Future scope

water and urea mixed deionized water and unprocessed workpiece. There was 110 % enhancement in the corrosion resistance for the workpiece processed in hydrocarbon oil from that of the unprocessed workpiece.

8.1.4 Computation of alloyed layer thickness in electric discharge alloying by inverse estimation of energy distribution

An integrated FEM-ANN model has been successfully developed to accurately predict the alloyed layer thickness in electric discharge alloying of AISI P20 mold steel using powder metallurgy electrodes of titanium and aluminium at different processing conditions such as varying discharge current, pulse on-time, and various dielectric media.

The alloyed layer thickness was computed by considering the accurate values of fraction of energy distribution to the workpiece, FA. These values were computed by using the inverse estimation method and the ANN-based model. Following important conclusions were drawn from the study.

 The neural network of 3-10-1 architecture was found to be the optimum network.

 The developed methodology suggests that the fraction of energy FA varies from 0.129 to 0.215. This can be employed in the thermal analysis of the electric discharge-based manufacturing processes.

 The performance of the developed FEM-ANN was verified by carrying out the experiments. It was found acceptable with an average prediction deviation of 6.55 %.

 The present work facilitates a simple and quick methodology for accurate prediction of the alloyed layer thickness for complex manufacturing processes such as EDA.

This provides an efficient and economical alternative to the costly, tedious, and time- consuming experimental work.

of solid tool electrode, powder metallurgy electrode, and powder mixed dielectric can be carried out.

 Experimental and theoretical investigations onto the electro-thermal induced hydrodynamic melt flow in the electric discharge alloying process can be carried out.

The study can incorporate both the cathode and anode model during EDA. It is expected that the study can give a more realistic approach in computing the thickness of the alloyed layer formed.

 The limitations of the developed thermo-physical model lie in the fact that the developed model is for a single spark, and also, the effect of vaporization of the workpiece due to intense heating during the sparking phenomenon was not considered. Also, the heat capacity and the density are considered to be constant in the present study. These limitations can be an extension of the present work for developing a more realistic model.

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