Machining takes place due to anodic dissolution at atomic level of the work material due to electrochemical reaction. A schematic of chemical machining process is shown in figure 6. Materials removed from the workpiece stay in the electrolyte fluid. Within a limited time of 10 hours, this course would elaborate on the theory of metal cutting supplemented with numerical problems. Advantages and disadvantages of chemical machining.
Nptel mechanical engineering video lecture online study. Electrochemical machining works on the faraday law of electrolysis which state that if two electrode are placed in a container which is filled with a conductive liquid or electrolyte and high ampere dc voltage applied across them, metal can be depleted form the anode positive terminal and plated on the cathode negative terminal. Introduction to nontraditional machining iit kanpur. On this channel you can get education and knowledge for general issues and topics. Electrochemical machining ecm is a nontraditional machining process uses the principle of faraday to remove metal from the workpiece. Electrochemical grinding is a process that removes electrically conductive material by grinding with a negatively charged abrasive grinding wheel, an electrolyte fluid, and a positively charged workpiece. Electrochemical machining, electroplating or electro discharge machining are the examples work on this principle. What is hybrid manufacturing and classification of hybrid machining process technological improvement of machining processes can be achieved by combining different machining actions or phases to be used on the material being removed.
Chemical machining for some special purposes can also be achieved by using a jet of reactive gas, e. Working principle of chm the main working principle of. Masking tape can be used to protect areas not to be removed. Metal casting is a labour intensive process automation. It is also known as contactless electrochemical forming process. Electrochemical machining is a process of a selective dissolution of the anodically connected work piece material submerged in an electrolyte together with an anodically connected tool. Other articles where chemical machining is discussed. Laser beam machining lbm is a non conventional machining manufacturing process, a form of machining, in which a laser is directed towards the work piece for machining. What is electro chemical machining process engineers academy duration. Introduction electrochemical machining ecm is one of the newest and most useful nontraditional machining ntm process belonging to electrochemical category. The part of the workpiece whose material is to be removed, is brought into the contact of chemical called enchant. In cm material is removed from selected areas of workpiece by immersing it in a chemical reagents or etchants. This is known as gaseous chemical machining or hot chlorine machining and can be. A mechanical conventional single cutting or ma action process can be combined with the respective machining phases of electrodischarge.
Traditional machining methods are often ineffective in machining hard materials like ceramics and composites or machining under very tight tolerances as in micromachined components. Electrochemical machining ecm is a machining process in which electrochemical process is used to remove materials from the workpiece. To accomplish the aforesaid objectives one should first know why and how the cutting tools fail. The process of metal removal by electro chemical dissolution was known as long back as 1780 ad but it is only over the last couple of decades that this method has been used to advantage. The metal is removed by the chemical attack of enchant. Photochemical machining pcm, also known as photochemical milling or photo etching, is a chemical milling process used to fabricate sheet metal components using a photoresist and etchants to corrosively machine away selected areas. What is hybrid manufacturing and classification of hybrid. Paul,department of mechanical engineering, iit kharagpur. Tool geometry, chip formation, cutting force calculations and measurement, tool wear and other aspects will be given due attention. Chemical machining, copper alloy, chemical etchant, depth of etch, surface roughness corresponding author, phone. Soil exploration lecture notes, notes, pdf free download, engineering notes, university notes, best pdf notes, semester, sem, year, for all, study material. The technique is broadly applied to machine geometrically. Nptel provides elearning through online web and video courses various streams. Advanced machining processes video course mechanical.
This is known as gaseous chemical machining or hot chlorine machining and can be used for deburring of metal parts. Machining a shearing process in which excess materials is removed by cutting tools. These methods form a group of processes which removes excess material by various techniques involving mechanical, thermal, electrical chemical energy or combination of these energies. The method is related to the process used for making metal printing and engraving plates.
This process uses thermal energy to remove material from metallic or nonmetallic surfaces. Nptel video lectures, iit video lectures online, nptel youtube lectures, free video lectures, nptel online courses, youtube iit videos nptel courses. Water jet and abrasive water jet machining youtube. Nptel syllabus process modelling and simulation web course course outline the process modeling and simulation of chemical engineering processes has attracted the attention of scientists and engineers for many decades and is still a subject of major importance for the knowledge of unitary processes of transport and kinetics. This group includes chemical milling, photochemical machining, and thermo chemical machining. A variety of work materials repeatable regular geometries close tolerance ump syllabus question bank lecture notes syllabus part a 2 marks with answers part b 16 marks question bank with answer, all the materials are listed below for the students to make use of it and score good maximum marks with our study. The two electrodes workpiece and tool is immersed in an electrolyte such as nacl.
Electrochemical machining ecm is used to remove metal and alloys which are. These methods form a group of processes which removes excess material by various. Nptel chemical engineering video lecture online study material. Chemical machining 632014 hareesha n g, dept of aero engg, dsce 2 3.
Advantages and disadvantages of chemical machining advantages induces no stress or cold working in the workpiece can be applied to large areas can be etched simultaneously virtually unlimited shapes possible to make thin sections and very disadvantages requires the handling of disposal of potentially material removal rate is. Working principle of chm the main working principle of chemical machining is chemical etching. Principles of ecmequipmentssurface roughness and mrrelectrical circuit. Photochemical machining pcm, also known pdf viewer for android tab as photochemical milling or photo etching, is the process of fabricating sheet metal components. Principally electrochemical machining is similar to electropolishing where the work piece surface roughness decreases due to the conversion of the atoms into ions and their removal from the. Module 3 selection of manufacturing processes nptel. The method of making contact of metal with the enchant is masking. Electrolysis is based on faraday laws of electrolysis which is stated as. Chemical machining is oldest of nontraditional machining processes employed as micromachining process to produce micronsize components. Modern machining methods are also named as nonconventional machining methods.
Material removal processes machining is the broad term used to describe removal of material from a workpiece includes cutting, abrasive processes grinding, advanced machining processes electrical, chemical, thermal, hydrodynamic, lasers automation began when lathes were introduced in 1700s. Module 3 selection of manufacturing processes lecture 6 design for powder metallurgy instructional objectives by the end of this lecture, the student will learn the basic principles of powder metallurgy processes and the critical issues to be considered during design of parts to be manufactured using powder metallurgy processes. The chemical machining processes include those wherein material removal is accomplished by a chemical reaction, sometimes assisted by electrical or thermal energy applications. Part 3 elaborates chemical and electrochemical machining processes. Photochemical machining suron precision technology. In the process, workpiece is taken as anode and tool is taken as cathode. Introduction to mechanical micro machining usb media storage type. This course would encompass a comprehensive study of metal cutting and machine tools. Kinematics of machines nptel online videos, courses. The high frequency of monochromatic light will fall on the surface then heating, melting and vaporizing of the. This process emerged in the 1960s as an offshoot of the printed circuit board industry. This nonelectrical process removes metal from selected or overall areas by controlled chemical action. Chemical machining also known as photo chemical machining or pcm, photofabrication, or photo chemical milling is a process through which decorative metal items and precision metal parts are formed photo chemical machining is often used in the production of. Chemical machining cm is the controlled dissolution of workpiece material etching by means of a strong chemical reagent etchant.
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