SU861381A1 - Composition for hot treatment of metals - Google Patents

Description

(54) COMPOSITION FOR HOT TREATMENT OF METALS

one

The invention relates to phosphate compositions used in the form of a dry powder, an aqueous solution or technological lubricant in the thermochemical processing of metals and alloys, in particular copper alloys.

Known compositions based on potassium phosphate, containing additional borates p.

The disadvantage of this composition is a low melting point.

Closest to the invention of the technical essence and the achieved result is a composition for the treatment of metals based on potassium metaphosphate, which additionally contains oxides of potassium, iron or aluminum z.

During hot processing of alloyed steels and other alloys, potassium phosphates melt and react with the oxidized surface of the product. During the reaction period, a stable film is formed which adheres well to the metal surface and prevents it from sintering with the working surface of the equipment. However, with positive qualities, the composition has disadvantages and limitations in application. Thus, the oxides of iron and aluminum reduce the solubility of the composition in water, increasing -. The softening and melting temperature of the composition is reduced, and the quality of surface treatment deteriorates.

10 products made of copper alloys due to corrosion and deposition of phosphates on the surface, as a result of which the metal surface remains turbid.

The aim of the invention is to increase the purity and brilliance of machined copper alloy products.

This goal is achieved by the fact that the known composition for the hot processing of metals based on metaphosphate and potassium additionally contains acidic sodium and manganese phosphates, sodium tetraborate and silica with the following

... the ratio of components, weight. %: Sour monosubstituted sodium phosphates 2-40 Sour disubstituted sodium phosphates 10-54 Sour monosubstituted manganese phosphates 1-5 Sodium tetraborate 2-5 Silica 0.1-0.5 Potassium metaphosphate Else Introduction to sodium and potassium phosphates leads to the reaction proceeds only with the oxide layer without affecting the metal, the phosphate-forming lubricant formed is elastic, adheres well to the copper otOTOBKH surface, and when cooled easily climbs with it, in addition, the melting point of the composition decreases. The chemistry of the phosphate composition is as follows. The phosphate composition deposited on the hot metal forms a melt of uniform thickness. In addition, as a result of a chemical reaction, the scale layer passes into copper phosphate, which in turn acts as a lubricant. This stable good adhesion to the surface with a lubricating film prevents contact with air, eliminating the least oxidation, as well as contact with the processing tool, eliminating the possibility of sintering metals and reducing tool wear. Heat treatment of metals with phosphate compositions is carried out as follows. For the tests, plates (20x30x3 mm) or discs (diameter 30 mm) are taken, the surface of which is treated according to the 8-9 purity class. The metal samples are immersed in a melt of a phosphate composition having a temperature. 600-700s, for example for 2 minutes. The image is removed from the melt. Cool in air. In this case, most of the phosphate composition from the surface of the sample is spontaneously removed due to the difference in the coefficients of linear expansion of the metal and the phosphate composition. The residual phosphate composition from the surface of the metal is removed by dissolving in water. The purity class and degree of surface gloss of the metal treated with the 8 8 IT method are determined by comparison with the voucher samples. Recipe phosatnyh compositions are given in table. I. The surface remaining of the copper alloys after treatment with phosphate compounds is listed in Table. 2. From a comparison of the data table. Figures 1 and 2 show that the composition achieves the goal at the indicated ratios of the components. The compositions are readily soluble in water, the softening temperature is lower. The melts of phosphate compositions 1, 2 and 3 wet the metal surface well, the oxide film quickly dissolves, and the surface becomes shiny. To assess the possibility of using phosphate compounds as an antifriction lubricant, a cooling lubricant (coolant) is prepared: phosphatol of the following composition,%: Phosphate composition (Table 1) 25 Polyacrylamide 3 Stearox-6 ethylene) 0.05 Proxanol-224 (block copolymer of ethylene oxides and propylene) 0, Water 71.8 The number of phosphate is determined by the number of the composition (Table 1). Then the friction coefficient is measured according to the known method of compression of rings made of metal to be treated,a stamping press at temp round hot stamping. The coolant is then applied to the surface of the die or to a cold workpiece, which is then heated. The coefficient of friction, thus defined, for phosphatol No. 1 and 3 is 0.12 and 0.10. The rather low coefficient of friction indicates the possibility of using the developed compositions not only for the heat treatment of copper alloys, but also as coolant and lubricants for hot metal forming (stamping, pressing).

34.0 42.0

, Croze

Na 0 4.0

58.0 36.0

NaH2, POij2.0: 115.0

Ml (H, P04) 2 2.8

HBO.

KF-HF

t)

7, 8 - the standard.

Table 1

57.0 58.0 89 88

75 30.0 30.0 1 I 0, 8 O, -6

Table 2

Claims (2)

Claim Composition for hot processing of metals based on potassium metaphosphate, characterized in that, in order to increase the purity and gloss of the processed products from copper alloys, it additionally contains acid phosphates of sodium and manganese, sodium tetraborate and silicon oxide in the following ratio, wt.%: Acidic Monosubstituted Sodium Phosphates 2-40 Acidic Disubstituted Sodium Phosphates 10-54 55 Acid monosubstituted manganese phosphates Sodium tetraborate Silicon oxide Potassium metaphosphate fifteen 2-5 0.1-0.5 Else