Pdf the electroslag remelting process esr is important because it provides better control of the solidification. After passing through the flux, the alloy slowly cools down and solidifies again into a remelted ingot 1, 2, 3,4,5. Us6350293b1 bottom pour electroslag refining systems and. Esr refining potential for titanium alloys using a caf2. In the first part the heat necessary to melt an electrode with a flat tip shape is calculated. In the refining process, a slag or flux is used both as a heat source and as a refining medium.
Jul 22, 1975 the present invention relates generally to an electroslag refining process for uranium and uranium alloys, and more particularly to such a process where scrap material is refined in such a manner that the oxygen content therein is reduced to less than about 100 parts per million ppm. Report of the committee on electroslag remelting and plasma. The electroslag melting process page 12 unt digital. The ingots are used for manufacturing heavy parts for electric power generating units turbine shafts, generator rotor shafts. The current running through the slag via the electrode heats up the slag due to its high electric resistance to the point that the tip of the electrode, which is immersed in the slag, is liquefied. Nov 26, 2015 electroslag welding is capable of welding plates with thicknesses ranging from 50 mm to more than 900 mm and welding is done in one pass. Metallurgy of the electroslag remelting process due to the superheated slag that is continuously in touch with the electrode tip, a liquid film of metal forms at the electrode tip. Process for electroslag refining of uranium and uranium. Flux for electroslag welding sandvik 37s se811 81 sandviken sweden march 2005 general description sandvik 37s is a highly basic, agglomerated flux for electroslag strip surfacing.
Using of electroslag technology for refining of titanium and alloys on its base from nitrogenrich inclusions. A method for a routine, direct analysis for fluoride in electroslag refining esr fluxes, using potentiometry, is described that is faster, more economical, and less operatordependent than previously known methods of fluoride analysis in these materials. Esr electroslag remelting is the abbreviated name given to electroslag consumable electrode remelting and secondary refining process. Unit for electroslag remelting of metals and alloys with high reaction ability under active metalcontaining fluxes in controlled atmosphere or vacuum. Prior to welding the gap between the two work pieces is filled with a welding flux. On melting of electrodes during electroslag remelting. Control of hydrogen during esr process sciencedirect. The droplets enters the molten steel pool, bottom of which is progressively solidifying. In an earlier work, an ultrahigh strength steel, designated as 03ccrmov esr 03c10mo03v, which is a modified version of afnor 15cdv6 steel, has been developed by increasing carbon content from 015 to 028% and by processing the steel through electroslag refining esr with inoculation by either niobium or zirconium during esr. In electroslag refining the slag normally provides a cover for the molten metal or alloy pool and eliminates the costly vacuum systems that are required for vacuumarc melting. Electroslag remelting an electrometallurgical process in which a metal in the form of a consumable electrode is remelted in a bath of an electrically conducting synthetic slag by the action of heat released upon the passage of electric current through the slag.
Electroslag melting is also known as electroflux melting is a process of melting and refining steel and super alloys for mission critical application. Influence of oxygen addition on structure and properties of. Ingots up to 200 metric tons are produced by electroslag remelting utilizing simultaneous remelting of tens of electrodes. This bulletin traces the development of the electroslag melting process from its modest beginnings to the present. The task of producing highquality large ingots from highalloy steels and alloys has not as yet been completely fulfilled.
Experimental results indicate that the iron content decreases with increasing na 2 b 4 o 7 addition and remelting time, and the iron content decreases from 0. Test methods for electroslag remelting furnaces are specified in iec 60779. Electroslag remelting for the production of tool steels. Based on more than forty years of experience with both processes, deutsche edelstahlwerke have excellent knowhow and process engineering in place, which is optimally adapted to meet their customers requirements. Table 1 depicts the histori cal development of the process. Journal of minerals and materials characterization and engineering, 2017, 5, 385407. It is also found that the ductility, impact toughness and. This report is based upon the electroslag refining esr operations undertaken by the commonwealth steel company, waratah, nsw, and draws upon detailed technical records of both production and experimental operations over an extended period. An electroslag refining starter includes a refined disk fixedly joined in a central aperture of a mounting ring.
The technology of electroslag remelting esr meets these demands. Rezaei3 1 institute of advanced technologies for metallic materials, tarbiat modares university, tehran, iran. Drops of the molten electrode metal pass through the slag layer to form a layer of metal underneath. Since the usa patent of electroslag remelting esr metallurgy was held by p. Although electroslag welding is mainly used for the joining of mild and lowalloy steels, satisfactory welds have been made in highalloy steels, titanium and aluminium. Flux samples were prepared using a rapid sodium carbonateborate fusion with subsequent digestion in dilute nitric acid prior to chelant.
Electroslag welding esw is a highly productive, single pass welding process for thick greater than 25 mm up to about 300 mm materials in a vertical or close to vertical position. Review on desulfurization in electroslag remelting esr. The objectives of the research reported herein include 1 testing the feasibility of preparing very lowsulfur steels electroslag and electricarcfurnace processes, 2 evaluating the possibility of eliminating an external desulfurization step in the electricarcfurnace process to produce such steels, 3. Determination of total fluoride content in electroslag. The electroslag refining esr process is one of the most important secondary refining processes owing to its relatively low production cost, low capital investment and ability to produce high quality steel with desired chemistry and homogenous structure. It is also used to describe three separate processes, using the principle of electroslag namely i consumable electrode metal refining and cost structure improvement process ii the semicontinuous or 11.
The process is intoated by that up the bux forms the slag. Effect of inoculation during electroslag refining on grain. A method of forming an ingot of refined metal by the electroslag refining process comprises the steps of introducing into the lower open end of a cooled mould a solid uncooled electricallyconductive member of a material weldably compatible with the metal to be refined, the member having a surface area sufficient to conduct the full working current employed in the process. Electroslag welding was derived from a metal manufacturing process called electroslag remelting or refining esr. Fluoride containing slag, which influences the nonmetallic inclusions to a great extent, has been widely used for the electroslag remelting process. The influence of esr on improvement in service properties of 20hgs2h steel, in remelting for refining, naukova dumka, kiev, pp. Electroslag remelting article about electroslag remelting. Electroslag remelting furnaces for more information visit. Effect of electroslag refining on microstructure and. The electro slag refining process esr is a variant of the group of consumable electrode remelting processes esr, var, ebr and par. The current work is devoted to the investigation of oxygen impact on the structure and properties of titanium. Electroslag refining 10 is a secondary refining process already well established for ferrous materials. However, since uranium is a very active and highly toxic metal, electroslag melting must be conducted in a closed system with a protective environment of an inert gas. For this purpose, oxygen was introduced into titanium during chamber electroslag remelting by three different methods.
An electric arc is initially struck by wire that is fed. The electroslag remelting esr process is used to remelt and refine steels and various super. This simplification stems mainly from the use of a wire guide. Figure 1 shows a schematic diagram of the esr process that uses a stationary. This can be attributed to the better conditions which exist for refi ning in the specially chosen slag and for the crystallization of the metal in the case of esr. Esw is similar to electrogas welding, but the main difference is the arc starts in a different location. Electroslag remelting esr, also known as electroflux remelting, is a process of remelting and refining steel and other alloys for missioncritical applications in. Investigation on the effect of electrode tip on formation of metal. Designs and manufactures furnace systems for a variety of metallurgical processes, including. A bottom pour electroslag refining system refines raw material into refined liquid metal.
As the developing droplets pass through the slag, the metal is cleaned of nonmetallic impurities which are removed by chemical reaction with the slag or by physical. Evaluation of the electroslag remelting process in medical. Despite it is one of the most abundant elements in the earths crust, it is. Effect of electroslag refining on the fracture toughness and.
If you need to print pages from this book, we recommend downloading it as a pdf. It principle is based on the electroslag welding process. Printed m gri britain effect of electroslag refining on the fracture toughness and fatigue crack propagation rates in heat treated aisi 4340 steel mohan g. The gestation period was long and torturous going from principles written down in 1892 to actual research in 1935 to full. Iron reduction in aluminum by electroslag refining. May 14, 2014 many factors influence the nonmetallic inclusions in electroslag steel including furnace atmosphere and inclusions content in the consumable electrode, slag amount and its composition, power input, melting rate, filling ratio, and so on. State key laboratory of advanced metallurgy, university of science and technology beijing, beijing 83, china. Strip cladding has been around for decades, and historically, submerged arc strip cladding sasc has been the most commonly used process, offering deposition rates of about 33 pounds per hour. Barrancos mooney pdf cladding electroslga typically a very continuous operation that requires high amperages and high duty cycles. Factors influencing power consumption and powersaving measures. Influence of oxygen addition on structure and properties. Another timesaving benefit of the essc process stems from the electroslag refining that occurs when the molten metal passes through the slag bath. The steel dripping from the electrode is then freed from contamination.
Electroslag cladding provides alternative to standard cladding techniques. During electroslag remelting, the temperature of the slag, which consists of various components caf 2, cao, sio 2, al 2 o 3, and others, exceeds 2500c. Coldstarting techniques for use with the experimental electroslag refining furnace at mrl have been examined. The electroslag melting process page 214 digital library. Dec 12, 2014 single or multiple solid as well as fluxcored electrodes may be used. The electroslag refining experiments were carried out using kclnaclna 3 alf 6 slag. Esr is a continuous process, where during the remelting of the consumable electrode, refining and solidification of the steel occur simultaneously.
Initial trials have demonstrated the viability of electroslag crucible melting for producing cast alloys with low impurity content and superior tensile properties. It was found that the removal efficiency of electroslag refining for. Download fulltext pdf electroslag refining of crnimowmnv ultrahighstrength steel article pdf available in journal of minerals and materials characterization and engineering 0506. Removal of nonmetallic inclusions from aluminum by electroslag.
Us3389208a us63611767a us3389208a us 3389208 a us3389208 a us 3389208a us 63611767 a us63611767 a us 63611767a us 3389208 a us3389208 a us 3389208a authority us. Consumableguide welding is a much simplified version of electroslag welding. Titanium production by magnesium thermal reduction in the. Electroslag welding an overview sciencedirect topics. Prasad department of metallurgy, indian institute of science, bangalore 560012, india abstracthe aisi 4340 steel has been. The electroslag remelting esr process is a foundry method to refine and mold molten metals based. The molten droplets formed at the tip of the electrode fall through the molten slag, and collect in a pool on the baseplate to solidify.
Us3389208a consumable electrode furnace for electroslag. Electro slag remelting esr ald vacuum technologies. The effect of electroslag refining on iron reduction from commercial aluminum was investigated. It dispenses completely with the rising and gating. The disk is consumed during starting and is replaceable in the same mounting ring for subsequent reuse. It gives excellent slag removal and bead appearance also for nballoyed strip electrodes. Problems of special electrometallurgy, 3, 2002, 10. The mounting ring supports the starter in a crucible below an ingot being electroslag refined. Electroslag remelting esr, also known as electroflux remelting, is a process of remelting and refining steel and other alloys for missioncritical applications in aircraft, thermal power stations, nuclear power plants, military technology, etc the electroslag remelting esr process is used to remelt and refine steels and various superalloys, resulting in highquality ingots. Effect of slag on inclusions during electroslag remelting.
Electroslag remelting esr, also known as electroflux remelting, is a process of remelting and refining steel and other alloys for missioncritical applications in aircraft, thermal power stations, nuclear power plants, military technology, etc. Two coldstarting devices based on exothermic reactions and resistanceheating, respectively, have both been developed to the stage where reliable starting can be achieved. Electroslag welding is a process providing one of the highest weld deposition rates and is therefore most costeffective for suitable applications its unique capability permits to weld in one pass groove joint of two plates, thick 1 to 12 inches 25 to 300 mm and more. Pdf electroslag refining of crnimowmnv ultrahighstrength steel. Electroslag welding is a process providing one of the highest weld deposition rates and is therefore most costeffective for suitable applications its unique capability permits to weld in one pass groove joint of two plates, thick 1 to 12 inches 25 to 300 mm. In the electroslag refining process, an electricallyconductive slag within a mould is maintained in a molten state and at a temperature above the melting point of the metal to be refined. Introduction this process was developed originally in the erstwhile ussr in 1930. Applies to electroheat installations for remelting and, in some cases, for refining processes of metals through direct resistance heating of a conductive slag. Electroslag welding a gocess ft19co of meta as as filler metal is achieved from heat 9ervaed the resgance of mciten slag, weld pod shielded motten wt. Unrefined metal is introduced into the mould and is refined as it passes in.
Cast electrodes of commercial aluminum were electroslag refined using kclnaclna 3 alf 6 slag containing na 2 b 4 o 7. The electroslag melting process page 214 unt digital. Computational modeling of the electroslag remelting esr. Electroslag refining of crnimowmnv ultrahighstrength steel. Unfortunately, this book cant be printed from the openbook. The molten steel in form of both liquid film on the electrode tip and descending droplets contacts with the slag and get refined due to desulfurization and removal of nonmetallic inclusions sulfides and oxides. The electroslag crucible melting process, developed on the well established principles of electroslag refining, has been used to cast age hardening cu05cr alloys using copper scrap. Effects of electroslag refining on removal of iron impurity and alumina inclusions from aluminum were studied on a laboratoryscale apparatus. Unlimited viewing of the articlechapter pdf and any associated supplements and figures. Electroslag melting experience for reactive metals, base. Electroslagwelding, cost effective vertical one pass. With every increase of the requirements of the users and the properties of thick plates and forgings and the appropriate increase of the complexity of the alloying systems of steel and alloys this problem becomes more acute, in particular in the production of certain. Electro slag remelting esr is a process used for remelting and refining of steels and special alloys which are used for critical applications in aircraft, thermal and nuclear power plants, defense hardware, etc. Since the choice of flux is a unique parameter in the electroslag process, two chapters are developed to this subject.
The current required is about 600 a at 40 to 50 volts although higher currents are used for thick plates. An introduction to premium melting carpenter technology. Electroslagwelding, cost effective vertical one pass process. Dmitri kopeliovich electroslag welding is a welding process, in which the heat is generated by an electric current passing between the consumable electrode filler metal and the work piece through a molten slag covering the weld surface. Electroslag technology of production of large forging. Refining usually results in the elimination of a number of casting or solidification defects, such as shrinkage porosity, gas porosity, pipe, micro and macro segregation. Equipment used for electroslag welding operations electroslag welding is capable of welding plates with thicknesses ranging from 50 mm to more than 900 mm and welding is done in one pass. Evaluation of the electroslag remelting process in medical grade of 316lc stainless steel s. The bottom pour electroslag refining system comprises an electroslag refining crucible. Nov 26, 2019 titanium is widely used in specific applications due to its high strength, low density and good chemical stability. Important basic mechanisms such as electrochemistry, thermochemistry, and heat transport are described. The electroslag refining technique is one of the modern tools which is capable of imparting superior mechanical and chemical properties to metals and alloys. The method, which significantly increases the quality of the metals and alloys produced, was. Flux 37s is used together with strip electrodes of the cr.
Consumable electrode furnace for electroslag refining download pdf info publication number us3389208a. Electroslag remelting furnaces in the 1960s consarcs engineers conceived a new approach to electroslag remelting, quite different from others in use at the time. Esr refining potential for titanium alloys using a caf 2. Mar 11, 1975 this invention relates to the electroslag refining process and to apparatus for use therewith.
The present work examines a new method of introducing inoculant during esr, resulting in higher recovery of the inoculant. The watercooled copper mold provides relatively high gradient of temperature resulting in. Electroslag crucible melting of age hardening copper. The resulting improvements in the efficiency and performance of the process established consarc as the leading manufacturer of esr systems worldwide. Removal of iron from commercial aluminum by electroslag. The electroslag refining process esr is a variant of the group of consumable electrode remelting processes esr, var, ebr and par for producing ingots of higher quality than that of the original material by means of controlled solidification and chemical refining. Refinement of grain size by inoculation during electroslag refining esr is known to improve the mechanical properties of 15cdv6 and modified 15cdv6 steels.
1173 1098 1418 321 703 364 209 277 180 780 567 887 1569 1217 1075 1366 1492 44 148 232 304 776 1581 1640 448 397 788 447 729 212 549 844 431 1180 138 75 1090 741 560 255 1174 1187 675 1001 849 1494