TY - JOUR
T1 - Model-based prediction of plasma resistance, and discharge voltage and current waveforms in micro-electrodischarge machining
AU - Mujumdar, Soham S.
AU - Curreli, Davide
AU - Kapoor, Shiv G.
AU - Ruzic, David
N1 - Publisher Copyright:
© 2016 by ASME.
PY - 2016/3/1
Y1 - 2016/3/1
N2 - In electrodischarge machining (EDM), the thermal energy causing material removal at the electrodes is given by the electrical energy supplied to the discharge. This electrical energy, also known as the discharge energy, can be obtained from time-transient voltage and current waveforms across the electrodes during a discharge. However, in micro- EDM, the interelectrode gaps are shorter causing the plasma resistance to be significantly smaller than other impedances in the circuit. As a result, the voltage and current waveforms obtained by a direct measurement may include voltage drop across the stray impedances in the circuit and may not accurately represent the exact voltage drop across micro-EDM plasma alone. Therefore, a model-based approach is presented in this paper to predict time-transient electrical characteristics of a micro-EDM discharge, such as plasma resistance, voltage, current, and discharge energy. A global modeling approach is employed to solve equations of mass and energy conservations, dynamics of the plasma growth, and the plasma current equation for obtaining a complete temporal description of the plasma during the discharge duration. The model is validated against singledischarge micro-EDM experiments and then used to study the effect of applied open gap voltage and interelectrode gap distance on the plasma resistance, voltage, current, and discharge energy. For open gap voltage in the range of 100-300 V and gap distance in the range of 0.5-6 μm, the model predicts the use of a higher open gap voltage and a higher gap distance to achieve a higher discharge energy. Copyright.
AB - In electrodischarge machining (EDM), the thermal energy causing material removal at the electrodes is given by the electrical energy supplied to the discharge. This electrical energy, also known as the discharge energy, can be obtained from time-transient voltage and current waveforms across the electrodes during a discharge. However, in micro- EDM, the interelectrode gaps are shorter causing the plasma resistance to be significantly smaller than other impedances in the circuit. As a result, the voltage and current waveforms obtained by a direct measurement may include voltage drop across the stray impedances in the circuit and may not accurately represent the exact voltage drop across micro-EDM plasma alone. Therefore, a model-based approach is presented in this paper to predict time-transient electrical characteristics of a micro-EDM discharge, such as plasma resistance, voltage, current, and discharge energy. A global modeling approach is employed to solve equations of mass and energy conservations, dynamics of the plasma growth, and the plasma current equation for obtaining a complete temporal description of the plasma during the discharge duration. The model is validated against singledischarge micro-EDM experiments and then used to study the effect of applied open gap voltage and interelectrode gap distance on the plasma resistance, voltage, current, and discharge energy. For open gap voltage in the range of 100-300 V and gap distance in the range of 0.5-6 μm, the model predicts the use of a higher open gap voltage and a higher gap distance to achieve a higher discharge energy. Copyright.
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U2 - 10.1115/1.4031773
DO - 10.1115/1.4031773
M3 - Article
AN - SCOPUS:85042392331
SN - 2166-0468
VL - 4
JO - Journal of Micro and Nano-Manufacturing
JF - Journal of Micro and Nano-Manufacturing
IS - 1
M1 - 011003
ER -