Investigations on weld metal chemistry and mechanical behaviour of bimetallic welds using CaO–CaF2–SiO2–Ni based electrode coatings
01 Apr 2019-Vol. 233, Iss: 4, pp 563-579
TL;DR: In this paper, an attempt has been made to design and develop an intermediate electrode based on CaO-CaF2-SiO2 ternary phase diagram system and nickel as an additional electrode coating ingred...
Abstract: The bimetallic welds between ferritic low alloy steels and austenitic stainless steels are widely used in the heat piping transport systems of nuclear power plants for connecting the heavy section low alloy steel components with those of high temperature stainless steel pipes. The operating experience of major nuclear power plant components has recently shown that bimetallic joints can jeopardize the plant availability and safety because of increased incidences of failure. In shielded metal arc welding process, the occurrence and severity of weld defects mainly depend upon the type of electrode filler wire and the electrode coating ingredients used. The use of nickel based filler metals is no longer considered as the final solution for unexpected failures of bimetallic welds due to incidences of hot cracking. In the present paper, an attempt has been made to design and develop an intermediate electrode based on CaO–CaF2–SiO2 ternary phase diagram system and nickel as an additional electrode coating ingred...
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TL;DR: In this paper, Ni-based shielded metal arc welding electrodes were used to join SS304L austenitic stainless steel to P91 martensitic steel used in power plant applications.
Abstract: This article is an attempt to develop Ni-based shielded metal arc welding electrodes to join SS304L austenitic stainless steel to P91 martensitic steel used in power plant applications. Nickel-base...
20 citations
TL;DR: In this article, physicochemical and thermo-physical properties of slags obtained from CaO-CaF2-SiO2-Al2O3 based shielded metal arc welding electrodes were investigated.
18 citations
TL;DR: In this article, the design and development of shielded metal arc welding (SMAW) electrode coating using extreme vertices design methodology has been discussed, where red ochre, a mineral waste from iron ore is added in the coating composition to study the effect of individual constituents and their interactions on the weld chemistry and microhardness.
Abstract:
Offshore structures in recent time are witnessing the increased application of dissimilar metal welds for enhanced structural integrity. Offshore structures are complex systems. Fabrication, maintenance, and repair of these structures require conventional and advanced welding technologies along with suitably chosen welding consumables. The present work aims at the design and development of shielded metal arc welding (SMAW) electrode coating using extreme vertices design methodology. This work also attempts to study weld metal chemistry along with microstructure and microhardness. Red ochre, a mineral waste from iron ore is added in the coating composition. Multi response optimization has been carried out to obtain optimum flux composition and to study the effect of individual constituents and their interactions on the weld chemistry and microhardness.
14 citations
TL;DR: In this article, the effect of industrial and laboratory prepared agglomerated submerged arc welding fluxes on the weldability, microstructural evolution as well as the structural integrity issues in API X70 line pipe steel welds was analyzed.
14 citations
TL;DR: In this article , the physicochemical and thermophysical properties of CaO-TiO2-SiO2−Na3AlF6 based electrode coating developed for the welding of advanced ultra-supercritical (AUSC) thermal power plant components were investigated.
13 citations
References
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"Investigations on weld metal chemis..." refers background in this paper
...This could be explained from the fact that Si4þ metallic cation from slag is reduced and increases the silicon content in the weld pool–slag interface during electrode positive polarity.(21) The accompanying reaction is shown:...
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