Abstract—Non-Conventional methods are widely used due to their time saving process with superior quality. In non-conventional machining process we use thermal energy provided by a heat source, to melts and (or) vaporizes the volume of the material to be removed. Among thermal removal methods, Electric discharge machining is most widely used method for making tools such as Die steel, tool steel which are difficult to machine by simple methods. It was found that considerable research has been done on various aspects of electrical discharge machining of low carbon steels, carbides and a few die steels such as AISI D2, H13, haste alloy etc. steel, with different types of electrodes such as ZrB2-Cu, Cu, CuW etc. but sufficient data has not available on H-11 steel. H-11 is a Die tool steel. H-11 offers high corrosion resistance, wear strength and high hardness. It is widely used in extrusion tools, forging dies, stamping dies, etc. Hence there is a need to investigate the machining of this material with copper and copper tungsten (CuW) electrodes (made through powder metallurgy technique). A L18 Taguchi’s standard orthogonal array is used for experimental design by varying different input machining parameters such as discharge current, gap voltage, duty cycle, polarity, retract distance and their effect on Material Removal Rate ( MRR). It was found that Material Removal Rate is maximum with conventional copper electrode with peek current (14A) at voltage (40V) and duty cycle (0.92) in Positive polarity.

Index Terms—Electrical Discharge Machining (EDM), Powder Metallurgy (PM) Taguchi method, Material Removal Rate (MRR)

Cite: Sumesh Kapila and Dinesh Kumar, "Study of Material Removal Rate of H11 Die Tool Steel during Electric Discharge Machining at Normal Polarity," International Journal of Mechanical Engineering and Robotics Research, Vol. 3, No. 3, pp. 405-415, July 2014.