LV14504B - The mass of glass-crystalline enamel type coating on the steel. - Google Patents

Abstract

There is invented composition of glass-crystalline enamel type coating on the steel alloy, which provides reducing required amount of pigment. At the same time is provided reducing crystallization time of enamel surfacing due to formation of crystalline phases of crystobalite and tridimite therein. For their part that provides the necessary thermal expansion of enamel coating. As an accelerator for crystallization of enamel (crystallizer) is added mixture of ground sand (1 part by weight) and soda (3 parts by weight) which is thermally treated within 1-2 hours at a temperature of 1000 to 1200 centigrade and after that is additionally ground. The mentioned crystallizer is added in amount of 30 to 70 parts by weight per 100 parts by weight of enamel frit.

Description

Description of the Invention

The present invention relates to a bulk composition for a vitreous crystalline enamel coating on an alloyed chromium nickel steel characterized by increased thermal expansion.

In this case, the components necessary for the setting and stabilization of the enamel slipper (clay, bentonite, sodium nitrite, borax) are not included in the composition, but special additives (various refractory oxides, chamotte, phosphates, pigments, etc.) including the enamel frit.

There is a known mass of vitreous-crystalline enamel coating, which provides the necessary thermal expansion of the enamel layer due to the crystalline phases crystalline and tridymite being released during the heat treatment. But the release of these crystalline phases is achieved by a special heat treatment: curing at 900 ° C for 2 hours. [1],

An enamel mass composition with reduced crystallization time has been developed, which results in crystallization of cristobalite and tridymite in the coating during melting, thus providing the necessary thermal expansion of the enamel coating. But to achieve these goals, a large amount of 40 to 100 parts by weight of pigment (K 6038 - chromium-iron oxide mixture) [2] (prototype) must be added.

Designation of pigment K 6038: Cr-Fe tiefshwarz (deep black) Reimbold-strick (CHEMISCH-KERAMISCHE WERKE).

The object of the present invention is to provide an enamel mass composition with reduced amount of pigment required while maintaining a short crystallization time. The objective is achieved by using a high S1O2-containing enamel frit and adding 30 to 70 parts by weight per 100 parts by weight of the crystallizer (crystallization enhancer) in addition to the pigment. The crystallizer is a mixture of 100 parts by weight of ground sand and 3 parts by weight of soda (anhydrous), heated for 1-2 hours. 1000-1200 ° C and additionally crushed.

The applied mass composition provides accelerated crystallization of the enamel coating and the release of cristobalite and tridymite (see Table 1). For comparison, the basis (prototype) is the mass composition with 40-100 parts by weight of pigment additive [2].

Table 1

Composition of enamel coating, parts by weight Conditions for crystallization Crystalline phase in the coating Frite -100 Pigment - 40-100 Melting last 20 minutes, Christobalite Tridymitis

(prototype) cooling with oven Frite -100 Pigments-5 Crystallizer - 70 Thawing last 20 minutes, cooling with oven Christobalite Tridymitis Frite - 100 Pigment - 20th Crystallizer - 30 Thawing last 20 minutes, cooling with oven Christobalite Tridymitis

As can be seen from Table 1, the proposed mass composition with the reduced amount of pigment required provides analogy with the prototype, crystallization rules and crystalline phase separation in the enamel coating.

References:

1. USSR aut.pl.No. 391082, MKL CO3C 7/04, 1973. Enamel for steel (authors: L.Bidmanis, J.Eiduks, P.Pauks).

2. LR Patents LV14401 B.Jnt.Cl.C03C 8/00, C23D 5/00. Mass for enamel type coating on steel (authors: L.Bidmanis. J.Liepiņš, G.Mezinskis, A.Cimmers, LPavIovska, 17.06.2011) (prototype).

Claims (2)

Claims 1. A glass-crystalline enamel mass for steel coating comprises an enamel frit and a pigment, characterized in that, in order to reduce the amount of pigment needed, while maintaining the shortened crystallization time and the release of cristobalite and tridymite, the mass additionally comprises parts by weight per 100 parts by weight frites. 2. The weight of the glass-crystalline enamel coating on the steel according to claim 1, characterized in that the crystallizer is made from a mixture of 100 parts by weight of ground sand and 3 parts by weight of soda (anhydrous).