Optimizing fusion zone grain size and hardness of pulsed current micro plasma arc welded Inconel625 sheets using Hooke and Jeeves Algorithm

Abstract

Purpose

The purpose of this paper is to optimize the fusion zone grain size and hardness using Hooke and Jeeves Algorithm.

Design/methodology/approach

Experiments are conducted as per four factors, five levels response surface method based central composite design matrix. Empirical relations for predicting grain size and harness are developed. The effect of welding variables on grain size and hardness are studies. Grain size and hardness are optimised using Hooke and Jeeves Algorithm.

Findings

The developed empirical relations can be effectively used to predict grain size and hardness values of micro plasma arc welded Inconel 625 sheets. The values of grain size and hardness obtained by Hooke and Jeeves Algorithm matches with experimental values with great accuracy.

Research limitations/implications

The developed mathematical models are valid for 0.25 mm thick Inconel 625 sheets only.

Practical implications

In the present paper only four important factors namely peak current, back current, pulse rate and pulse width are considered, however one may consider other parameters like plasma gas flow rate, shielding gas flow rate, etc.

Originality/value

The present work is very much useful to sheet metal industries manufacturing metal bellows, diaphragms, etc.

Citation

Siva Prasad, K., Srinivasa Rao, C. and Nageswara Rao, D. (2012), "Optimizing fusion zone grain size and hardness of pulsed current micro plasma arc welded Inconel625 sheets using Hooke and Jeeves Algorithm", Multidiscipline Modeling in Materials and Structures, Vol. 8 No. 3, pp. 338-354. https://doi.org/10.1108/15736101211269140