RU2147524C1 - Method of manufacturing objects - Google Patents

Abstract

FIELD: abrasive materials. SUBSTANCE: prior to be coated, object is treated with aqueous suspension of finely dispersed diamond-like carbon cluster in aqueous sulfuric or hydrochloric acid solution and then washed out with distilled water. EFFECT: reduced expenses. 3 cl, 1 tbl

Description

 The invention relates to a method for manufacturing products, in particular, decorative fittings, jewelry, watches, tools, etc.

 A known method of manufacturing products, which consists in the formation of a workpiece and the subsequent application of a coating of electrolyte suspension on its surface, including ultrafine diamond-like carbon clusters (see Shebalin A.I., Gubarevich V.D., Besedin V.I., Privalko Yu. N. About composite diamond-chrome coating. Explosion, impact, protection., 1987, issue 17, pp. 111-112 - analogue and prototype).

 In the known method of manufacturing products, it is not taken into account that the presence on the surface of particles of ultrafine diamond-like carbon clusters (UDDs) of chemical groups of mainly acidic nature determines the specific behavior of the particles of the dispersed phase in electrolytes with different pH values. So, in an acidic medium (pH <7), which is characterized by most electrolytes of chromium plating, nickel plating, and some others, UDD particles acquire a negative charge, which impedes their operability on the surface of the cathode, which also has a negative charge. As a result, the inclusion of particles in the coating composition is negligible. Conversely, in alkaline electrolytes (pH> 7), the surface nature of UDD particles contributes to their efficiency at the cathode.

 However, in this case, it is necessary to maintain the state of the surface of carbon particles (by analogy with cations) in the H-form. At the same time, analysis of industrial batches of UDD product available on the market shows that the product is mainly in the so-called "salt form".

 The technical result of this method is to increase the operational characteristics of the product when using less expensive product - UDD.

 This is achieved by the fact that before applying the coating, the main processing of an aqueous suspension of an ultrafine diamond-like carbon cluster in an aqueous solution of sulfuric or hydrochloric acid is carried out, followed by washing from acids in distilled water and additional treatment with a cationic substance to restore the bulk capacity and recharge the surface of the particles in the electrolyte.

 As a cationic substance, substances with tertiary or quaternary ammonium bases are used.

 Electrolytes based on hexavalent chromium, nickel, iron, gold and its alloys with cobalt, nickel, silver and copper, and copper are used as the suspension electrolyte.

 The essence of the method of manufacturing products is illustrated by the following examples.

 Formed blanks, for example, in the form of cylinders made of steel ШХ15 with hardness HV = 8.5 + 0.2 GPa. They were coated with a thickness of at least 50 μm from various electrolytes, including those containing ultrafine diamond-like carbon clusters (UDDs).

 Moreover, before applying the coating, the main processing of a suspension of an ultrafine diamond-like carbon cluster in an aqueous solution of sulfuric or hydrochloric acid was carried out, followed by washing from acids in distilled water and an additional treatment with a cationic substance to restore the volumetric capacity and recharge of the surface of the particles in the electrolyte; tertiary or quaternary ammonium bases.

 As the electrolyte, electrolytes based on hexavalent chromium, nickel, iron, gold and copper were used.

The wear resistance of the coatings was determined on the installation that implements friction on hardened steel without lubrication according to the "cylinder with intersecting axes" scheme. Wear resistance was determined as the reciprocal of the volume of worn material at a fixed test time (the length of the friction path) and the load on the friction pair (for various types of coatings, see the Table, the absolute load on the friction pair was: for chromium, iron - 15H, for nickel - 10H, for copper and gold - 5H). Sliding speed - 0.78 m / s, friction path length - 140 m, counterbody - X12M steel with HRC _e = 60 ± 1, R _a = 0.25 - 0.32 μm. The microhardness of the coatings was determined using a PMT-3 device at a load of 100 g and 50 g.

 As a result, it was found that the products obtained by the described method have increased wear resistance, and therefore, high quality.

In another example, we apply a protective and decorative coating of 985 gold-cobalt alloy on the case of men's watches made of LS59-1 brass with a thickness of 5 μm instead of the standard coating of an electrolyte composition: gold in the form of a cyanide complex of 6.5 g / l, cobalt in the form of sulfate salts of 1 g / l, potassium citric acid trisubstituted 2 x water 60 g / l, trilon-A- 3 g / l of the bright-forming additive "Limeda 3C-12" and UDA _processed. = 10 g / l (an electrolyte of the same composition was used as a standard electrolyte, but with an UDD _{outcome of} 10 g / l), the temperature of the electrolyte was 40 ^o C, the current density was 0.6 a / dm ² , and pH 4.5.

 Tests of wear resistance of coatings in a drum-type installation with an abrasive in the form of cylindrical granules of rubber with glass ⌀ 8 mm, length 10 mm (inspection of samples every 10 min). An additional check of the exposure of the base (brass) is carried out using a 10% solution of chlorinated copper (for reddening the base). Visual inspection with a MBS-2 microscope at 12x magnification.

 The tests were continued until the base was exposed at the sharp corners of the legs of the watch cases.

The test results showed a 1.7-fold increase in the wear resistance of the coating with the treated cluster compared to the initial cluster. The wear resistance of the coating with the initial cluster is 2 times higher than the wear resistance of the gold-cobalt coating without UDD. In this case, the hardness of the coating increases from 2.5 GPa (UDD _out ) to 3.2 GPa (UDD _process ).

 Thus, the invention improves the performance of products.

Industrial applicability
The invention can be used in the manufacture of decorative accessories, jewelry, watches, tools, etc.

Claims (3)

 1. A method of manufacturing products, which consists in the formation of a preform and the subsequent application of a coating of an electrolyte suspension comprising ultrafine diamond-like carbon clusters on its surface, characterized in that before applying the coating, the aqueous suspension of an ultrafine diamond-like carbon cluster in an aqueous solution of sulfur or hydrochloric is mainly treated acids followed by washing from acids in distilled water and additional treatment with a cationic substance to restore Nia volumetric capacity and recharging the surface of the particles in the electrolyte.  2. The method according to claim 1, characterized in that as a cationic substance using substances with tertiary or quaternary ammonium bases.  3. The method according to claims 1 and 2, characterized in that electrolytes based on hexavalent chromium, nickel, iron, gold and its alloys with cobalt, nickel, silver and copper and copper are used as the electrolyte suspension.

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