm within the visible spectrum, which could be attributed to the fact that there is the presence of protein and cellulose content in the samples. There was a considerable change in wavenumber but no change in the functional group was witnessed in FTIR at different milling times. A biomedical assay was also studied to check the cell viability and cytotoxicity. The test used was MTT Assay; it is a colorimetric assay that is routinely employed in the fields of bio-medical science and biotechnology. It is the conversion of yellow-coloured tetrazolium salt to purple-coloured formazan using NADPH present inside the cell. The results indicated that cell viability also increases by increasing the milling hours. A dosage of 25 µg/ml seems to be optimal for maintaining cell viability. The present research opens a new window in the field of food science & Agriculture that superfine nanoscale powder as a new functional material for its various uses in Biomedical engineering, Food, Health and related sector.

An assessment on the effect of titanium dioxide & iron oxide nano-particles in industrial waste water decontamination

The aim of this paper is to identify a technique to detoxify the industrial waste water using metal oxide nanoparticles. Waste water from manufacturing or chemical processes in industries contributes to water pollution. Industrial waste water usually contains specific and readily identifiable chemical compounds. It destroys aquatic life and reduces its reproductive ability. Eventually it is hazardous to human life. Most major industries have treatment facilities for industrial effluents but this is not the case with small-scale industries, which cannot afford enormous investments in pollution control equipment. In this paper, an experimental study was conducted to study the effect of titanium dioxide and ferric oxide nanoparticles in detoxification of industrial waste water. Here the adsorption property of these nanoparticles was used for the detoxification of industrial waste water. The nanomaterials were synthesized using high energy ball milling machine and the characterization was done through scanning electron microscopy. After the preparation, these Nano sized titanium dioxide and ferric oxide powder were introduced to the pretested waste water. Due to the adsorption property of these nanomaterials, it is observed that the contaminants like sulphate, cadmium, lead and chlorides are adsorbed to some extent.

Studies on mechanical and thermal behaviors of Al6061- SiC-Gr-ZrO2 nanohybrid composites

The aim of this research work is to fabricate hybrid nano composite material containing metal matrix Al6061, reinforcements of Silicon Carbide (SiC), Zirconia or Zirconium dioxide (ZrO2) and Graphite (Gr) by a novel technique. These reinforcements are added by an increment of 0.75% for each sample. A high energy ball milling machine is used to create nano particles for fabrication of new material. These materials are united by advanced stir casting process. Then nano composite specimens are prepared to suit for hardness, tensile and thermal conductivity tests. Hardness of the composites has significantly improved by the presence of reinforcement content. Then the Tensile strengths are increases as well as decreases with enlarged amount of reinforcements. Also the effect of thermal conductivity shows addition of reinforcements decreases the value of thermal conductivity. Then finer bonding was achieved in between reinforced particles and matrix as observing in SEM. This will shows that the newly fabricated materials are suited for aerospace and automotive applications.

Influence of temperature on microstructure, structural and ferroelectricity evolution properties with nano and micrometer grain size in multiferroic HoMnO3 ceramics

The influence of temperature on microstructural, structural and ferroelectric evolution properties of multiferroic holmium manganese oxide (HoMnO3) ceramics were investigated. HoMnO3 ceramics were synthesized using a mechanochemical reaction of Ho2O3 and Mn2O3 powders in a high energy ball milling machine. The powder were sintered from 600 to 1250 °C with 50 °C increments. The results shows the microstructural, structural and ferroelectric hysteresis loop were observed to be dependent on sintering temperatures. The XRD characterization suggests an improvement of crystallinity with increasing sintering temperature. The hexagonal HoMnO3 were observed at temperature ≥1200 °C with the grain size of around 1600 nm. SEM micrographs showed larger grain size as the sintering temperature increased. The SEM results revealed a transformation of crystal structure occurs from orthorhombic to hexagonal at larger grain size regime. Polarization P—electric field E ferroelectric properties were observed to be enhanced with the increase of grain size through sintering temperature. The ferroelectric behavior was observed to change with the change of microstructure along with the structure transformation from orthorhombic to hexagonal. A complete systematic studies of the micron-nanometer grain size on microstructure-properties evolution of HoMnO3 multiferrroic ceramics is higlighted.

Fabrication of cast carbon steel with ultrafine TiC particles

The carbon steels dispersed with ultrafine TiC particles were fabricated by conventional casting method. The casting process is more economical than other available routes for metal matrix composite production, and the large sized components to be fabricated in short processing time. However, it is extremely difficult to obtain uniform dispersion of ultrafine ceramic particles in liquid metals due to the poor wettability and the specific gravity difference between the ceramic particle and metal matrix. In order to solve these problems, the mechanical milling (MM) and surface-active processes were introduced. As a result, Cu coated ultrafine TiC powders made by MM process using high energy ball milling machine were mixed with Sn powders as a surfactant to get better wettability by lowering the surface tension of carbon steel melt. The microstructural investigations by OM show that ultrafine TiC particles are distributed uniformly in carbon steel matrix. The grain sizes of the cast matrix with ultrafine TiC particles are much smaller than those without ultrafine TiC particles. This is probably due to the fact that TiC particles act as nucleation sites during solidification. The wear resistance of cast carbon steel composites added with MMed TiC/Cu-Sn powders is improved due to grain size refinement.

Effect of ball milling on the characteristics of nano structure SrFeO 3 powder for photocatalytic degradation of methylene blue under visible light irradiation and its reaction kinetics

In this report, SrFeO 3photocatalyst powder was synthesized by a high temperature solid state reaction method and the size of the particle was reduced with a high energy ball milling machine. The morphology, crystalline structure, particle size and size distribution of obtained samples were characterized by energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV–vis spectrometer, scanning electron microscope (SEM), and transmission electron microscopy (TEM). Photocatalytic activity of the prepared samples was investigated by photodegradation of methylene blue (MB). The obtained results show that the SrFeO 3 sample works as photocatalyst and by reducing the particle size using high energy ball milling method for 5 h milling, particles with 19–25 nm crystallite size exhibit maximum activity due to larger surface area. The photocatalytic activities of the powders were investigated and kinetics of reaction was modeled by using high performance liquid chromatography (HPLC) and Mass spectroscopy. Photocatalytic activities of these powders increase with decreasing particle size.

Anisotropic PrCo$_{5}$ Nanoparticles by Surfactant-Assisted Ball Milling

Magnetically hard PrCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sub> nanoparticles have been produced by using surfactant-assisted high-energy ball milling techniques. The use of surfactant leads to the dispersion of the crashed particles and prevents them from rewelding during the milling process. Heptane was used as the milling medium, and oleic acid as the surfactant. High-energy ball milling experiments took place in a milling vial with steel balls by using a Spex 8000 M high-energy ball milling machine. The coercivity was found to increase with milling time with a value of 6.8 kOe after 12 h of milling. TEM data showed that the milled powders consist of nanoparticles with an average size of 8-10 nm.

Anisotropic Sm-(Co,Fe) nanoparticles by surfactant-assisted ball milling

Magnetically hard Sm2(Co0.8Fe0.2)17 and SmCo5 nanoparticles have been produced by using surfactant-assisted low- and high-energy ball milling techniques. Surfactants prevent the rewelding of the crashed particles during the milling process. Heptane was used as the milling medium and oleic acid as the surfactant. High-energy ball milling experiments took place in a milling vial with carbon steel balls by using an SPEX 8000M high-energy ball milling machine. The coercivity was found to increase with milling time with values of 2.3 kOe for Sm2(Co0.8Fe0.2)17 and 18.6 kOe for SmCo5 after 4 h of milling. Transmission electron microscopy data showed that the milled powders consisted of nanoparticles with an average size of 5–6 nm and a narrow size distribution. Samples deposited on copper coated carbon grid showed self-assembled nanoparticles which could be further aligned when subjected to a magnetic field.

Effect of Nb and Sn on the Transformation of α-Ti to β-Ti in Ti-35 Nb-2.5 Sn Nanostructure Alloys using Mechanical Alloying

This study was conducted to observe the phase transformation of Ti-35 %Nb-2.5 %Sn during milling for various milling times using a mixing machine and a high-energy ball milling machine (HEBM). In this work, niobium was chosen as the β stabilizer and tin as the reducer of the elastic modulus. The starting materials were blended and milled in a mixing machine (24 h) and a high-energy ball mill machine (1 h, 4 h, and 12 h). The particle sizes and phases of the produced powders were analyzed using XRD, SEM, TEM, and PSD; the titanium was found to be fully transformed from the α phase to Ti the β phase Ti after 12 h of milling.

NiAl Shape Memory Alloy by Powder Metallurgy Method

Mechanical alloying in high-energy ball-milling machine was used to fabricate the NiAl shape memory alloy. The effect of milling time on the mechanical properties was investigated. The microstructures and phase transformations of NiAl were studied by scanning electron microscope (SEM), x-ray diffraction (XRD), differential scanning calorimetry (DSC) and dynamic thermal analysis (DTA). Lamella micro-structures was found in the SEM examination and they were confirmed to have the martensite structure by XRD analysis. Results from DSC thermal analysis revealed that the sintered-compact exhibited thermoelastic transformation. Besides, the martensitic transformation was found to have suppressed by the presence of Ni 5 Al 3 precipitates in some of the ball-milled specimens.