SU973665A1 - Pulverulent composition for complex treatment of products of aluminium alloys - Google Patents

Description

(54) POWDER COMPOSITION FOR COMPLEX TREATMENT OF ALUMINUM ALLOY PRODUCTS

The invention relates to metallurgy, in particular to the chemical heat treatment of aluminum and its alloy in powder media, and can be used to improve the performance characteristics of products made from aluminum and its alloys used in the instrument-making, aircraft and engineering industries. The known composition of the powder saturating medium based on chromium and titanium used for the chemical-thermal treatment of steel products. However, as a result of the processing of aluminum alloys in known compositions, diffusion layers cannot be obtained on them. The closest to the invention in technical essence and the achieved effect is the composition 2 for chromatising the products from aluminum alloys, containing, in May.%: Aluminum oxide 10-20 Chromium oxide 8p6-10.6 Titanium dioxide 8.6-10.6 Aluminum 27.8 -29.8 Zinc31-38 Ammonium Chloride 0.5-1.5 Fluorspar 0.5-1.5 However, as a result of treatment at 5000 s for 4 hours of alloy D16, a diffusion zinc-chromo titanium layer with a thickness of 180 µm forms on it. When working parts made of aluminum alloys under the conditions of exposure to corrosive media while simultaneously wearing them, such a thickness of the layer is not sufficient. The aim of the invention is to increase the thickness of the diffusion layer. This goal is achieved by the fact that a eutectic mixture of borax (Na,) and potassium fluorideboard (KBF) is additionally introduced into the powder mixture containing alumina, chromium oxide, titanium dioxide, aluminum, ammonium chloride, zinc in the following ratio of ingredients, wt. : Aluminum oxide 10-20 Oxide of chromium8,6-10,6 Titanium dioxide 8.6-10.6 Aluminum27.8-29.8 Zinc31-33 Ammonium chloride 0.5-1.5 Eutectic mixture of borax and fluorine borate 0.5 -1.5

Zinc-chromotitanation in the proposed powder medium is carried out in containers with fusible closures at 500 ° C for 4 hours. At the same time, a differential alloy is formed on the D16 alloy.

10% AE.iOj + 27.8% .AC + 10.6% CrO + 10.6% TiCL4-38% Zn +

fi, 5%, 5 sard

Proposed

15% Ae2Oj + 28.8% AB4-9.6% SG2Oz + 9.6% T10, g, + 36% Zn + +0.5, 5% eutectic ()

20% Ae205 + 29.8% AB + 8.6% Ci; p3 + 8.6% TiOo + 31% Zn + + 1% NH4C “+ 1% Eutectic (. + KBF)

Claims (1)

10% Ae2 | Oz + 27.8% Ae + l6.6% C1; pz + 10.6% TiO2 + 38% Zn + +1.5 NH4Ce + l, 5% eutectic () From the data presented, it follows. what. the use of the proposed composition allows to obtain a diffusion layer 1.4-1.5 times larger than when using a known composition, which allows to significantly expand the areas of practical use of diffusion-hardened aluminum alloys, the invention Formulation powder for complex processing of products from aluminum alloys, containing alumina, chromium oxide, titanium dioxide, aluminum, ammonium chloride, zinc, are different from the fact that, in order to increase the thickness of the diffusion layer, it is additionally sof Zeon layer thickness of 260 280 microns. Comparative data on the processing of the alloy D16 from the well-known and proposed compositions are given in the table, 5J30 180 500 260 500 4 270 500 280 holds a eutectic mixture of borax and potassium fluoroborate in the following ratio of components, wt.%: Aluminum oxide 10-20 Chromium oxide 8.6-10.6 Titanium dioxide 8.6-10.6 Aluminum. -.27.8-29.8 Zinc 31-38 Ammonium Chloride 0.5-1.5 Eutectic mixture of borax and potassium fluoroborate 0.5-1.5 Sources of information, taken into account during the examination, Zemskov G, in ., Kogan. G.L., Multicomponent diffusion saturation of metals and alloys, M., Metallurgi, 1978, p. ,,12. 2, USSR Author's Certificate in Application 2995638 / 22-02, cl. C 23 C 9/02, 1980.