Characterisation of Mechanical Properties of Multipass Submerged Arc Weld by Model Analysis of Its Microstructure Facilitated by AID of Computer

Abstract

An analytical model for quantitative analysis of microstructural constituents of a multipass weld produced by consumable electrode process, such as the fraction of dendritic and reheat refined zones in the matrix, has been proposed. The universality of the proposed model has been justified by Its applicability for a multipass weld deposit of any material, with due consideration of its physical properties relevant to the operation of the model expressions at appropriate steps of analysis. Empirical correlations of some mechanical properties of multipass weld of C-Mn steel with its dendrite content have been developed by preparing a data bank on the reported results. On the basis of the mathematical model expressions and the empirical relationships, a user's friendly PC based software has been developed using C language to estimate the microstructural constituents of a multipass weld prepared at given welding parameters and its mechanical properties. The database of the empirical relationship for prediction of mechanical properties of a multipass weld has been kept flexible for updating by incorporation of new data in it. The validity of estimated characteristics of a multipass submerged arc weld of C-UIn steel, such as its bead geometry, morphology, and mechanical properties, deposited at different welding parameters has been verified with a number of experimental data reported by earlier workers as well as with those produced in this work. The ready usage of the model expressions for analysis of the weld characteristics using the welding parameters reported by various workers shows the versatility of the proposed analytical model and the software.