Atomistic Fabrication Technology to Enhance Accuracy

atomistic dissimulation engineering to Enhance AccuracyImportance of Atomistic Fabrication Technology to Enhance Machining Accuracy During Electrochemical Machining of MetalsRitesh Upadhyay, Arbind Kumar P.K. SrivastavaAbstractAtomistic trickery technology fully utilizes physical and chemical phenomena with atomistic and electronic understanding. In the eccentric of mechanical machining many defects argon introduced when pushing the official document on the takepiece bulge and then atoms on the subject fieldpiece surface are removed by the displacement and multiplication of such defects. Therefore many defects remain on the motionpiece surface after mechanical machining. Machining accuracy is considerably affected by disturbances such as thermal deformation and external vibration because remotion depth is dependent on the cutting depth of the tool and is precise difficult to manufacture precision crossroads by mechanical machining. In the case of atomistic fabrication tech nology surface atoms are naturally removed by chemical reaction ca utilize by reactive species and therefore no deformed layer on the workpiece surface. A very high-precision product potty be easily manufactured with st adequate to(p) physical and chemical phenomenon utilise for remotion reaction. In this paper possibility of atomic level remotion of work piece (Iron workpiece) have been explored. The on-going and voltage requirements for removal of a few(prenominal) thousand atoms will be calculated along with. the mechanism of removal of metals in relation with over-voltage and conductivity.IntroductionThe essence of na nonechnology is the ability to work at the molecular level, atom by atom, to create large body structures with fundamentally sunrise(prenominal) molecular organization. Compared to the behavior of single out molecules of about 1 nm (10 -9 m) or of bulk materials, behavior of structural features in the range of about 10-9 to 10-7 m exhibit important changes . Nanotechnology is concerned with materials and systems whose structures and components exhibit novel and significantly modify physical and chemical processes due to their nano descale size. The goal is to exploit these properties by gaining domination of structures and devices at atomic, molecular, and supramolecular levels and to learn efficient manufacturing and use these devices 1-4. Maintaining the stability of interfaces and the integration of these nanostructures at micron-length and macroscopic scales are all keys to success.New behavior at the nanoscale is not necessarily predictable from that observed at large size scales.The almost important changes in behavior are caused not by the put together of magnitude size reduction, but by newly observed phenomena innate to or becoming predominant at the nanoscale5-6. These phenomena include size confinement, prepotency of interfacial phenomena and quantum mechanics. Once it becomes possible to control feature size, it will in any case become possible to enhance material properties and device functions Being able to reduce the dimensions of structures down to the nanoscale leads to the unique properties of carbon nanotubes, quantum wires and dots Nanotechnology is the exploitation of the novel and modify physical, chemical, mechanical, and biological properties, phenomena, and processes of systems that are intermediate in size between isolated atoms/molecules and bulk materials, where phenomena length and time scales become comparable to those of the structure. It implies the ability to fall in and utilize structures, components, and devices with a size range from about 0.1 nm (atomic and molecular scale) to about 100 nm by control at atomic, molecular and macromolecular levels. Novel properties occur compared to bulk behavior because of the small structure size and short time scale of various processes7-8.Electrochemical chemical reactionWhen the occurrent passed through a NaCl electrolyte solutio n following reaction occureNaCl = Na+ + ClH2O = H + + OHThe positive ions moves towards cathode and negative ions moves towards anode. Each Na+ ions gain an electron and is converted to Na . Hence Na+ ions are reduced at the cathode by means of electrons.Cathode ReactionNa+ + e = NaNa +H2O = NaOH + H+2H+ + 2e = H2It shows that only hydrogen muck up evolve at cathode and there will be no bank depositAnode ReactionFe = Fe2+ +2eFe2+ + 2Cl = FeCl2Fe2+ + 2OH = Fe (OH)2FeCl2+ 2OH = Fe(OH)2 + 2Cl2Cl Cl2 + 2e2FeCl2 + Cl2 = 2FeCl3H+ + Cl = HCl2Fe(OH)2 +H2O +O2 = 2Fe(OH)3Fe(OH)3 + 3HCl = FeCl3 + 3H2OFeCl3 + 3NaOH = Fe(OH)3 + 3NaCl conjectural AspectsBuilding block atoms draw an important role in in store(predicate) atmostic fabrication technology. Material removal count for removal of Fe work piece at atomic level have been calculated by apply Faradays law.Where MRR = Metal Removal assess , A = nuclear weight, I = Current, Z = valency,F = faradays constant . The results are shown in puzzle out 1, common fig tree 1 dapple of Metal Removal identify against Current Density, A=55.85,Z=2,F=96500It is clear from the figure that very low current is needed for atomic scale removal of iron atoms from the iron work piece. The requirement of voltage for removal of iron at atomic scale have been calculated using ohms Law and shown in figure 2Fig 2 Plot of Metal Removal Rate against Voltage, where specific conduction=0.0387ohm-1 cm-1othersparameter are same as in figure 1.It is clear from the figure that voltage requirement is very low. The current and voltage data for removal of few thousand atoms shows that conductivity and over-voltage play important role in current carrying process.Effect of electrolyte conductivity on MRRElectrolytes are substances that become ions in solution and having capacity to conduct electricity. The electrolyte has trine main functions in the ECM process. It carries the current between the tool and the workpiece, it removes the product of the reaction from the cutting region, and it removes the heat produced by the current flow in the operation. Electrolytes must have high conductivity, low toxicity and corrosivity, and chemical and electrochemical stability. The set out of material removal in ECM is governed by Faradays laws and is function of current density which depends upon the submersion of electrolyte with increase in concentration of electrolyte the MRR increases continuously up to a limiting value after which if elevate increase in concentration is do the MRR decreases due to decrease in ionic mobility.Effect of Over voltageThe over-voltage is the important parameter which modify the material removal rate and is sensitive to tool viands rate and equilibrium machining spreadhead. Material removal rate decreases due to increase in over voltage and decrease in current efficiency, which is directly cogitate to the conductivity of the electrolyte solution.Over voltage was calculated asV = V where V = over voltage, V = applied voltage, = density of work piece, F = Faraday constant, K = conductivity / specific conductance of electrolyte solution, A = atomic number of work piece metal, Ye = equilibrium gap and f = tool feed rate. The variety of over voltage with equilibrium gap is shown in Figure 3 which indicate that over-voltage decreases linearity with increase in equilibrium gap. When equilibrium gapapproaches to zero, over voltage approaches to applied voltage. Figure 4 shows variation of tool feed rate with overvoltage, which shows that over voltage decreases sharply with penetration rate and goes to negative side after a certain tool feed rate. Negative value of V, seems to be unreal because un-matching long range set of penetration rate for single fixed value of equilibrium gap.Fig 3. Plot of Over voltage against equilibrium machining gapFig 4. Plot of over voltage against penetration gapConclusionThe effort is made to focus on the importance of atomistic fabrication technolo gy with the outcome of key factors like over voltage and electrolyte concentration influencing the quality of machined surface and dimensional accuracy. The application of this technology during machining of metals and alloys proves that the electrochemical reactions can be used for nanometer accuracy, which allows high precision machining.The set up including power supply, electronic circuit, tool and electrolyte feed devices have been proposed to perform nano electrochemical machining in modulate to enhance the machining accuracy.ReferencesMukherjee S.K, Kumar S , and Srivastava P.K effect of electrolyte on the current- carrying process in electrochemical machining. J . Mechanical design Science 221,1415 -1419 2007.Stotes J, Lostao A, Gomez C, Moreno , Baro A.M. Jumping mode AFM resourcefulness of biomolecules in the repulsive electrical double layer ultra microscopy 1-6 2007.McGeough, J.A. principles of electrochemical machining chapterIII (chapman,Hall.London) 1974.Ma, and R . Schuster, Locally enhanced cathodoluminescence of electrochemicallyfabricated gold nanostructures, Journal of Electroanalytical Chemistry, vol. 662, pp. 1216, 2011.McGenough J A, Leu M, Rajurkar K P, et al. Electroforming process and application tomicro/macro manufacturing. CIRP AnnalsManufacturing Technology, 50(2) 499-514, 2001.Zhang Z Y, Zhu D, Wang M H. Theoretical and experimental research into electrochemicalmicromachining using nanosecond pulse Chinese Journal of Mechanical Engineering43(1) 208-213, 2007 in Chinese.Lee E S, Baek S Y,Cho C R. A study of the characteristics for electrochemical micromachining withultrashort voltage pulses The internationalist Journal of Advanced Manufacturing Technology 31(7-8)762-769, 2005.Schuster R., Kirchner V, Allonue P, and Ertl G, Electrochemical micromachining, Science 289, 98101_2007.Datta M, Shenoy R. V, and Romankiw L. T, late advances in the study of electrochemicalmicromachining, ASME J. Eng. Ind. 118, 2936,1996.Datta M, Microfa brication by electrochemical metal removal, IBM J. Res. Dev. 42, 655669,1998.Rajurkar K.P, Kozak J, and Wei B, Study of Pulse Electrochemical Machining Characteristics AnnalsInternational College for Production seek Vol. 42, 231-234, 1993.Hocheng, H., Kao, P. S. and Lin, S. C., Prediction of the Eroded Profile during ElectrochemicalMachining of Hole, Proc. JSME/ASME Int. Conf. Materials and Processing, pp. 303_307 (2002).Keown, Mc. P. A., The Role of Precision Engineering in Manufacturing of the Future, Annals CIRP,Vol.36, pp. 495_501 (1987).Electrochemical Machining in Production Technology, HMT, Bangalore, Tata McGraw Hill make Company, New Delhi, India, p. 478 (1980).