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Showing 1 to 20 of 29 for “"Milling time"”.
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The Effect of Milling Time on the Structure and the Properties of Mechanically Alloyed High Carbon Iron-Carbon Alloys
The effects of mechanical alloying milling time and carbon concentration on microstructural evolution and hardness of high-carbon Fe-C alloys were investigated. Mechanical alloying and powder metallurgy methods were used to prepare the samples. Mixtures of elemental powders of iron and 1.4, 3, and …
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Mechanically Processed Alumina Reinforced Ultra-high Molecular Weight Polyethylene (UHMWPE) Matrix Composites
… fraction of the monoclinic phase increased with milling time, mostly at the expense of the amorphous phase. The melting temperature decreased as a function of milling time as a result of modifications in the UHMWPE molecular structure caused by the milling. At the same time, for a given alumina …
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Consolidation of WC-Co nanocomposites synthesised by mechanical alloying
The influence of mechanical alloying (MA) milling time, temperature, sintering method and microstructure on the mechanical properties of a tungsten carbide-cobalt (WC-Co) hardmetal, based on 10wt% Co, has been established. The effects of high-energy milling for 30, 60, 180 and 300 min and the …
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Microstructural Engineering of Titanium-Cellulose Nanocrystals Alloys via Mechanical Alloying and Powder Processing
… as to reduce to cost of production. Vibrational milling using a SPEX 8000M mill was used to mechanically alloy titanium powder with varying concentrations of CNCs. Additionally, the milling time was varied. This process showed that varying the concentrations of CNCs between 0.5% - 2% by weight …
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The role of microstructure on the combustion and impact behavior of mechanically activated nickel/aluminum reactive composites
… Ni and Al powder is mixed by High-Energy Ball Milling (HEBM) to produce a mechanically activated (MA) Ni/Al reactive composite. A two-step process is adopted that includes dry milling followed by wet milling using hexanes as a process control agent. The microstructure of the resulting powder …
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On a Bimodal Distribution of Grain Size in Mechanically Alloyed Bulk Tungsten Heavy Alloys
… the small-grained region increased linearly as milling time increased. A slice from a sintered sample was prepared for examination by TEM, in which particles 30–100 nm in diameter were regularly observed on the boundaries of the 200–600 nm grains. EDS point analysis showed that the particles are …
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Powder Processing and Characterization of W-3Ni-1Fe Tungsten Heavy Alloy
… depleted uranium in kinetic energy penetrators. Milling time and sintering temperature were varied from 15 to 100 hours and 1000 to 1300°C respectively. Particle size analysis and SEM showed a bimodal particle size distribution with most of the particles below 10 µm in size. XRD peak broadening …
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Production of strengthened copper materials by Mechanical Milling-Mechanical Alloying and Spark Plasma Sintering
… In this PhD thesis initially mechanical milling (MM) has been considered as suited strengthening technique due to the severe strain hardening and microstructural refinement induced by severe plastic deformation during the process. Then an enhanced hardening has been obtained by dispersion …
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Structural Evolution In Mechanically Alloyed Fe-based Powder Systems
… evolution in these powders as a function of milling time during mechanical alloying. Blended elemental powders of Fe100-XBX (where x = 5, 10, 17, 20, 22, 25, 37.5 and 50 at. %) and a bulk metallic glass (BMG) composition (Fe60Co8Zr10Mo5W2B15) were subjected to mechanical alloying in a SPEX …
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Processing and Properties of Particulate Reinforced Carbon Matrix Composites
… together at two different compositions and milling times. Experimental conditions consisted of replicates of three bulk samples made from uniaxially pressed powder mixtures heat treated from 800 °C up to 1200 °C in increments of 100 °C. Heat treatment occurred in a tube furnace with a …
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Characterizing the Effects of Mechanical Alloying on Solid State Amorphization of Nanoscaled Multilayered Ni-Ti
… of Ni and Ti was cryomilled with varying milling times to create Ni-Ti lamella structures with average spacings of 50 nm, 470 nm, and 583 nm in powder particles to vary the interfacial surface area per volume. These surfaces form interfaces for diffusion that are essential for solid state …
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Organic complexes of unrefined and milled kaolin: An infrared spectroscopic study.
… and industrially significant organic molecules. Milling and temperature were found to affect the structure of kaolin and types of surface sites present. These changes were monitored primarily by variable temperature diffuse reflectance infrared Fourier transform spectroscopy (VT DRIFTS) and other …
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A study of mechanochemical activation in solid-state synthesis of advanced ceramic composites
… synthesis of various compounds. Intensive (dry) milling of ultra-fine and nanometer-sized powders is considered to be a way of applying “mechanochemical activation” that involves dispersion of solids, generation and migration of defects in the bulk and plastic deformation of particles. Taking …
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A study of the mechanisms of milling-induced enhancement of solubility and dissolution rate of poorly soluble drugs
Milling and co-milling are well known techniques that have potential to enhance the solubility and/or dissolution rate of poorly soluble drugs. There are broadly two aims for this project. The first was to develop an understanding of how individual and combination of techniques may be used to …
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Processing of Aluminum Alloys Containing Displacement Reaction Products
… relationships developed between the initiation time of the reaction and the mechanical alloying charge ratio. The exponential relationships were the result of changes in the intensity and quantity of collisions occurring during mechanical alloying. Differential thermal analysis of the …
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Discrete element method based scale-up model for material synthesis using ball milling
Mechanical milling is a widely used technique for powder processing in various areas. In this work, a scale-up model for describing this ball milling process is developed. The thesis is a combination of experimental and modeling efforts. Initially, Discrete Element Model (DEM) is used to describe …
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Fabrication of metal-oxide modified porous ceramic granules from aluminosilicate clay soils for defluoridation of groundwater
… area of 50.5228 m2/g at 30 min activation time. Hence, the optimum activation time was 30 min. The Fourier Transform Infrared (FT-IR) analysis showed increase in the absorbance of FT-IR by Si-O-H groups at 510 cm-1 with increasing milling time. This is evidence that more surface Si-O-H …
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Design of Titania Photocatalytic Membranes containing Fine Ceramic Fibres
… sol-gel into circular moulds. Effects of fibre milling time and fibre to sol-gel ratio on their performance were studied, besides mechanical properties, porosity and specific surface area. Their flow properties and photocatalytic efficiency were also examined. Due to the availability of these …
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The Effect of Carbon Concentration on the Amorphization and Properties of Mechanically Alloyed Cobalt-Carbon Alloys
… were milled for up 40 hours. After 20h of milling some of the alloys (≤ 20 at.% C) had partially amorphized, while the higher concentrations had completely amorphized. After 40h of milling, complete amorphization was observed in all alloys, except for the 2 and 5 at.% C alloys. The thermal …
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Development of nanocrystalline Fe80Cr20 alloy using combination technique of ball milling and ultrasonic treatment for fuel cell interconnector
… of this study is to explore the high energy ball milling (milled) combined with ultrasonic treatment (UT) in obtaining smaller crystallite size, finer surface morphology, higher thermal stability and more homogenous nanocrystalline Fe80Cr20 alloys. This condition was motivated by the previous …
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