AMM MODEL TEST PAPERQ1.(a)State the characteristics and function of dielectric fluid used in EDM. In EDM, material removal mainly occurs due to thermal evaporation and melting. As thermalprocessingis requiredtobecarriedout inabsenceof oxygensothat the process canbecontrolled and oxidation avoided. Oxidation often leads to poor surface conductivity electrical!of the "or#piece hindering further machining. $ence, dielectric fluid should provide an oxygenfree machining environment. %urther it should have enough strong dielectric resistance so that itdoes not brea#do"n electrically too easily but at the same time ionise "hen electrons collide"ith its molecule. Moreover, during spar#ing it should be thermally resistant as "ell. bhat are the !arious "MS co#$onents to be inte%rated &hile i#$le#entin% "MS in anindustr'( Evolution of Manufacturing &ystems 'eneral %M& considerations, Manufacturing cells! &ystems (lanning (hysical planning, $umanresources, )uality* manufacturingdriving force, +ust,in,time manufacturing, 'roup technology, (rocessing an )uality Assurance Equipment -urning centers, Machining centers, .leaning and deburring equipment, .oordinate measuring machines!&ystem&upport EquipmentAutomatedmaterial movement andstoragesystems, .utting tools and tool management, /or#,holding consideration! %M& .omputer $ard"are, &oft"are, and .ommunication 0et"or#s &ystem hard"are and general functionality,%M& soft"are* structure, functions, and description!c! Describe the characteristics of tool in EDM.the basic characteristics of electrode materials are* 1 $igh electrical conductivity2electronsare coldemittedmore easily and there is less bul#electrical heating 1 $igh thermal conductivity 2 for the same heat load, the local temperature rise "ould be lessdue to faster heat conducted to the bul# of the tool and thus less tool "ear 1 $igher density 2 for the same heat load and same tool "ear by "eight there "ould be lessvolume removal or tool "ear and thus less dimensional loss or inaccuracy 1 $igh melting point 2 high melting point leads to less tool "ear due to less tool material meltingfor the same heat load 1 Easy manufacturability 1 .ost 2 cheapd!/hat is the effect of abrasive grain si3e on M44 in 5&M process6An increase in abrasive grain si3e results in higher M44 but poorer surface finish. MaximumM44 is achieved "hen abrasive grain si3e is comparable "ith amplitude of vibration of the tool.$ardness of the abrasives and method of introducing the slurry has also effect on M44.e!Explain in brief the principle of 5ltrasonic machining process6In ultrasonic machining, tool of desired shape vibrates at ultrasonic frequency78 to 9: #$3. !"ith an amplitude of 7:,:; Microns over "or# piece. 'enerally tool is pressed do"n "ith a feedforce%.