Investigation on flux design & their effect on the mechanical properties of the SAW of Duplex Stainless Steel-2205

Abstract The SAW fluxes for Duplex Stainless Steel (DSS)-2205 are not easily available. Generally, the available flux configuration is suitable for different grades of stainless steel but not suitable for the DSS. The current research aims to formulate the flux for DSS-2205 by varying the different flux ingredients and to investigate the impact of linear flux ingredients and their binary mixture effect on the mechanical characteristics of the butt joining of DSS-2205. The technique of extreme vertices design suggested by McLean and Anderson is employed to develop twenty-one fluxes. The effect of twenty-one flux ingredients was analyzed on the fabricated weldment’s characteristics such as ultimate tensile strength (UTS), percentage elongation, impact strength, and microhardness. In this research, a mathematical model has been developed for UTS, percentage elongation, impact strength and microhardness of weld specimens in terms of the flux ingredients. It is found from the experiments that the tensile strength and percentage elongation of weldments is increased by the flux ingredients such as silica (SiO 2 ) and magnesium-oxide (MgO), while the alumina (Al 2 O 3 ) and calcium fluoride (CaF 2 ) has decreasing effect on UTS. Impact strength is found to be decreased by the linear effect of Al 2 O 3 . Excluding CaF 2 , all the linear flux ingredients have an increasing effect on the microhardness of the weld metal. Increased binary effect of Al 2 O 3 .CaF 2 , Al 2 O 3 .MgO, and MgO.CaF 2 flux ingredients are found on the UTS, percentage elongation, impact strength and microhardness of the weldment. For the adequacy of the developed regression model, analysis of variance (F-statistics) is used for all the regression equations.