The Process of Electrochemical Machining - Essay Example

Electrochemical Machining Introduction To date in the metal industry Electrochemical Machining (ECM) commonly referred as nontraditional or nonconventional machining method has undeniably proved to be extremely beneficial based on its varied applications (Singal, Mridul & Rishi, 2008). This is contrary to the former approaches whereby presently it has enabled experts and manufacturing engineers utilize to improve varied sophisticate components like those preferred to be in the aerospace, implant and automotive sectors (Singal, Mridul & Rishi, 2008). Since most of the metals in the pure state without undergoing any treatment might not serve the intended roles mostly emerging with the current technological knowhow. Utilizing Faraday’s laws of electrolysis, machining is normally by way of controlled removal of metal through dissolution an electrolytic cell’s anode (Singal, Mridul & Rishi, 2008). Hence, initiating a current if the electrolyte in which the poles are immersed (in aqueous like NaCl) can adequately allow movement of atoms in such a way it ensures conduction process. The core principle that characterizes this process encompasses rapid as well as selective dissolution of the work piece intended to be machined, which acts as an anode and the released components attach themselves on the cathode normally linked to a D.C (Setchi, Howlett, Naim, & Seinz, 2014). Therefore, this study seeks to avail sufficient and precise information regarding ECM process coupled with how current technological knowhow has embraced it in varied applications. The Process Mainly, this approach usually utilizes electrolysis process with aid of D.C linked to the cathode and the +ve electrode being the work piece as evident in Figs 1, 2 & 3. Figure 1: EMAG. (2015). Simplified Cross Section of ECM process arrangement. Retrieved from The process entails immersion of both the work piece and anode in the electrolytic aqueous, which in this case it might be NaCl or NaNO3 (Setchi, Howlett, Naim, & Seinz, 2014). The creation of potential between the electrodes takes place with the intention of initiating D.C that will facilitate anode dissolution. It is also through use of D.C that facilitates flow of electrons from the piece intended to be worked on goes to the cathode, hence initiating gas release. In the industrial settings as depicted in Figs 2 and 3, it entails immersing or placing the work piece in an electrolyte and linking to high current power source through the +ve terminal (Singal, Mridul & Rishi, 2008). Then the cathode tool to the –ve side and shaped in such a way to fit effectively in the anode’s cavity without making any contact. Figure 2: SubsTech. (2013). Electrochemical Machining Process. From Figure 3: SubsTech. (2013). Electrochemical Machining Equipment or plant. From Even flow of the electrolyte with an approximate 5m/s velocity amid the electrodes is by the aid of a recirculation pump. This is to intensify both mass and charge movement especially through the created sub layer adjacent to the anode piece (Abdel-Gawad, 2013). To maintain the extent of gap between the tool and work piece, in certain circumstances industries usually use servomotors. This is to ensure the distance amid them is small thus reduce resistance that might render the process ineffective or taking too long. Dissolution in this case is due electrical current whereby the tool reproduces itself on the anode because of the constant electrolyte’s flow whereby its roles encompass; Availing medium of the electrolysis process Dissipating heat generated due to high D.C as it flows through the electrodes. Chemical actions that characterize each electrode include; Cathode The action encompasses liberating of OH- ions as well as freeing of Hydrogen (Singal, Mridul & Rishi, 2008). M+ + ē M (Metal e.g. Fe) 2H+ + 2ē H2 (Gas Evolution) Work Piece (Anode) The OH- ions produced in the tool then combines with those of the ion to form solid metal hydroxides thus eliminating metal from the anode or work piece (Singal, Mridul & Rishi, 2008). M M+ + ē (Dissolution Process) 2H2O O2 + 4H+ + 4ē (Oxygen creation) 2Cl- Cl2 + 2ē (Halogen gas creation) Applications Studies so far conducted scholars and experts contend ECM’s compared to other processes has numerous industrial uses (El-Hofy & Youssef, 2008). This is because of the process’ ability to apply adequately on numerous materials without any significant defects so long they are electrical conduct. Hence, implying the only limitation that would bar working on a certain material is its own ability to conduct electricity as necessitated but not hardness or strength (El-Hofy & Youssef, 2008). In addition, this approach through varied modifications based on what material or results required can adequately used in; Turning Slotting Trepanning Profiling ECM has also known to enhance tools especially those used in intensive wearing areas like drilling as well as those involve constant heat generation. Since the original state of the metal materials will not withstand harsh temperatures. Some of the sectors whose tools entail worked on using ECM embrace; Aerospace (e.g. Jet Turbine and Engines) Automotive (e.g. Break systems) Biomedical (e.g. Artificial implant) Chemical (e.g. reactors) Consumer merchandise (like Watch industry) Limitations Compared to the numerous benefits licked to this method, its limitations are few though serious in certain settings. For instance, Pletcher (2013) in his study contends the core drawback encountered when utilizing this process is the need to end up designing cathodes for each new jobs. Hence, becoming extremely tiresome and bothering since the former cathode may not even apply anywhere once the process that was underway comes to completion. In addition, destructive localized corrosion is the core characteristic of this process due to action of anodes besides being extremely tricky in the case of disposing the electrolyte safely (Trethewey & Roberge, 2012). Consequently, this makes the process being costly in terms of ensuring environment’s safety and designing of cathode before commencing of a new job, which a given firm ought to undertake. Economics Economics of this approach significantly relies on materials as well as applications choices. For instance, suppose the operation designed to commence is simple or if the material set for advancement one can utilize other means then embarking on using other approaches is a justifiable move. This is instead of using ECM, which in that situation may proof to be extremely pricey. Hence, this implies economics of this process primarily depends on its applications and other choices that may be appropriate or unjustifiable in fashioning a certain material. In ascertaining its economics in regards to fashioning a certain material, experts usually assess the cost of the entire process and design variables against benefits anticipated in comparison to other approaches that might be cheaper. Design considerations and defects Before employing ECM, it entails coming up with an appropriate cathode tool that will guarantee D.C flow and ensure continuance of the process until it realizes its core intent, which is metal removal. In addition, the work piece and cathode gap separating them ought to be small but not in contact in order to reduce resistance and rendering the process taking long. Hence, ease rate of dissolution, which is also accelerated by recirculation pump that ensures constant flow of the electrolyte at 5m/s velocity. However, is during ECM electrolyte baths are not agitated appropriately by ensuring a minimum of 5m/s flow, then worked on materials may develop micro surface defects (Mcgoldrick, 2013). These defects usually prompt worked on materials loose industrial since they cannot be redone but eliminated with the aid of hand, which ought not to be the case. Since worked piece its surface ought to be transformed through electrolysis but not through hand whereby the latter leaves some areas of the surfaces not well treated. References Bottom of Form Abdel-Gawad, E. H. (2013). Fundamentals of Machining Processes: Conventional and Nonconventional Processes, 2nd Edition. Boca Raton, Florida: CRC Press. El-Hofy, H. & Youssef, H. A. (2008). Machining Technology: Machine Tools and Operations. Boca Raton, Florida: CRC Press. Mcgoldrick, P. A. (2013). Advances in Manufacturing Technology: Proceedings of the First National Conference on Production Research. Boston, MA: Springer US. Pletcher, D. Industrial electrochemistry. London; New York: Chapman and Hall. Setchi, R., Howlett, R. J., Naim, M. & Seinz, H. (2014). Sustainable Design and Manufacturing 2014 Part 2. Lulu.com Singal, R. K., Mridul, S. & Rishi, S. (2008). Fundamentals of machining and machine tools. New Delhi: I.K. International Publishing House Pvt. Ltd. Trethewey, K. R., & Roberge, P. R. (2012). Modelling Aqueous Corrosion: From Individual Pits to System Management. Dordrecht: Springer Netherlands. The videos Basha, M. N. (2012, February 28Th). ElectroChemical Machining (ECM). [Video file]. Retrieved from Manufacturing IE-Purdue. (2015, April 13Th). How Electrochemical Machining Works. [Video file]. Retrieved from Read More