The method of manufacture of baths for coating of molten zinc
The invention relates to the processing of metals, non-mechanical ways and can be used when applying the protective layer in baths for galvanizing of metal products. A method of making a bath for applying a coating of molten zinc involves creating a protective layer on the surface of the bath, in the form of a protective layer using the composition of liquid glass and graphite powder in the following ratio, wt.%: 86-82 and 14-18, respectively, and liquid glass is dissolved in hot water at 85-90oWith up to a viscosity of 30 JV, after which it add the graphite powder, the resulting mass is mixed and applied on the inner surface of the housing baths. The invention allows for the operation of the baths to reduce the consumption of zinc. table 2. The invention relates to the processing of metals, non-mechanical ways and can be used when applying the protective layer in baths for galvanizing of metal products.A known method of manufacture of baths for coating of molten zinc to the metal products, in which case the bath is made from iron in the form of sheet steel [Proskurin E. Century. and other Steel, 1987, 6, 66-69]. In another known method inside the steel fasteasy lead [USSR Author's certificate, 908934, CL 23 With 2/06, 1982].Known taken as a prototype method, in which a protective layer between the body of the bath and the metal screen comprises a mixture of (wt.) zinc oxide (2-72), boron nitride (2-70), refractory clay (5-10), bentonite clay (1-2), iron powder (4-8) and sodium silicate (10:14). [Author's certificate of the Russian Federation, 2041285, CL 23 With 2/06, 1995].The disadvantages of the method include: 1. The protective layer can only work in the presence of the screen, which requires additional costs for materials, energy and labor.2. In all known methods, the internal surface of the bath of iron, the reaction of iron with molten zinc leads to the formation of Garth zinc (zinc alloy with iron). Getting heavier than zinc, it settles on the bottom of the bath, it periodically scoop and as waste stockpiling.The objective of the proposed invention is the development of a method of manufacturing a bath for coating metal articles of molten zinc, which allows for operation of baths to reduce the consumption of zinc. This is achieved by a method in the manufacture of tubs provide a coating on the inner surface of the bath of the protective layer, contains, wt%: Sodium silicate is soluble is the reduction of consumption of zinc by reducing the interaction of molten zinc with iron, made of bath.The proposed method consists in the following: the internal surface of the bath is covered with a protective layer that is a mixture of the following components: - water glass (Na2SiO3or Na2OSiO2) powder of graphite GL-1.To obtain liquid glass solid salt Na2SiO3(Na2OSiO2) dissolved in hot (80-90oC) water with bringing viscosity of 30 CP). After this liquid glass also add a certain amount of graphite powder, the components are mixed and the resulting mixture is applied on the inner surface of the bathtub with a thickness of 2-3 mmAfter installation of the bath at the place of operation are drying the applied protective layer at a temperature of 120-140oC for 1-2 hoursFor conducting experiments produce the compositions of the protective layer are given in the table. 1.Testing of known and proposed methods performed in the production environment. Pre-made tub displacement of 4 m3sheet steel 08KP with a wall thickness of 30 mm galvanizing Process was carried out at a temperature of 47010oWith the way PR is th. Under the proposed method, the inner surface (Copyright certificate of the Russian Federation, 2041285, CL 23 With 2/06, 1995) bath covered with a protective layer, and by known methods and the method prototype inner surface was made of iron. Studies on the proposed method changed the ratio of the components of the protective layer.The test results are given in table. 2.As can be seen from the table. 2, the process according to the invention (experiment 1; 2; 3) allows comparison with the known method (6) to reduce the number of hartsink 5-6 times and to increase the amount of zinc in the primary process of galvanizing metal products.The effect is obtained due to the fact that in the proposed method uses a certain amount of strong alkali (Na2O), which interacts with the metal bath. If this quality has a negative impact when pouring the steel into the mold, covered with a protective layer containing liquid glass [Solntsev S. C., A. Tumanov So "Protective coating of metals when heated, M., engineering, 1976, s 26], in our case, the low-melting oxide Na2O interacts with the metal bath, thus providing the strong adhesion of the protective layer from the surface of the bath. When this oxide sodium also done the ü thermal conductivity properties of the protective layer and to reduce its peeling, due to the temperature difference between the metal bath and the protective layer.The revealed correlation component of the protective layer help to minimize the formation of hartsink (experiment 1, 2, 3). With increasing content of liquid glass protective layer (experiment 5) the effectiveness of the method is reduced due to the lower thermal conductivity of the protective layer and the increase due to this its exfoliation. In this case, the portion of the surface will be without the protective layer and therefore increases the interaction of the metal bath of molten zinc, resulting in an increase in the tub, hartsink compared with the proposed method. By reducing the number of liquid glass protective layer (experiment 4) deteriorates the adhesion with the metal of the bath increases uncovered surface of the bath. For this reason, increases the interaction of the metal bath of molten zinc. All this leads to increase in comparison with the proposed method the number of hartsink in the tub.The invention is implemented in production, and reduced output as a waste hartsink and due to this increased (22 tonnes) percentage of zinc used in the galvanizing process wire.
ClaimsWhen arnosti baths, characterized in that a protective layer using the composition of liquid glass and graphite powder in the following ratio, wt.%: 86-82 and 14-18, respectively, and liquid glass is dissolved in hot water at a temperature of 85-90°C. until a viscosity of 30 JV, after which it add the graphite powder, the resulting mass is mixed and applied on the inner surface of the housing baths.
FIELD: nonferrous metallurgy; fluxes and methods of the hot zinc-coating.
SUBSTANCE: the invention is pertaining to the nonferrous metallurgy, in particular to the flux and the method of deposition of the melt zinc-coatings on the metal products by dipping, in particular, to the hot zinc-coating of the steel and iron products. The flux contains from 60 up to 80 mass % of zinc chloride, from 7 up to 20 mass % of ammonium chloride, from 2 up to 20 mass % at least of one salt alkaline or earth metal, from 0,1 up to 5 mass % at least of one such compounds asNiCl2,CoCl2 andMnCl2, and from 0.1 up to 1.5 mass % at least of one of such compounds, asPbCl2,SnCl2,BiCl2 andSbCl2. The bath for the fluxing contains the mentioned above flux in the solved in water state. The method of the hot zinc-coating includes the defatting of the products, flushing, etching, flushing, the bath treatment for a fluxing, drying, the hot zinc-coating and cooling. The bath for the hot zinc-coating contains from 2 up to 56 mass % Al, from 0.005 up to 0.15 mass % Sb and-or from 0.005 up to 0.15 mass % Bi, maximum up to 0.005 mass % Pb, maximum up to 0.005 mass % Cd and maximum up to 0.002 mass % Sn, Zn - the rest. The bath for the hot zinc-coating contains up to 56 mass % Al, from 0.005 up to 0.15 mass % Sb, maximum up to 0.005 mass % Pb, maximum up to 0.005 mass % Cd and maximum up to 0.002 mass % Sn, Zn - the rest. The technical result of the invention is: production of the continuous homogeneous smooth and free from breakings coatings on the cast iron or steel products.
EFFECT: the invention ensures deposition of the continuous homogeneous smooth and free from breakings coatings on the products made out of cast iron or steel.
28 cl, 3 ex
FIELD: application of metallic coatings of zinc, aluminum and their alloys onto surface of steel strip.
SUBSTANCE: method comprises steps of preparing surface of article; applying zinc coating onto it by dipping article into bath with melt zinc; preparing mass of zinc coating by means of control system with use of gas cutters. Predetermined mass of zinc coating fed to control system is determined according to algorithm (given in the specification) in control ranges including minimum and maximum values of zinc coating mass.
EFFECT: lowered specific consumption of zinc in g/sq cm of zinc plated strip, improved efficiency of controlling process for producing predetermined mass of zinc coating at continuous hot zinc playing.
2 cl, 1 dwg, 2 ex
FIELD: metallurgy industry; methods of manufacture of the steel sheets with the two-phase structure.
SUBSTANCE: the invention is pertaining to the field of metallurgy industry, in particular, to the method of manufacture of the hot-galvanized sheets. The technical result of the invention is production of the two-phase ferrite-martensite microstructures at the ratio of the steel yielding limit at tension of no more than 0.5. The steel sheet having the two-phase microstructure is manufactured with utilization of the time/temperature cycle including the steel cementation approximately at 727-774°С and aging at 454-493°С. The steel has the following composition (in mass %): carbon - 0.02-0.20, aluminum - 0.010-0.150, titanium - maximum up to 0.01, silicon - maximum up to0.5, phosphorus - maximum up to 0.060, sulfur - maximum up to 0.030, manganese - 1.5-2.40, chromium - 0.03-1.50, molybdenum - 0.03-1.50; provided that the quantities of manganese, chromium and molybdenum have the ratio: (Mn+6Cr+10Mo) = at least 3.5 %. It is preferable, that the steel sheet is made in the form of the band treated on the production line of the continuous galvanization or the annealing and galvanization, and the product represents predominantly ferrite and martensite.
EFFECT: the invention ensures production of the two-phase ferrite-martensite microstructures of the steel sheet at the ratio of the steel yielding limit at tension of no more than zero point five.
19 cl, 6 dwg, 4 tbl, 5 ex
FIELD: nonferrous metallurgy.
SUBSTANCE: invention relates to zinc-based alloys used in various industry fields for manufacturing parts with elevated corrosion resistance requirements as well as for corrosion-resistant coatings on steel products applied by hot zinc-plating technique. Alloy of invention is composed of, wt %: aluminum 3.6-4.7, copper 0.6-1.5, magnesium 0.03-0.06, iron 0.5-1.0, lead 0.015-0.2, tin 0.01-0.1, and zinc - the balance.
EFFECT: increased corrosion resistance under salt mist conditions.
1 tbl, 5 ex
FIELD: metallurgy industry; methods of deposition of the aluminum or zinc coating on the products made out of the iron or the steel.
SUBSTANCE: the invention is pertaining to the field of metallurgy. The method of deposition of the aluminum or zinc coating on the products made out of the iron or the steel includes the preliminary preparation of the surface of the coated product, dipping of the coated product completely into the melt of the heat-transfer medium, which layer is located under the layer of the melt of the coating material, has considerably smaller thickness, curing of the coated product up to the temperature of the heat-carrier medium and the subsequent extraction of the product through the upper layer of the melt of the coating material, during which deposition of the layer of the coating is exercised. At that the preliminary preparation of the surface of the product execute by the liquid blasting using the mixture of the sharp-end split fragments of the steel or the iron shots with the dimensions lying within 0.3-1.0 mm, and the steel or the iron shots of the globular form, which size lies within 1.0-2.0 mm, at the feeding rate of the particles of 60-120 m\s. For application of the zinc coating use the flux representing the water solution, containing ZnCl2 - 400 g/liter, HCl - 10 g/liter, CuCl2 - 10 g/liter, NaCl - 50 g/liter, the surface active agent - 1 g/liter. For deposition of the aluminum coating use the alloys containing(in mass %): silicon - 3.0-7.0, manganese - 0.5-0.8, iron - up to 2.5, aluminum - the rest; manganese - 0.3-0.5, iron - up to 2.5, aluminum - the rest; zinc - 6-11, silicon - 3.0-6/0, magnesium - 0.5-1.5, tin - 0.2-0.5, titanium - 0.02-0.05, iron - up to 2.5, aluminum - the rest.
EFFECT: the invention ensures the improved quality of the aluminum or zinc coatings deposited on the products made out of the iron or steel.
13 cl, 2 ex, 1 dwg
FIELD: manufacture of steel sheets by continuous zinc-plating.
SUBSTANCE: proposed zinc-coated steel sheet has galvanic coat layer made from Zn containing aluminum at concentration of from 0.01 to 1 weight-%, the remainder being Zn and unavoidable admixtures; it contains oxide particles within 2 mcm from interface of steel sheet whose average diameter ranges from 0.001 to 1 mcm; oxides are of one type selected from Al oxide, Si oxide, Mn oxide or complex oxide containing at least two elements from Al, Si and Mn. Heating temperature at re-crystallization annealing stage in reduction furnace ranges from 650°C to 900°C; steel sheet is passed through atmosphere where ratio of partial pressure of water steam PH2O and partial pressure of hydrogen PH2 satisfies the following inequality: forming the oxide in area reaching the depth of 2 mcm from surface of steel sheet; then, sheet is subjected to zinc-plating.
EFFECT: enhanced strength and deformability; possesses good ability for adhesion with galvanic layer; avoidance of defects in galvanic coat.
4 cl, 1 dwg, 3 tbl