SU1704900A1 - Suspension for investment casting molds and method of its treatment - Google Patents

Abstract

The invention relates to mold materials obtained from melted models and methods for processing these molds. The purpose of the invention is to improve the quality of the surface of the molds. They are made from a slurry that contains (in May.%) Liquid glass 13.7-21.9; lactic acid 0.87-1) 3; an aqueous solution of sodium tripolyphosphate 20-28.3; surfactant 0.1-0.3; antifoam 0.2-0; refractory filler rest. Each layer of the specified suspension applied to flea models is treated in an acidic solution of composition, May. %; boric acid 2-4; calcium chloride 10-30; water the rest. The treatment of the shell with a hardening solution is carried out by lowering the block into this solution for 10-15 minutes. The strength of the shell forms is, MPa: in the wet state, 12-16.8; after calcining 12.8-19.1. There are no cracks in the mold, and the specific area of the ruptured surface of the mold amounts to 0.11 cm2 / cm2. 2 sec. f-ly, 4 tab. Yo

Description

The invention relates to foundry, in particular, to the manufacture of foundry shell molds for produced models, and can be used in the manufacture of precision castings.

The purpose of the invention is to improve the quality of the surface of the mold shell.

The essence of the technical solutions (the composition of the slurry and the method of processing the mold membranes) are as follows.

Shell casings are produced by melted models (according to the generally accepted technology of this method) from a slurry composition on a liquid glass binder, which contains, in May. %:

Liquid glass13.7-21,9

Lactic acid 0.87-1.3

An aqueous solution of sodium trisodium phosphate. 20.0-28.3 Surfactant 0.1-0.3 Antifoam 0.2-0.6 Refractory Refine Remaining The first layer of the shell is treated by immersing the model block in an acidic aqueous solution of the composition, May. %: Boron acid 2-4 Calcium chloride 10-30 Water Else In this solution, the first layer is aged for 10-15 minutes.

Lactic acid is added to the suspension, which is used to form the sheaths, to reduce

I

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each of the subsequent ones facilitates the drilling of a mold forbidding under the same conditions for 60 sheets during treatment with a solution of min. Melting model composition of the wire with acidic properties. Boric acid is a viscous product of 5 acid at a temperature of 98 ° C for 15 with adhesive properties. The presence of these min. The calcining was carried out in the shaft furnace of the properties of the United States 10.10 10/10 form of hares forming at 780 ° С for 1.5 days and cross-braised t4. „- - ears. which is without reference filler. The filling of the alloy was obtained by obtaining high-quality wt St45 produced in the formative shell, the surface of the formforo5ol1) ca 10 heated to 360 ° C in the supporting filler.

Tripolyphosphine sodium eliminates the tic-Criterion of the quality of the surface of the pharyngeal structures of structures or suspended shell is the specific area of winters, which ensures the achievement of the eroded surface and the specific length of the target from the retention. on cracks. To determine the specific surface of the physicochemical essence of the method 15 of the scoured surface of the molds on the basis of tin-shaped shells, it was printed on a penny from a liquid glass, acid, phosphometallic paper, using an alkali metal copying salt. In order to determine the specific length of the TSP-surfactant, antifoam agent, and the refractory fields of the sheaths, the cracks of the filaments were fixed by curing the slurry to 20 mm by copying paper due to coagulation. Oh-ulnta such vvalnuyu. Measurement of the raw strength of the suspensions are acids, as well as salts, rats after melting the model composition with acidic properties. As the coagulation samples cooled after calcination, complex compounds were formed on a PM-t tensile machine. nor, including coagulation products 25 Results of tests of hello, silicic acid and products of the exchange table. 4.: the reactions between the components of the suspension and the suspension and the method of treating Neuyeen, with a solution with acidic properties. coating layers improve the surface quality of the molds. . -, -. i ..,

Example. For an experimental test of the test, formulations and Formula cells were obtained and 6 re- and I-suspensions, which were: liquid glass-1, Suspension for forms, psmuchennmh b, ..:. lo, sodium tripolyphosphate, lactic acid melted models, including liquid; ,, -, that, sulfazole, ETS-40 and powdered quartz glass, acid, phosphorus-containing PC-2. 35 sob alkali metal, surfactant-a "-,;

The experimental test specimen was a thawed substance, an antifoam agent, and a refractory agent in the form of a common solution according to the method were filled with a filler, that is. The following components are taken: borna acid. In order to improve the quality of the surface, calcium and water. As a form of shell, it contains as a saturated aqueous lactic acid lactic acid, as a creator of sodium tripolyphosphate, a solution of sulfophosphorus salt of alkali metal-phanol with a density of 1130 ht / m3, aqueous la tripolyphosphate. sodium with the next solution of boric acid and chloride ratio of ingredients, May. %: chi. Liquid glass 13.7-21, St.

To check the composition for the manufacture of 45 Lactic acid, 3, the suspension shells were prepared suspension- aqueous solution of tripolyphosphate (Table 1). rub 20,0-28.3

Dg; checks on the processing of the fore-surface-active myoshells were made with the treatment-substance; . applying solutions (Table 2). 50 Antifoam 0 ,, $

Suspensions were made in a mixer. Refractory filler Else. with a capacity of 150 liters of alternately mixing- 2. The method of processing the forms obtained by using component in 15 minutes. The treatment of the produced models from the melting solutions was prepared in liquid glass binder and acid, tanks with a capacity of 40 liters. 55 hardener by impregnating them with hardening

A shell was manufactured using a treatment system with a solution that is characterized by covert solutions (Table 3). In order to improve the quality

The form-shells were dried in the air surface of the form-shell, impregnating the flow (speed 10 m / s at 28 ° C for a hardening acidic solution. First 45 mime; Drying the first layer after impregnation

form coat layer. immersing a block of models in a solution of compaction, May. %:

Borna acid2-4

Calcium chloride 10-30 Water Else, which is kept for 10-13 minutes.

Table 1

table 2

That blitz 3

Table A

Continuation of table 4

Claims (2)

Formula Z1, Suspension for molds prepared by 00 (. 'Smelting models, including liquid, glass, acid, an alkali metal phosphorus salt, surface ac-γ active substance, antifoam and refractory * filler, characterized in that. that, in order to improve the quality of the surface of the forming shell, it contains lactic acid as an acid, sodium tripolyphosphate as the phosphorus-containing alkali metal salt in the following ratio of ingredients, May. Liquid glass 13.7-21. # Lactic acid 0.87 * 1.3 / ^4> An aqueous solution of sodium tripolyphosphate 20.0-28.3 Surfactant 0.1- (73 ' Defoamer Q, 2-0, § Refractory Fill Else / 2. The method of processing forms. Obtained by lost wax models using a liquid-glass binder and an acid hardener by impregnating x with a hardening-acidic solution, preserving y-. '' '' the solution is the first layer of the mold. Immersing a block of models in a solution, May. %: Boric acid 2-4 Calcium Chloride 10-30 Water The rest, which is held for 10-15 minutes. Table 1 Composition Ingredients fermobolo ¹ mzaochny acid (Ki. wt.% Sulfanol (Surfactant) Dust quartz Liquid glass Grazed aqueous solution of sodium tripolyphosphate Antifoam agent 1 56.6 21.9 20.0 0.87 0.2 0.4 2 56.7 17.6 24.0 1,1 • 0.2 0.4 3 56.1 13.7 28.3 1.3 0.2 0.4 Way table 2 Ingredients for processing shapers, wt.% __ Water Boric acid Calcium chloride 88.0 2.0 10.0 77.0 • 3.0 20,0 66.5 3,5 30,0 76.0 4.0 20,0 That blitz 3 Composition for Methods for the manufacture of molds cooking for- 1 . 2 3 4 shell 1 eleven 12 2 20 2 22 2 24 2 25 3 thirty 31 Table 4 Shaping parameters. GF composition / Strength in cheese Strength after calcination, The specific length of the cracks, cm / cm ² Specific washout area? - Gf method condition, MPa MPa my surface, cm ² / cm ² 1/1. 14.0 19 1 0 0 1/2 15.5 13.2 0 0 2/1 12.0 10.0 0 0 2/2 15.3 12.8 0 0 2/3 15.0 13,2 0 0 Continuation of tzbl, 4 ί Parameters of f-zrmoo I Shell, GF composition / GF method Strength in the wet state, MPa Strength after calcination, MPa The specific length of the cracks, cm / cm ² The specific area of the eroded surface, cm * / cm ² 2/4 15.5 13.0 0 0 3/2 16.3 14.0 0 0 3/3 16.8 14.2 0 0