SU619544A1 - Borating composition - Google Patents

Description

(54) FORMULATION FORMULATION

This invention relates to chemical heat treatment and may be priyunena as a saturating medium for duff-bored steel products.

A known composition for boronization, containing boron carbide, oxides of iron, silicon, boron, powdered aluminium and sodium fluoride at a ratio of wt%:

Carbide boron 50-60

Iron Oxide5-15

Silicon oxide 5-10

Boron oxide 5-15

Aluminum5-10

Sodium fluoride 5-7

As a binder for this composition, hydrolyzed ethyl sulphate 11 is used; However, the content of chemically pure iron oxide, as well as silicon oxide and powdered aluminum in this composition not only increases the cost of coating, increases the complexity of preparation and impairs its processability, but also leads to a decrease in the speed of formation of borisp to the layers.

Also known is a composition for boronation, taken as a prototype, containing components, wt%:

Boron carbide58.0-64.0

Bura10,0-13,0

Ammonium Chloride0 -1.5

Sodium Chloride1,1-1,5

Iron Powder Else 12}

This composition allows to carry out boronation in an oxidizing environment without protective equipment. The disadvantage of this composition is the insufficient rate of formation of boride layers. The bottom of the products of steel 45 and 40 after heating at 950 ° C for 6 hours, the depth of the layer is 0.14-0.16 mm. In addition, when using this composition as a wash, the presence of borax and sodium chloride gives it increased fluidity, thereby limiting the scope of its technological application due to its possible draining.

The use of ammonium chloride as an activator is also undesirable, since during heating an intensive decomposition of this additive occurs with the formation of a large amount of gaseous products. This often leads to a violation of the continuity of coating and increasing its tendency to local burnout. Lastly, the stability of the boronization process in the plaster is reduced to an extremely strong degree. The aim of the invention is to increase the saturation rate. The goal is achieved by the proposed composition for boronation, which contains boron and boron boron as the boron-containing substance, iron oxide as iron powder, and boron fluoride as an activator, in the following ratio of components, wt.%: Boron carbide45-60 Boron anhydride2-10 sodium fluoride5-10 iron oxide25-40 Hydrolyzed ethyl acetate is used as a binder for the coating. Example. Dafusioshue boring of steel forging die was brought

45

40

The components for the preparation of the coating were used in the form of technical boron carbide GOST 3647-71 and 5744-74, iron oxide — waste from forge-thermal production, boron anhydride grade 4 GOST 10068-62, sodium fluoride of the GOST 4463-66 brand.

The thickness of the borne steel layer 45 at 900 ° C for 4 hours is 0.189 mm, which indicates that the saturating

0.177

0.153

0.142 0.236 0.177 0.212 0.201 0.236

ability of the proposed structure in comparison with the prototype.

Claims (2)

Invention Formula The composition of boronization containing boron-containing substance, iron powder - and activator, is different; in order to increase the rate of saturation, it contains as a boron-containing substance; VA boron carbide and boric anhydride, iron oxide as iron powder, and sodium fluoride as an activator. 4HSNMFTSR dimensions of 470 x 130 x 150 mm. The coating was prepared by mixing poro-abs-like components (fraction size, mm) with hydrolyzed ethyl silicate. A coating of 3-4 mm thick was applied on a stamp engraving with a shot of an ishatzle. After drying for 10–20 min at room temperature in air, the stamp was placed in an electric furnace C-60 heated to 900 ° C. Further processing was carried out according to the technology of heat treatment adopted for this steel grade: heating to a temperature of 900 ° C, holding at 900 ° C for 1 h, heating to a quenching temperature of 970 ± 10 ° C, holding at a hardening temperature for 2 h, hardening in oil, tempering at 620 ° C for 3 h. When hardening in a masp, the coating lost integrity and was separated from the surface of the equilibrium. After quenching, the shredding remains were removed from the surface with a metal brush. The results of diffusion hardening of die steels 5ХНМ, 40ХСМФ and 4ХСНМЦР are presented in the table. 619544 e in the following ratio of components. wt.%: Boron carbide 45-60 Boric anhydride 2–10 1 o1жsty sodium 5–10 Iron oxide 25–40 Q Sources of information received during examination: 1. USSR author's certificate No. 2338268, / 22.02, C 23 C 9 / 02. 1976. 2. Authors certificate of USSR N524858, C 23 C, 9/04, 1976.