SU865980A1 - Solution for vibroabrasive cleaning of zinc and its alloys - Google Patents

Description

The invention relates to the means of chemical-mechanical processing of metals and alloys, in particular, to solutions for the vibroabrasive grinding of zinc and its alloys. A known aqueous solution is used in vibroabrasive grinding of parts made of zinc alloys, which contains a chromium in an amount of 3 g / l and a surfactant OP-7 or SP-10 in an amount of 5–7 g / l. However, the process of grinding parts in such a solution is long — 6–10 hours, depending on the initial state of the surface of the workpiece. In addition, the use of chromicum leads to the fact that the waste of the working solution that is subject to discharge as wastewater contains chromium ions, the concentrations of which exceed the maximum permissible standards of industrial sanitation. This requires additional wastewater treatment. A known solution for the vibration treatment of zinc and its alloys, containing oleic acid, chromium peak, caustic potash, calcined soda, triethanol, nitrobenzene, carboxymethylcellulose, sulfonol, and water 2 J. The disadvantage of this solution is low purification efficiency. The closest to the proposed is an aqueous solution used for the chemical treatment of ferrous and non-ferrous metals and their alloys during vibroabrasive cleaning and polishing (grinding), which contains the reaction product of polyoxyethylene alkylphenol (surfactant) with phosphoric acid in amounts corresponding to the ratio of RdOy and alkylphenol from 1: 3 to 3: 4 fSj. The disadvantage of this solution is also its relatively low effectiveness of the effect on the workpieces made of zinc and its alloys, as a result of which the vibration grinding process with the use of such a solution lasts 3-5 hours at temperatures of about 90-100 seconds. The purpose of the invention is to increase the productivity of the process. The goal is achieved by the fact that the solution containing phosphoric acid is a surface-active substance and water, additionally contains aluminum nitrate, aluminum sulfate, three-chloride iron and tropeoline 00 free acid and as a surface-active substance pyridinebetaine (betanap) in the following the ratio of components, wt.%: Phosphoric acid (unit weight 1.6) 4.7-5.6 Aluminum nitrate1.0-2, -5 Aluminum sulphate0.1-0.3 Tropeolin 00 free acid 0.02-0 , 05. Trichloride iron0,03-0,07 Betanal 0,01-0,015 WaterOstal Phosphorus acid is the main polishing agent, the active influence of which on the surface of the metal being processed is due to a number of reactions that lead to the dissolution of the metal. At the beginning of processing, when the concentration of phosphoric acid is sufficiently high, primary zinc phosphates are formed that deliver the basis of DAM 4-1 alloys DAM 10-5, DAM 9-1.5), which are well soluble in water and do not interfere with the further dissolution of the metal surface layer during vibro-processing. A decrease in concentration as the solution depletes over time causes the formation of secondary phosphates ZnHPO — labor soluble in water, and then tertiary phosphates Zn (PO), |, are completely n soluble, deposited on the surface metal in the form of a solid, durable film, dissolution is slowed down, its minimization of the activity of the action of phosphoric acid and thrombide 1, which reduces the performance of vibration treatment. In addition, with a decrease in concentration, the pH of the solution rises, which contributes to the initial hydrolysis of primary phosphates, the rate of which increases with a further 4 increase, and as a result, the film formed on the methane is additionally strengthened. In order to prevent undesired hydrolysis and maintain a certain acidity of the medium during vibro-processing, tropeolin 00 free acid, which is an activator, is introduced into the solution, maintaining the dissolution of the metal at the required rate at the given pH values. The ultimate goal of vibro-processing of parts made of zinc alloys in chemically active solutions is to obtain a surface microrelief characterized by a minimum roughness corresponding to the 9th class (the achievement of the roughness class is due to the requirements imposed on the metal surface). To prevent the corrosive effects of the acidic environment (the occurrence of rasters), Pe ions and salts like AE (NO) a, FeCe ,, Ae, (50d) are introduced into the solution. The nonionic chemically-active substance, pyridinobetaine (betaial), is a surfactant in solution, the composition of which is determined by the structural formula I 0-CtO and corresponds to MRTU 6-14-53 68. Being a surface-active substance in vibro-processing, The proposed concrete solution is also a wetting and washing agent, which eliminates the preliminary degreasing of parts before vibration treatment, thus simplifying the technology of using the solution. In this case, the presence of betanal, in comparison with other surfactants, retains the natural color of the metal surface, which in its absence during vibro-processing in a solution of the proposed composition becomes dark. Thus, the selective effect of each component of the solution when vibro-processing parts from zinc and its alloys is that it acts as a grinding reagent, tropeolin 00 free acid, as a buffer reagent and activating AE torus, Fe acting as pass N0 and Ct - as activators, syvators , ,, 50 - as a regulator of the activating effect of ions CC7 e betanal of surface-active wetting, washing and brightening agent. As a result of the complex effect of these com ponents on the metal in the region of optimal concentrations, not only the process is significantly intensified due to the reduction of the vibration treatment time, but it also succeeds in obtaining the required surface microroughness corresponding to a high grade, without corrosive damage to the microrelief. The solution is prepared by mixing these components in water. In this case, the mixture is not heated. The solution is tested under laboratory conditions, for which three mixtures are prepared (see Table 1), in each of which, as a solid filler, use is made of the beat of KCh-6 sharpening wheels, HT-HT granulation of 25-30 mm. 10 l of a solution with a filler are poured into an I-shaped reservoir with a capacity of 120 l and the DAM-4-1 zinc alloy parts are processed by it. The initial roughness of the surfaces of the parts corresponds to a RQ of 2.36-2.49 µm, 5 kg. Vibration grinding is performed with an oscillation frequency of 2050 count / min with amplitude 1.5-2.0 mm. Machine processing time 60 min.

Table 1 The results are shown in Table. 1, in table. 2 shows the comparative results of treatment in different solutions. Good surface quality is also obtained by vibro-abrasive grinding of the cast ZAM-4, -1V, TsAM4-10, TsAM10-5 and TsAM9-1.5 zinc alloy parts etched under etching. Thus, the proposed solution allows, without changing the working medium, to obtain the required class of cleanliness of the treated surface {9th class). At the proposed concentrations, the solution does not cause corrosion of the parts during processing. The maximum machine time for vibroabrasive grinding of each batch of parts is 60 minutes, which several times increases the productivity of the machining process. In addition, the solution is simple to prepare, it does not require heating and can be obtained by simply mixing the necessary components. Waste from the working solution discharged as wastewater does not contain any environmentally hazardous concentrations of chemical reagents and therefore does not require cleaning before discharge. The results of vibroabrasive pshifovany details of the alloy TSAM-4 in the proposed solution with different content of chemically active components are presented in table. one.

Phosphoric acid

Aluminum nitrate

Aluminum Sulphate

Vetanal Tropeolin 00

Traces of mechanical surface preparation (mechanical defects) are completely removed, corrosion damage

not

is free

0.02 acid

Trichloride

0.03 iron Else

2.36

Water

Phosphorus

5.2 acid

Nitrate 1.5 aluminum

Sulphate

0.2 aluminum 0.012

Betanal

Tropeolin 00 is free

0.03 acid

Trichloride

0.05 iron

2.49

Water Rest

osforna

5.6 acid

zinc acid 2.0 luminescent

fermented

0.3 aluminum 0.015

etanal

Tropeolin 00

is free

0.05

acid

Trichloride

0.07 iron

2.46

Water Rest

Comparative results of vibroabrasive grinding of details from the alloy. Continuation of table. one

0.23

66.73

0.21

67.87

Traces of mechanical surface preparation (mechanical defects) are completely removed, corrosion damage

not

66.71

0.22

VA PAM 4-1 in the proposed and known solutions are given in table. 2

R e for a gaemy

Phosphoric acid 5.2

Nitrate

Alkminium1,5

Sulfate 1

aluminum 0,2

Tropeolin 00

is free

acid0.03

Trekhloristoe

iron0.05

Betamal 0.012

WaterEverything

famous p

Chrompik 3 g / l

OP-76 g / l

famous p31

Phosphoric acid in terms of

1.0

0.21

2.20

66.5

6.5

2.00

2.17

Claims (3)

Invention Formula The solution for vibroabrasive cleaning of zinc and its alloys, containing phosphoric acid surfactant and water, characterized in that, in order to increase the productivity of the process, it additionally contains aluminum nitrate, aluminum sulphate, tropeolin 00 free acid, three-porous iron and as Surfactant pyridinobetaine (betanal) in the following ratio of components, wt.%: Phosphoric acid (beats weight 1,6) 4,, 6 Nitrate aluminum1.0-2.5 0.1-0.3 o0, 02-0.05 0.03-0.07 0.01-0.015 Rest Information sources, taken into account during the examination 1. Volumetric vibration treatment, ENIIMS, 1970, p. 53. 2. USSR author's certificate number 567738, cl. From 09 to 3/14, 1974. 3. US patent No. 3932243, cl. 156-20, 1976.