Abstract: This research aims to identify the optimal condition of the zinc Zamak3 alloys' melting process using 2k full factorial design and its optimizer in Minitab 18 software. The evaluation results of the ANOVA test with a first-order model revealed that the change in both independent variables simultaneously resulted in a statistically significant alteration of the percentage of slag. The independent parameters also had an effect individually on the response. Additionally, the slag percentage reduction was increased significantly due to an elevation of the temperature. However, the change of flux type resulted in an overall alteration of the slag percentage more than the change of melting temperature. The response optimizer demonstrated that the optimal condition was the melting temperature of 500°C coupled with the ZinCrex EP7119 flux achieving the lowest slag percentage of 1.672%, with the 95% confidence interval ranging from 0.643% to 2.701%.

Abstract: Basic oxygen furnace slag (BOF slag) contains high amount of useful oxides such as CaO, MgO, SiO₂, etc., therefore, a solution of the slag recycling would be used as a flux in pelletizing process. To understand role of slag in the pellet, this research examines the mechanical, chemical and microstructure properties of the pellets containing various amount of the slag. In the experimental process, the green pellets were made from a mixture of bentonite, iron ore and the slag. The green pellets were sintered in the resistance heating furnace maintaining temperature at 1200 °C for 120 minutes. Then the fired pellet was tested strength and observed microstructure with variation of the slag amount in the pellets. The result shown that cold compression strength of the pellets containing from 1.06 to 18.45 mass% slag was higher values than 200 kg/p, hence, the pellet was able to charge the pellets into the blast furnace. The highest strength was 342 kg/p with 5.08 mass% slag in the pellet. Besides, optical observed microstructure of the pellet indicated the phases of magnetite, hematite and silicate. In addition, the obtained results shown that there was a deterioration of porosity with increasing the slag amount. Accordingly, the porosity got a slight decrease when the slag amount increased from 1.06 to 5.08 mass% in the pellet. Once the amount of the slag was higher than 5.08 mass%, the porosity significantly reduced with increasing the slag amount; the porosity decreased from 23 to 12 %.

Abstract: High amount of basic oxygen furnace (BOF) slag in steelmaking process is a big challenge, therefore, recycling of the slag have been extensively concerned by not only steelmakers but also researchers. One of the promising methods is to use the slag as a flux in the pretreatment process because the basicity of slag is high and it contains high amount of MgO and CaO. This study examines recycling ability of the BOF slag as a part of the flux adding to the pretreatment process. In the experiment procedure, the flux was combination of the slag (59 mass%), CaO (32 mass%) and SiO₂ (9 mass%). The flux and the iron sample were put into the crucible, and then set up in the resistance furnace. The experiments were carried out at different temperatures of 1450, 1500 and 1550 °C with holding time of 15 minutes. The results shown that the S content in the iron significantly decreased in all cases of temperatures. S content in the iron in the pretreatment process reduced from the initial value to 0.007 mass% at the temperature of 1450 °C. However, at temperature of 1550 °C, the S content in the iron was 0.012 mass%. Besides, Si content in the iron reduced with increasing temperature; Si content in the iron significantly decreased from initial value of 2.67 mass% to 0.05 and 0.06 mass% once the temperatures were 1500 and 1550 °C, respectively. Additionally, it was indicated that Fe content in the slag after reaction dropped from the initial value of 6.20 mass% to 0.62 mass% at the temperature of 1550 °C.

Abstract: The paper investigates the technology of refining primary aluminum from vanadium impurities, based on flux treatment with boron-containing fluxes. In the Pavlodar region of the Republic of Kazakhstan, on the basis of local enterprises, the production of primary aluminum and products based on local raw materials is developing. The main problem in the production of primary aluminum on the basis of JSC “Kazakhstan Electrolysis Plant” is the presence of undesirable vanadium impurities, which pass into metal during electrolysis from baked anodes based on calcined coke (vanadium content up to 800 ppm) of the local enterprise LLP UPNK-PV (Pavlodar, Kazakhstan). The authors investigated the process of ladle refining of aluminum from vanadium using the Al-B (3% B) alloy. Laboratory and industrial tests have shown a decrease in the vanadium content by an average of 78% in the bulk of the metal, with an increase in its content in volume up to 5-10% of the ladle capacity. It was found that mixing leads to a certain averaging of the vanadium content in the ladle volume.

Abstract: The main trends in the use of silicate raw materials for the production of heat-insulating materials are considered. It is shown that the introduction of modifying additives-fluxes is promising to reduce the energy intensity of the technology. The substances that play the role of fluxes in the silicate industry are selected. The most active fluxes were chosen - sodium tetraborate Na₂B₄O₇ (borax) and sodium fluoride NaF. The mechanism of their melting effect on the silicate mass is investigated. It is shown that both borax and sodium fluoride are active fluxes, intensifying the melting of silicate raw materials of all types. The use of fluoride is hampered by a narrow temperature range, in which the formation of a stable porous structure is possible.

Abstract: The results of the development of the flux CaO-Li₂CO₃-B₂O₃, operating in the oxidizing environment of the furnace, are shown. Flux is used to protect the melt from oxidation and removal of oxides from the coated sample surface. The use of this flux in open furnaces made it possible to apply high-quality nickel coatings with a thickness of 18 μm, which is comparable to the thickness of coatings obtained in vacuum furnaces in argon atmosphere. The negative effect of flux components on the sample surface was noted during prolonged contact under the conditions of the oxidizing environment of the furnace. Practical application of the research results will provide high-quality diffusion coatings on metal products. In addition, economic efficiency is maintained through accessibility of the equipment and flux components.

Abstract: Manganese oxide and metallic manganese have made a long and varied contribution to the production of iron and steel through the centuries, long before Sir Robert Hadfield’s alloy manganese steel first produced in 1882. Although quite well known empirically, this contribution has sometimes been misunderstood or misrepresented.The success of some of the early so-called ‘natural steels’ was the presence of manganese oxides in the iron ores used.Manganese oxide was already used as a flux from the early days of the production of crucible steel in Asia and it now appears that it was used as a flux from the inception of the otherwise very different later European crucible steel technologies. After the introduction of crucible steel making in Britain in the 18^th century, foreign competitors believed that the reason for the success of the processes used at Sheffield was a secret flux and studies on recently discovered 18^th century crucibles in Sheffield have shown that process was indeed fluxed with manganese oxide.The function of manganese in the later European crucible steel industry has been rather overshadowed and confused historically by the very different ‘Carburet of manganese’, a strange concoction, patented by Josiah Heath in 1839 added to iron or steel to purify the metal. At the time the chemistry of the process was misunderstood and many acrimonious and inaccurate claims were made, crucially confusing the very different functions of manganese oxide and manganese metal, overshadowing the part already played by manganese oxide for almost a century previously..Finally manganese and its salts played a crucial role in the Bessemer process of steel making.

Abstract: The components of the flux are optimized and the environmental friendly flux withexcellent comprehensive performance is prepared. Then the composition of the solder paste isoptimized to prepare the SMT environmental protection and high efficient lead-free solder paste, andits performance is studied. The results show that the storage stability, printability, weldability andenvironmental protection of the SMT environmental protection and high efficient lead-free solderpaste are good, and the reliability is high. The related technical indexes have reached or superior tothe commercial solder paste, and have reached the commercial level initially.

Abstract: A technology of manufacturing surfacing with high-chromium special cast iron without heating is developed; the main directions for improving surfacing quality are outlined. It is proposed to replace manual arc welding with plasma surfacing using high-speed hard surfacing materials.

Abstract: Analysis of the TIG-welding impact on the structure and mechanical properties of pseudo-β titanium alloy VT19 welded joints, obtained with different welding speed, different filler wire amount in welded joint, with and without flux layer. Microstructure of obtained welded joints were investigated. Using welded joints microsections approximate amount of β-phase in different parts of welds have been obtained. Mechanical properties of the obtained welded joints were analyzed and dependency of tensile strength and amount of β-phase were build.