The Experts below are selected from a list of 129 Experts worldwide ranked by ideXlab platform
R.w. Messler - One of the best experts on this subject based on the ideXlab platform.
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Welding Type 347 stainless steel -- An interpretive report
1997Co-Authors: R.d. Thomas, R.w. MesslerAbstract:Stainless steels fall into three major classifications: ferritic, austenitic and martensitic. Type 347 stainless steels are classified as austenitic, though, as well be described later, they may contain small amounts of ferrite as well. They are of the 18-8 chromium-nickel Type with up to 1% niobium, an element once referred to as columbium. Type 347 stainless steel is the primary focus of this document. Similar stainless steels containing niobium will be included, such as Types 348 and 309Nb, as these are frequently encountered in certain applications in welded construction. Ferritic and duplex stainless steels, some of which may contain niobium, are not within the scope of this report. This report covers the following topics: applicable Welding processes; composition; properties; ferrite potential effect of weld thermal cycle; post-weld heat treatments; cracks and microfissures; and industrial applications.
Robert Ulewicz - One of the best experts on this subject based on the ideXlab platform.
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Analysis of the Welding Type and Filler Metal Influence on Performance of a Regenerated Gear
Materials, 2021Co-Authors: Svetislav Marković, Dušan Arsić, Ružica R. Nikolić, Vukić Lazić, Nada Ratković, Branislav Hadzima, Janusz Szmidla, Robert UlewiczAbstract:This paper presents the results of voluminous experimental investigations conducted to analyze the influence of the Welding procedure on the performance of regenerated gears. Cylindrical spur gears were tested, both newly manufactured and regenerated, in two fundamentally different ways: by hard facing (surfacing) with the “hard” filler metal (DUR 600-IG) and with the “soft” filler metal (EVB2CrMo) with subsequent cementation and quenching. The regeneration procedures were defined and executed, while, subsequently, the microstructure and microhardness of the hard-faced layers were established and measured, followed by checking the durability of the hard-faced teeth flanks. Finally, techno-economic analysis was performed to establish the rationality of the conducted regenerations, i.e., the costs of regenerated and newly manufactured teeth were compared. Based on the results of the conducted investigations, it was possible to establish the influence of the Welding Type on the performance characteristics (primarily the service life) of the regenerated gears. For individual reparatory hard facing, the procedure with the “hard” filler metal exhibited better characteristics, while for batch reparation of numerous damaged gears, the reparation with the “soft” filler metal, followed by cementation and heat treatment, might be more convenient.
R.d. Thomas - One of the best experts on this subject based on the ideXlab platform.
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Welding Type 347 stainless steel -- An interpretive report
1997Co-Authors: R.d. Thomas, R.w. MesslerAbstract:Stainless steels fall into three major classifications: ferritic, austenitic and martensitic. Type 347 stainless steels are classified as austenitic, though, as well be described later, they may contain small amounts of ferrite as well. They are of the 18-8 chromium-nickel Type with up to 1% niobium, an element once referred to as columbium. Type 347 stainless steel is the primary focus of this document. Similar stainless steels containing niobium will be included, such as Types 348 and 309Nb, as these are frequently encountered in certain applications in welded construction. Ferritic and duplex stainless steels, some of which may contain niobium, are not within the scope of this report. This report covers the following topics: applicable Welding processes; composition; properties; ferrite potential effect of weld thermal cycle; post-weld heat treatments; cracks and microfissures; and industrial applications.
Il Sohn - One of the best experts on this subject based on the ideXlab platform.
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Effect of MnO to hydrogen dissolution in CaF2–CaO–SiO2 based Welding Type fluxes
Science and Technology of Welding and Joining, 2012Co-Authors: Jun Yong Park, W-s Chang, Il SohnAbstract:The effect of MnO on the hydrogen solubility in the CaF2–CaO–SiO2 based Welding flux system at 1823 K has been studied. At an acidic slag composition of CaO/SiO2 molar ratio or basicity of 0·8 and below, MnO addition decreased the hydrogen solubility. At an intermediate slag composition of CaO/SiO2 molar ratios of 1·1 and 1·3, the hydrogen solubility as a function of MnO additions resulted in a parabolic behaviour showing a minimum and then increasing with higher MnO content. MnO was found to behave as a basic oxide, which decreases the hydrogen solubility when the incorporation hydroxyl mechanism is dominant for an acidic slag and increases the hydrogen solubility when the free hydroxyl mechanism is dominant for a basic slag. This change in the dominant hydrogen dissolution mechanism was also apparent from the hydrogen solubility results at various CaO/SiO2 molar ratios and fixed MnO contents. A higher hydrogen solubility in the slag is likely to lower the diffusible hydrogen content in the weld metal, a...
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Hydrogen Dissolution in the TiO2–SiO2–FeO and TiO2–SiO2–MnO Based Welding-Type Fluxes
ISIJ International, 2011Co-Authors: Jun Yong Park, Jin Gyun Park, Changhee Lee, Il SohnAbstract:The hydrogen solubility of TiO2–SiO2–FeO and the TiO2–SiO2–MnO Welding-Type flux systems have been studied to identify and compare the hydrogen dissolution behavior in molten Welding fluxes at high temperatures of 1823 K in a wide range of compositions. The dependence of the water vapor pressure and the hydrogen solubility showed a slope of 1/2 suggesting thermodynamic equilibrium was obtained. For an acidic slag composition, the hydrogen was found to be incorporated within the silicate network structure and decreased with higher TiO2 additions due to the dilution effect of SiO2 and subsequent decrease in incorporation sites. The additions of FeO and MnO, which acts as a basic component to the slag system, provided free oxygen ions, and decreased the incorporation sites for hydrogen dissolution. FTIR analysis of as quenched molten flux samples showed more pronounced bands for Si–OH bending vibrations when hydrogen solubility increased. For a basic slag composition, the hydrogen existed as a free hydroxyl and the addition of basic components such as FeO and MnO to the slag system increased the hydrogen solubility in the molten slag. Furthermore, it was observed that the hydrogen solubility was slightly lower for FeO than MnO containing fluxes.
Svetislav Marković - One of the best experts on this subject based on the ideXlab platform.
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Analysis of the Welding Type and Filler Metal Influence on Performance of a Regenerated Gear
Materials, 2021Co-Authors: Svetislav Marković, Dušan Arsić, Ružica R. Nikolić, Vukić Lazić, Nada Ratković, Branislav Hadzima, Janusz Szmidla, Robert UlewiczAbstract:This paper presents the results of voluminous experimental investigations conducted to analyze the influence of the Welding procedure on the performance of regenerated gears. Cylindrical spur gears were tested, both newly manufactured and regenerated, in two fundamentally different ways: by hard facing (surfacing) with the “hard” filler metal (DUR 600-IG) and with the “soft” filler metal (EVB2CrMo) with subsequent cementation and quenching. The regeneration procedures were defined and executed, while, subsequently, the microstructure and microhardness of the hard-faced layers were established and measured, followed by checking the durability of the hard-faced teeth flanks. Finally, techno-economic analysis was performed to establish the rationality of the conducted regenerations, i.e., the costs of regenerated and newly manufactured teeth were compared. Based on the results of the conducted investigations, it was possible to establish the influence of the Welding Type on the performance characteristics (primarily the service life) of the regenerated gears. For individual reparatory hard facing, the procedure with the “hard” filler metal exhibited better characteristics, while for batch reparation of numerous damaged gears, the reparation with the “soft” filler metal, followed by cementation and heat treatment, might be more convenient.