SU1127724A1 - Separating coating - Google Patents

Abstract

Separation, mainly for the manufacture of multilayer packs of hard-to-deform steels, containing magnesite powder, binder and water, characterized in that, in order to improve the quality of products, ferrous sulphate is used at the following ratio, wt.% : Magnesite powder 48.0-36.0 Ferrous sulfate 12.6-28.0 Water39.4-36.0.

Description

1C | Yu

Nj

The invention relates to ferrous metallurgy, in particular to the production of bimetallic sheets in a batch process and the production of hard steels and alloys in the shell.

Known separation coating containing vol.%: Magnesite 78.0-87.5, magnesium sulphate 12.5-25.0 1,

 The disadvantages of the known separation coating are that the mixture retains the creamy state for 10-12 minutes after preparation, which is less than the time required for applying to the surfaces to be divided; applied with an uneven layer, which leads to uneven heating of the packages along the section and unevenness of the sheets in thickness; promotes the formation of non-welded areas (bundles) in double-layer sheets; maintains a solid state during deformation, takes the necessary ductility at a temperature of 300-450 ° C above the temperature at which the packs begin to deform; lags the metal of the cladding layer or billets of hard steels and alloys, which are separated from the metal, and prevents the movement of metal volumes, which contributes to the destruction of billets during rolling; during deformation, solid particles penetrate the metal surface and are removed only by etching.

These phenomena have a negative effect on the quality of double-layer sheets, the consumption of metal for the manufacture of products increases due to additional waste associated with the destruction of packages and the removal of non-weldable areas (bundles) of double-layer sheets.

The aim of the invention is to improve the quality of products.

The goal is achieved by the fact that in the separation coating, mainly for the manufacture of multilayer packs of hard steel, containing magnesite powder, binder and water, iron sulfate is used as a binder, in the following ratio of components, wt./o.

Magnesite powder 48.0-36.0

Ferrous sulphate12,6-28,0

Water 39.4-36.0.

For the manufacture of the coating of the proposed composition of powdered materials (wt.%) Magnesite (48.0-36.0 wt. ° / o) and iron sulfate (12.6-28.0 wt.), Having the following technical characteristics (TU-14 -200-263-77): passage through the mesh No. 008 at least 90 vol.%, Stirred, after which water 39.4-36.0 is added and the movement continues manually or with the help of a mixer (such as a concrete mixer) to the estimated form neither The resulting mixture is applied with a brush or gun-sprayed with a layer of 0.2-0.5 mm thick on separable degreased surfaces of plates or blanks from carbon, alloyed, stainless steels, as well as nickel-chromium-based alloys, then the plates or blanks are in air. at 10-30 ° C for 2-3 hours or in a heating furnace at 50-80 ° C for 30-60 minutes.

Next, a four-layer pax is assembled (to produce two-layer sheets) from two slabs of carbon or low-alloyed steel, two stainless steel or alloy steel plates are laid between the slabs, one of which has a separating coating along the plane of contact with the other plate. Assembled package with a connecting strap sealed by welding around the perimeter.

A three-layer package (rolled in a shell) consisting of two layers of carbon steel or low-alloy steel shells is assembled; a blank of hard-to-deform steel is laid between the shell shells and a separation coating is applied along the plane of contact with the shell metals. Assembled package with a connecting strap sealed by welding around the perimeter.

Depending on the chemical composition of steels and alloys up to 1190-1350 ° C at a speed of 5-6 degrees / min, the rolling packs are heated, maintained at this temperature 1.0-1.5 h, the total reduction is from 80 to 94 / o, rolling finish at 1150-900 ° C.

Example 1. At the maximum ratio of components, a separate coating comprising in wt.%:

Magnesite48,0

Ferrous sulphate12,6

Water39,4

by this method saves it. creamy state for 30-35 minutes; applied in an even continuous layer with a thickness of 0.2-0.3 mm; at package heating temperatures (1190-1350 ° C), does not decompose, does not melt, and does not flow to the contact surfaces of the components of the package; at temperatures of hot deformation (1300900 ° C), it retains plasticity and does not penetrate into the surface of the separable plates of the cladding layer or blanks of hard-to-deform steels and alloys.

With an increase in the content of magnesite coating more than 48.0% by weight, iron sulfate less than 12.6% by weight, water more than 39.4% by weight, no creamy mass is formed that is suitable for uniform coating of the surfaces to be divided, the components of the coating are not glued between by myself. Such coating

falls off from the surface of the plates of the cladding layer or blanks of hard-to-become steels and alloys during their transportation.

Example 2. At nominal ratios of the components, a separation coating comprising

Magnesite41.0

Iron sulfate21.0

Water38,0

according to the described method, maintains a creamy state for 30-35 minutes; applied evenly in a thickness of 0.3-0.4 mm; at the heating temperatures of the package 1190-1350 ° C, it does not decompose, does not melt and does not flow onto the contact surfaces of the components of the package, which eliminates the formation of discontinuities (delaminations) in the two-layer sheets; provides for rolling to obtain high adhesion strength of layers of two-layer sheets (CP 30-40 kgf / mm, according to GOST 10885-75 Ser 15 kgf / mm where Ter is the value of shear resistance, which characterizes the strength of adhesion of layers in double-layer sheets); at temperatures of hot deformation (1300-900 ° C) does not penetrate into the metal surface; it is easily deformed with the same stretching as the metal components, without destroying the packages.

Example 3. At minimum ratios of the components, a separation coating comprising in wt.%.

Magnesite36,0

Iron sulfate28.0

Water36.0

according to the described method, maintains a creamy state for 30 minutes; applied evenly with a thickness of 0.4-0.5 mm; at the package heating temperatures (1190-1350 ° C) it does not decompose, does not melt and does not flow onto the contact surfaces of the package components, which eliminates the formation of discontinuities (delaminations) in two-layer sheets; provides for rolling the production of double-layer sheets with high bond strength of the layers.

When the content in the coating in wt.% Magnesite less than 36.0 wt. ° / o, sulphate of iron more than 28.0 wt.%, Water less than 36.0 may / o mixture hardens after 5-8 minutes and becomes unsuitable for application on dividing surfaces.

The present invention in comparison with the known has the following technical advantages.

The separation coating of the proposed composition retains the creamy state during the time it is applied to the separation surfaces (30-35 minutes) -. It is an even layer with a thickness of 0.2–0.5 mm, which contributes to a uniform heating of the bags over the section before rolling and

obtaining equally thick two-layer sheets. The thickness variation of the double-layer sheets along the perimeter is O, -0.3 mm. The known separation coating on the 5 basis of magnesite and magnesium sulphate retains a creamy state for 10-12 minutes, then thickens and is applied unevenly on the surfaces to be divided, the thickness of the separation coating layer being 0.5-1.0 mm, which leads to uneven heating the package across the section before rolling and obtaining non-equi-thick two-layer sheets: the thickness difference around the perimeter of two-layer sheets is 0.5-1.0 mm, which displays individual sheets

5 out of tolerance according to GOST 10885-75. The proposed separation coating at heating temperatures (1190-1350 ° C) does not decompose, does not form gaseous substances that oxidize the contact surfaces of the components of the package, which eliminates the formation of discontinuities (delaminations) in two-layer sheets, provides for rolling to obtain high adhesion strength of the component sheets two-layer. (Ter 30-40kgs / mm2, (according to GOST 10885-75)

5 fcp 15 kgf / mm2, where Ser. is the amount of resistance to shear, which characterizes the adhesion strength of the layers of two-layer sheets).

Known separation coating contributes to the formation of non-welded areas (bundles) along the plane of two layer sheets. The strength of adhesion is uneven along the plane of two-layer sheets (cf. 0-25 kgf / mm).

The separation coating of the proposed composition at the temperature of package deformation (1300-900 ° C) does not penetrate into the surface of the plates and blanks, has the same stretch with the metal, promotes sliding of metal volumes without destroying the packages.

The known separation coating based on magnesite and magnesium sulphate takes the necessary ductility at a temperature of 300 to 450 ° C above the deformation temperature of the bags, lags behind the metal of the separable plates,

5 prevents the bags from moving during rolling.

The use of separation coating containing in w / o Magnesite48, 0-36.0

Ferrous sulphate12,6-28,0

0 Water39.4-36.0

contributes to the production of double-layer sheets with a minimum thickness variation, high adhesion strength of the main and cladding layers, eliminates the destruction of the packages during rolling. In this case, the separation coating is easily removed from the surface of the sheets (showered) when they are finished. The consumption of metal for the production of 1 ton of products in comparison with the known decreases by 80-100 kg. The estimated economic effect of more than 200 thousand rubles. Industrial tests have been carried out in which all qualities of the separating wash are confirmed. The separation coating of the proposed composition prepared according to the described method retains a creamy state for 30-35 minutes; applied in an even continuous layer with a thickness of 0.2-0.5 at the heating temperatures of the packages (1190-1350 ° C) does not decompose, does not melt, and does not leak onto the contact surfaces of the components of the package; at temperatures of hot deformation (1300-900 ° C), it retains plasticity and does not penetrate into the surface of separable plates and blanks; provides, during rolling, high adhesion strength of layers of two-layer sheets Cicp (30-40 kgf / mm according to GOST 10885-75 fcp (15 kgf / mm); easily deformed with the same suction as the metal without destroying the pouches; when finishing two-layer sheets, the separation coating is easily removed (showered) from the surface. Industrial tests are carried out on 10,000 bags. The reduction in metal consumption for the production of 1 ton of product is 80-100 kg as compared with the known invention.

Claims (1)

DIVIDING COATING, mainly for the manufacture of multilayer bags of hardly deformed steels, containing magnesite powder, a binder and water, characterized in that, in order to improve the quality of products, as a binder change sulphate of iron at the next ratio, wt. ° / ₀ : Magnesite powder 48.0–36.0 Iron sulfate 12.6–28.0 Water 39.4-36.0.