Papers by Keyword: Ball Mill

Abstract: The processing of binary alloys consisting of ferromagnetic Fe and antiferromagnetic Cr by severe plastic deformation (SPD) with different chemical compositions has been investigated. Although the phase diagram exhibits a large gap in the thermodynamical equilibrium at lower temperatures, it is shown that techniques based on SPD help to overcome common processing limits. Different processing routes including initial ball milling (BM) and arc melting (AM) and a concatenation with annealing treatments prior to high-pressure torsion (HPT) deformation are compared in this work. Investigation of the deformed microstructures by electron microscopy and synchrotron X-ray diffraction reveal homogeneous, nanocrystalline microstructures for HPT deformed AM alloys. HPT deformation of powder blends and BM powders leads to an exorbitant increase in hardness or an unusual fast formation of a σ-phase and therefore impede successful processing.

Abstract: Nano-sized chitosan has been prepared by ball mill (High Energy Milling) with 1500 rpm to determine itsgrainz size and functional group. A nanopowder sample was prepared in the various milling time of the precusor. The milling time were 60, 120, 180, 240, 300 and 360 minutes. The Scanning Electron Microscopy (SEM)images indicated that the microstructures and grain size of as-prepared chitosan changed by increasing the milling time. The average of grain size is 15,1 nm. The Fourier Transform Infra-Red (FTIR) spectra showedthat the -OH bond shifted after milling process. The new C=O roups formedduring the milling process, because of the ordered microstructures in the nano-sized chitosan granules weredestroyed after ball millingThe surface area of the nano-sized chitosan was high, the particles tend to agglomerate since the ionic electrostatic could not prevent to form the agglomeration. The ball milling treatment was an effective method to reduce the grain size of chitosan, and functional groups will not automatically change during the milling process.

Abstract: The paper describes the study of mechanical activation of multi-component ceramic powder materials based on boron nitride. The mechanical activation of the powders was carried out according to the best optimal parameters in a ball mill AGO-2U. Increasing the time of mechanical activation leads to more fine-grained powders. We described the technique of mechanical activation of ceramic powder materials. We introduced the results of X-ray diffraction analysis of the ceramic powder cBN, cBN-Co, hBN-Co before and after mechanical activation. We generated mathematical equations of dependence of an average powder particle size on the average mechanical activation time. We described how the crystal lattice "a" parameters and unit cell volume "V" of cBN and hBN powders depend on mechanical activation time. We studied the chemical composition of powder materials. We also studied the structural parameters of ceramic powders.

Abstract: Portland cement got his name derived from the appearance of concrete that resembles sandstone located near city of Portland in England. In 1824, John Aspdin was granted a patent for the production of Portland cement.In the past, energy and economic demands on production of cement were lower than they are today. Production was characterized by a slower burning mode and coarser grinding. Product produced this way were reaching lower compressive strength.Currently there are several companies producing Portland cement. Main ones in Czech Republic are Holcim, Heidelbergcement group and Lafarge Cement a.s. Their production methods are very similar. The differences are mostly in the possibility of using local raw materials with different chemical composition and the technical equipment of factories. In the production, the main emphasis is on reducing energy and financial cost.One way to save energy and money is to use mechanical-chemical activation when grinding Portland clinker.

Abstract: This paper made the detailed discourse for the study on using cellulase, hemicellulase hydrolysis of poplar fiber raw material to make glucose. The raw material used in this experiment is poplar, cellulase and hemicellulase enzymes are used. Hemicellulase is a complex system, xylose is regarded as the main chain for a lot of hemicellulose. The experiment used dry poplar as raw material, through the ball mill, ground poplar into wood powder. In the experiment, the optimal condition of enzyme hydrolysis of wood powder has been discussed based on reaction temperature, reaction time, enzyme concentration, and the pH value of reaction. Finally, under the optimal condition, use enzyme to hydrolyse wood powder, measure reducing sugar content by the DNS method, and calculate the rate of hydrolysis.

Abstract: The motion equation of the grinding cylinder is deduced, which is based on the dynamic analysis of the grinding cylinder of the ball mill coupled with vertical vibration. Numerical model of vertical vibration ball mill is built and used to study the motion of grinding cavity media and grinding efficiency. The simulation results show that the distribution status of the grinding media in each region is changed, the grinding fragmentation of the grinding media to the material is enhanced, and the efficiency of fine grinding is improved with the coupled vertical vibration in a ball mill.

Abstract: In the numerical control turning processing, for some of the special contour parts, G71 and G73 instructions are difficult to handle.The ball tool is often used for turning,but the programming is more complex.By the system macroinstruction of FANUC-0iCNC system, this paper writes the preparation of the outer contourloop, thus simplifying the ball tooling special parts operating procedures, and the processing efficiency is improved .

Abstract: In order to provide evidence for the adjust of grinding rate, we have did the experimental study on the grinding rate with different grinding concentration of Dahongshan copper, the tests indicate that the best grinding concentration and grinding rate of Dahongshan copper is 70% and 100%.

Abstract: In order to provide evidence for the adjust of grinding concentration, we have did the experimental study on the grinding concentration of Dahongshan copper, the tests indicate that the best grinding concentration of Dahongshan copper is 70%. Generally, the advantage range of fine grinding concentration is from 65% to 75%,so we choose the acceptable range of grinding concentration from 65% to 70% .

Abstract: The ball mill is one kind of breaking plants which used widely in building materials, metallurgy, mineral processing and so on. The finite element method is used to build the model of the 7.32× 11.28 overflow type ball mill. And then modal analysis of oversize ball mill tube is carried out by ANSYS workbench, which leads to the intrinsic frequency and model of vibration of tube. The analysis result can be reference for the design of ball mill.