SU801962A1 - Pickup preventing coating for casting moulds and cores - Google Patents

Description

(54) ANTI-GRUNT COATING FOR CASTING AND RODS

Sulphite-alcohol brazhka6-10

WaterEverything

Chemogenic-potassium schungite powder with the content of 60-72% of natural carbon carbon has the following chemical composition, weight,%:

Naj 0.02-0.7;

Kg Oh

1.3-3.7;

SPO Oh,

0.1-1.4; MDOO, f-4.2 A (2.8-4.6;

five -

0, g4-1.5;

JjOj O.26-O, 91; 5i od the rest.

Pyrocarbon is an active non-stick material that is practically not wetted by liquid iron and has high thermochemical stability. However, at the casting temperature of the cast iron (13 O-136 O ° C), the pyrocarbon of shungite, due to its high reactivity, tends to be rapidly oxidized, which drastically reduces the effectiveness of its antiburning effect. To eliminate this phenomenon, an inhibitor is introduced into the nonstick coating, i.e. a carbon oxidation inhibitor, which uses an organic binder material — a sulfite alcohol brew. The last in the process of thermal destruction allocates significant

The amount of atomic hydrogen (more than 41%) and the minimum amount of oxygen (0.5%). The atomic hydrogen that has been introduced is adsorbed on the shungide pyrocarbon, interfering with the formation of carbon-oxygen complexes, and thus contributes to a more efficient action of shungite powder as a nonstick material. Thus, only the presence in the composition of the nonstick coating of schungite powder and the inhibitor of the oxidation reaction of sulfite – alcoholic brazci leads to the most positive results. In addition, the sulfite alcohol brew also serves as a binder material that significantly enhances the properties of the nonstick coating.

As a clay bonding coating contains bentonite.

The compositions and properties of the nonstick coating are given in table. I and 2. Table I

Shungite powder

Bentonite Sulphite-alcohol

1.5-1.8 1.7-2.01.5-1.8 1.5-1.8

0.8-1.2

0.8-1.2 0.8-1.00.8-1.0

Strength

coupling with

form

kg / cm О, gb-О, 2О ОД6-О, 2О О, 16-ОД8 0.16-ОД8

53 4

58 4

53 4

53 4

Table 2

1.6-2.0 1.0-1.2

Claims (2)

0.18-0.22 Depth approx. O, 2-O.Z ODV shape, mm 0.2-0.3 The value of the roughness of the surface of the casting, µm 14-16 The size of the burner The nonstick coating is prepared as follows. PMS and water are poured into the mixer, they are mixed for 3-5 minutes, after which bentonite and schungite powder are loaded into the mixer and the process is continued until a homogeneous mass is obtained. The paint layer applied by painting or dipping onto the surface of the mold or rod is dried at a temperature of 22 ° -27 ° C for 2 ° 60 minutes. The nonstick coating according to the invention has an increased durability of the paint layer after drying and a high thermochemical resistance, which helps to eliminate the burn and reduce the surface roughness of cast iron castings. Claims of the Invention A non-stick coating for casting molds and cores, comprising a carbon-containing refractory base, clay binder and water, characterized in that Continued table. 2 14-16t6 .2 14-16 14-17 17 0.1-0.2 Alkali strength and thermochemical resistance of the coating, as well as preventing burns on the surface of iron castings, the coating contains chemogenic-potassium schungite powder with carbon-like refractory filler containing 6 O-72% natural pyrocarbon and additionally contains a sulfite-alcohol mash in the following ratio of ingredients, wt.%: Chemogenic-potassium jute powder with a content of 6072% natural pyrocarbon 48-58 Binder clay 3-5 Sulfite-alcohol mash 6-1O Water but . The rest Sources of information taken into account during the examination 1.Catalogue NIIMASH Molding materials 1978, p. 47 2. The author's certificate of the USSR 309768, cl. In 22 SZ / OO, 1968.