Papers by Keyword: Activating Flux

Abstract: The article describes the results of experiments on the use of silicon production waste as an additive that improves the structure and properties of materials and the efficiency of welding process. The flotation technology can be used to separate gas cleaning dust, which is a silicon production waste product, into commercial products. The chamber product, containing ultrafine silica, was used as a modifying additive in concrete. It improved its structure and increased its strength compared to the samples without additives. The modifier made from chamber products introduced into gray cast iron made it possible to obtain graphite of a more favorable shape as compared to the lamellar form of graphite in traditional gray cast iron. Its strength increased. The experimental results on the welding process with an activating flux, which includes ultrafine silica isolated from the metallurgical waste, are presented. The activating flux improved the penetrating ability of the welding arc by 1.5-3 times, the energy consumption decreased by 30-50%.

Abstract: The objective of this study is to investigate the effects of activating fluxes on the weld bead geometry, hot cracking susceptibility and mechanical property of A356 and 6061 aluminum alloy dissimilar welds in the gas metal arc (GMA) welding process. In this activated GMA welding process, there were nine single-component fluxes used in the initial experiment to evaluate the penetration capability of butt-joint GMA welds. The grey relational analysis (GRA) was employed to obtain the better weld bead geometry of welds that were considered with multiple quality characteristics. Based on higher grey relational grade (GRG), four single-component fluxes were selected to create mixed-component flux in the next stage. The experimental results showed that the GMA welds coated with activating flux were provided with better geometry of dissimilar welds. The experimental procedure of activated GMA welding process not only produced a significant increase in tensile strength of welds, but also improved the hot cracking susceptibility of aluminum alloy welds.

Abstract: AC A-TIG welding on 5052 aluminum alloy was investigated. The single component of oxide TiO₂, SiO₂, Cr₂O₃, V₂O₅ and halide CaF₂ was served as activating fluxes to study the effect on weld penetration and weld forming. The experimental results show that weld penetration can be increased and welding productivity can be improved in A-TIG welding. Activating fluxes, especially TiO₂ and SiO₂, have more significant effect on weld penetration than conventional TIG welding, moreover the better weld shape formed after coating activating flux is obtained, weld width has slight decrease that makes HAZ of A-TIG welding smaller.

Abstract: Conversional TIG welding has low penetration and productivity. Recently, activating flux for TIG welding has received more and more attention. The paper has developed activating flux for TIG welding by means of orthogonal experience. The activating flux developed by orthogonal experience can penetrate austenite stainless steel butt plate in thickness of 8mm once and away which is three times the one of common TIG welding in the same welding parameter.

Abstract: The purpose of this work is to investigate the effects of activating flux on the penetration, depth-to-width ratio (DWR), angular distortion and hardness of Inconel 718 alloy and AISI 304 stainless steel (SS) dissimilar welds in the tungsten inert gas (TIG) welding process. In the activated TIG (A-TIG) process, the single component fluxes such as SiO₂, NiO, MoO₃ and MoS₂ and the mixed component fluxes that using 50 % of each single component flux to create six new mixtures were used in the experiment. The experimental results showed that the A-TIG welds coated with 100% SiO₂ flux was provided with best DWR of dissimilar welds. In addition, the experimental procedure of A-TIG welding process not only produced a significant increase in penetration and DWR of weld bead, but also improved the angular distortion and hardness of Inconel 718 alloy and AISI 304 SS dissimilar welds.

Abstract: The developing and application of activating flux which can dramatically increase the depth of weld bead penetration and improve the properties of weld bead using fusion welding process was summarized. The mechanisms of the activating flux increasing the depth of weld bead penetration especially the theories of arc constriction and the change of temperature gradient of surface tension were analyzed. The research work indicates that the activating flux will be used in more welding process to obtain deep weld penetration, high productivity, low deformation and excellent joint mechanical properties.

Abstract: The purpose of this work was to investigate the effect of activating fluxes and welding parameter to the penetration and depth-to-width ratio (DWR) of 6061 aluminum alloy welds. Bead-on-plate argon gas tungsten arc (GTA) welding process was made on 6061 aluminum alloy of plate without filling metals. The activating fluxes used in the experiment were CaO, ZnO, SiO₂, TiO₂, Al₂O₃, Cr₂O₃, CaF₂ and Na₂CO₃. Based on the higher penetration of weld bead and welding arc voltage, four fluxes were selected to create three new mixtures using 50% of each original fluxes. The mixed fluxes were used to investigate the effect to the welding penetration. Finally, The Taguchi method was employed to achieve optimal DWR of weld bead and investigate the welding parameters that significantly affect welding quality. The experimental procedure of GTA welding with activating flux via the Taguchi method produced full penetration of weld bead on a 6.35 mm thickness of 6061 aluminum alloy plate with single pass weld.

Abstract: FBTIG(Flux Bounded TIG)welding experiments for aluminum alloy were made using five species of single-component activating fluxes, including SiO₂、TiO₂、CaF₂、MgO, and NaCl, which was carried out to investigate the effects of flux gap and activating fluxes on weld formation. The mechanism of increasing welding penetration was analyzed linked with the change of arc shape in FBTIG. The experimental results indicate that five species of single-component activating fluxes can increase weld penetration obviously. Specifically, SiO₂ can increase weld penetration remarkably. When flux gap is 4mm, the D/W (depth/width) ratio of weld for FBTIG welding reaches 0.59. The significant increase of weld penetration is the result of comprehensive effect by arc contraction and reversal of the surface tension gradient in the liquid metal.

Abstract: In the present work, TIG and A-TIG welding were compared to show the arc constriction phenomena. A 2D axial symmetric model was developed to simulate the flow behavior in the melting pool. These results were compared to experiments carried out on a stainless steel disc (304L) melted by a stationary heat source. The influence of the Marangoni effect, arc constriction and type of flux is shown. The results point to the importance of the welding parameters and the use of a flux on the characteristics of the weld beads.

Abstract: The ATIG welding which is the high productivity version of conventional TIG welding, parallel with productivity increasing has some advantageous effect both on HAZ and weld joint grain structure. In this paper the effect of ATIG welding on austenite/ferrite ratio in duplex steel will be represented with experimental results performed on 8 mm thick 2205 type duplex steel. As collateral benefit through these results new evidences are originated to prove the “reversed Marangoni effect” theory.