Metallurgical Characterization of Buttering Deposits

Authors:

Dinesh Rathod (Manav Rachna International University, Faridabad)

Abstract:

The dissimilar metallic joints play a critical and indispensable role in the primary heat transport piping system of nuclear reactors. For economic reason primary pressure vessels are made up of SA508 Cl.3 and transport pipelines are made up of SS304LN. Carbon migration is one of the major problems in the welding of these dissimilar joints. For preventing the carbon migration, use of nickel base metals such as Inconel are suggested for buttering and welding. In the present study, focus was given on identification of carbon migration. Considering the carbon percentage in the Low Alloy Steel, Mild steel with same carbon composition was selected for study and the data will be applied to the Low Alloy Steel and SS304LN welding. The buttering layers were made with Inconel 182 and Ni+Fe alloy using SMAW and GTAW process to establish optimum buttering thickness and optimum number of buttering layers as well.

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