RU2510684C1 - Method for obtaining briquette to obtain titanium- and zirconium-containing cast iron - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgical, casting production, and namely to production of cast irons operating under abrasive wear conditions. The method involves preparation of a mixture of initial material with further moulding. As initial material, crushed metal chips and metal scrap in the form of scale and scrap of ferrous metals, which are mixed with cryolite, and zircon and ilmenite concentrate, are used. Water solution (40%) of glyoxal is used as the binding agent. Components of the briquette are contained in the following ratio, wt %: metal chips and metal scraps in the form of scale and scrap of ferrous metals - 60, cryolite - 20, zircon concentrate - 7.5, ilmenite concentrate - 7.5, water solution (40%) of glyoxal - 5. The obtained mixture is homogenised by mixing, formed into a briquette by pressing and dried during 3 hours at 80°C.

EFFECT: according to the invention, use of briquettes will allow increasing wear resistance of the obtained cast iron.

2 cl, 2 dwg, 2 ex

Description

The invention relates to metallurgical, foundry, in particular to the manufacture of cast irons operating in conditions of abrasive wear.

A known method of briquetting metal chips (RF patent No. 2251580, C22B 1/248, C22B 1/243, 05/10/2005). The invention relates to metallurgy and can be used in the processing of metal chips and sludge metalworking waste. The method of briquetting metal chips, including its crushing, cleaning, heating, adding sludge, binder material, mixing and compaction in the mold. As a binder material use a water-cement paste of 30-40% concentration in an amount of 4-7% by weight of the briquette. The invention will allow to extrude low-plastic hardly deformable chips and increase the strength of briquettes. The main disadvantages:

1) The method does not provide for the introduction of alloying and / or modifying additives into the briquette.

2) Used as a binder cement will adversely affect the quality of the smelted metal.

A known method of producing briquettes from dispersed materials (RF Patent No. 2274666, C22B 1/243, publ. 04/20/2006). The invention relates to the field of metallurgy, mainly the production of briquettes from dispersed materials formed during the crushing of ferrosilicon and its fractionation. The components of the mixture, consisting mainly of dispersed silicon-containing filler - the main part of the mixture, as well as the powder component of the binder and an aqueous 10-30% solution of caustic soda, are dosed, they are mixed, pressed and hardened. As a powdery component of the binder, self-scattering slag of ferrochrome production is used in an amount of 3-25%. The caustic soda solution is heated to a temperature of 30-100 ° C before dosing. The invention will increase the strength of briquettes, reduce the time of their hardening, reduce the loss of active silicon in briquettes, increase their solubility in molten metals and alloys. A disadvantage of the known invention is the use of caustic soda as a binder, which requires special conditions for the production of briquettes and their storage.

A known method of manufacturing briquettes from waste ferroalloys (RF Patent No. 2272082, C22B 1/243, publ. 20.03.2006), selected as a prototype. The manufacture of briquettes from ferroalloy waste includes the preparation of a mixture of the starting material with an aqueous solution of liquid glass, processing the mixture with a water repellent in preparation for briquetting, and pressing the material into briquettes. As a water repellent agent, solid carbon dioxide is introduced into the mixture upon exit of the mixture from the mixer and before loading into the forming tooling. EFFECT: invention enables to ensure a high compaction rate, reduce the adherence of the mixture to the forming tooling, and increase the density and strength of briquettes. The disadvantages of the known invention is that it allows you to process only waste production of ferroalloys. For its manufacture, solid carbon dioxide is used, which during the smelting process using the obtained briquette can lead to the formation of non-metallic inclusions and gas shells.

The objective of the present invention is to develop a method for producing a briquette for producing titanium and zirconium-containing cast iron in order to increase the corrosion resistance and operational characteristics of metals and alloys through the use of cheap materials.

The problem is solved in that the method for producing a briquette for producing titanium and zirconium-containing cast iron involves preparing a mixture of the starting material with subsequent molding, but unlike the prototype, ground metal chips and other metal waste (scale, scrap of ferrous metals) are used as the starting material, mixed with cryolite, zircon and ilmenite concentrate, and glyoxal 40% is introduced as a binder, in the following ratio of components, wt.%

Metal chip and metal waste (scale, ferrous metal scrap) - 60%

Cryolite - 20%

Zircon concentrate - 7.5%

Ilmenite concentrate - 7.5%

Glyoxalum (solution 40%) - 5%.

The resulting mixture is homogenized by stirring, compacted into briquettes by compression, which are then dried for 3 hours at 80 ° C.

Briquette preparation for obtaining titanium and zirconium-containing cast iron is carried out in 3 stages. Metal shavings, scale, scrap of ferrous metals are crushed to a fraction of 2-3 cm and mixed for 5 minutes in batch mixers. Then, zircon, ilmenite concentrate and cryolite are fed into the mixer. The mixture is stirred for 10 minutes and then a 40% glyoxal solution is added. Further mixing is carried out for 5 minutes, after which the mixture is unloaded into molds and molded under light loads. The resulting briquettes are dried for 3 hours at a temperature of 80 ° C.

An example of a specific embodiment of the invention is given below.

Example 1

A mixture of metal chips and scale (2-3 mm fraction) in an amount of 60 wt.% Was pre-mixed in a batch mixer with zircon, ilmenite concentrate and cryolite for 15 minutes. A crosslinking agent — a 40% glyoxal solution — was supplied in an amount of 5%. The mixture was distributed into 15 × 30 cm molds and pressed under a pressure of 0.3 MPa. Pressed briquettes entered the drying oven and kept at a temperature of 80 ° C for 3 hours.

Example 2

A mixture of ground scrap of ferrous metals, zircon, ilmenite concentrate, cryolite and 40% glyoxal solution was initially loaded on the same equipment. The mixture was stirred for 30 minutes, drying is carried out, as in example 1.

The advantages of the present invention are:

1) The use of ore concentrates as titanium and zirconium-containing additives, which helps to reduce the cost.

2) Use as a crosslinking agent of an aqueous solution of glyoxal, which decomposes into gaseous products.

3) No need to use high pressures when receiving briquettes.

Figure 1 presents the results of studies of the loss of mass of samples under conditions of abrasive wear, which confirms the increase in wear resistance of cast iron when using the present invention.

Figure 2 presents the results of a study of the weight loss of cast iron samples when exposed to hydrochloric acid. The data presented show that when the content of briquettes in the mixture is 30%, the maximum effect of increasing corrosion resistance is achieved.

Claims (2)

1. A method of obtaining a briquette for producing titanium and zirconium-containing cast iron, comprising preparing a mixture of the starting material with subsequent molding, characterized in that the starting material is crushed metal shavings and metal waste in the form of scale and scrap of ferrous metals mixed with cryolite, zircon and ilmenite concentrate, and as a binder, a 40% aqueous solution of glyoxal is introduced, in the following ratio of components, wt.%:
metal shavings and metal waste in the form of scale and scrap of ferrous metals 60 cryolite twenty zircon concentrate 7.5 ilmenite concentrate 7.5 40% aqueous glyoxal solution 5 2. The method according to claim 1, characterized in that the resulting mixture is homogenized by stirring, formed into a briquette by pressing, which is then dried for 3 hours at 80 ° C.

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