FI79721C - Method of applying a durable coating to a cutting tool of a carbonaceous material - Google Patents

Description

1 79721

A method of forming a wear-resistant coating on a cutting tool of carbonaceous material.

The present invention relates to metalworking, in particular, to cutting tools having a wear-resistant coating, and more particularly to a method of forming a wear-resistant coating on a cutting tool.

The method of forming a wear-resistant coating on a cutting tool is used for various cutting tools, such as drills, cutters, high-power milling cutters, made of a carbonaceous material such as high-speed steel and hard alloys.

Today, one way to increase the service life of a cutting tool with a wear-resistant coating 15 made of a refractory intrusion phase, such as TiC, TiN, is based on improving the performance of the wear-resistant coating itself, in particular its strength and durability. For this purpose, blending components are included in the pin-20 weaving compound, such as the commonly used transition metals of groups IVa-VIa, zirconium, molybdenum and tungsten.

A method of forming a wear-resistant coating on a cutting tool of carbonaceous material is known in the art. This wear-resistant coating contains crystals of tungsten carbide mixed in a certain ratio with crystals of titanium carbide, vanadium carbide, tantalum carbide and niobium carbide. The coating of mixed crystals is formed as a result of a reaction between transition metals such as titanium, vanadium, tantalum and niobium and mixtures thereof initially deposited on the surface of the cutting tool and between tungsten carbide incorporated in the material of the cutting tool body. This coating formation reaction from the mixed crystals occurs when the cutting tool is heated under vacuum or in an inert gas environment at a temperature of about 900 ° C.

2,79721 These metals are deposited on the surface of the cutting tool prior to the wear-resistant coating formation reaction by various methods, such as electroplating or vacuum deposition.

5 However, a wear-resistant coating can only be formed on a cutting tool made of hard alloys. For a cutting tool made of an alloy with a lower melting point compared to hard alloys, for example for high-speed steel, this process is unsuitable.

Furthermore, the number of wear-resistant coatings compositions thus produced is limited by the reactivity of tungsten carbide, which does not substantially react with Group I-III substances such as K, Na, Ba, Ca and Al.

A method for forming a wear-resistant coating on a cutting tool by condensing the material by ion bombardment is also known in the art, which allows the formation of a wear-resistant coating not only on hard alloys but also on tool materials with a lower melting point compared to hard alloys such as high speed steels. It includes the following functions: placing the cutting tool in a vacuum chamber, generating an arc discharge to vaporize the cathode material, supplying a bias to the cutting tool, heating the cutting tool to the steam-25 kneaded cathode material by ion bombardment, and That is, a wear-resistant coating is formed on the cutting tool that contains components present in the cathode material and the gas reagent. As is known, the cathode is conventionally made of transition metals of groups IVa-Vla or mixtures thereof, while the gas reagent is made of nitrogen, borane, methane. The wear-resistant coating thus formed, which is based on refractory intrusion phases such as TiC, TiN, has a high hardness and brittleness.

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In order to improve the performance of a wear-resistant coating, in particular to increase its use, it is necessary that it also have (in addition to hardness) plasticity and lubricating properties. These properties could be inherent in a coating containing, for example, Group I-III elements such as Te, Se, Ce, F, Os. However, it is essentially impossible to obtain Group I-III elements in the composition of the vaporized cathode material due to their physicochemical properties and the special features of the coating formation process by condensing the substance by ion bombardment.

Due to the low melting point of the elements of these groups, for example lithium has a melting point of 180 ° C and sodium has a melting point of 98 ° C.

During the evaporation of the cathode material, the cathode should be cooled with water. For this purpose, Group I elements that react with water to form alkalis and hydrogen cannot be included in the cathode material because it poses a risk of explosion.

It is further essential to make the cathode of a variety of materials that have negligible mutual solubility or form immiscible fluid solutions.

It is also substantially impossible to simultaneously evaporate by arc discharge the metals incorporated in the cathode composition and having ionization potentials which differ substantially from each other.

30 It is also not possible to manufacture cathodes or to incorporate liquid (mercury) and powdered (boron, phosphorus) components into the cathode material.

It is further undesirable to make cathodes from noble metals or rare earth metals such as platinum 35 and lanthanum.

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The present invention is directed to providing a method for producing a wear-resistant coating on a cutting tool of carbonaceous material by pretreatment of the cutting tool and its heating conditions by ion bombardment, which would increase the longevity of the wear-resistant coating and thus the life of the cutting tool.

This object is realized in a method of manufacturing a wear-resistant coating on a tool of carbonaceous material 10 by placing a cutting tool in a vacuum chamber, igniting an arc discharge to vaporize the cathode material, heating the cutting tool by ionizing according to the invention, before placing the cutting tool in a vacuum chamber, it is immersed in a saturated saline solution containing a cation of Na, K, Ag, Ca, Ga, Tl, La, Ce or Ta and / or an anion 20 containing B, Se, Te , S, Re, Ru, Os, Pt or W, is kept in this solution for 5-10 minutes at the temperature of the saturated brine and the solvent is evaporated until the salt has crystallized on the surface of the cutting tool, heating the cutting tool by bombarding h the ions of the vaporized cathode material are first provided to the decomposition temperature of the salt crystals, after which the arc discharge is turned off, the cutting tool is held at this temperature for 15-30 seconds, then the arc discharge is re-ignited and heating is continued until the vaporized cathode material has reached the carbide temperature.

This method of forming a wear-resistant coating on a cutting tool of carbonaceous material makes it possible to improve the service properties of the wear-resistant coating and to extend the service life of the cutting tool by at least 1.5 times. The increase in the life of the cutting tool 5,79721 is due to the formation of a lower layer of crystals mixed on its surface, some of which mix with the coating during its condensation, thus mixing and strengthening it while some of the crystals melt and soften and fill cavities due to surface roughness. During the use of the cutting tool, its durability is improved due to the improvement of the physico-chemical properties of the wear-resistant coating. Simultaneously with the improved hardness, the plasticity and friction-reducing properties of the coating are also improved due to the presence of components in the wear-resistant coating having plasticity as well as the presence of components having lubricating properties.

The present invention is further illustrated by explaining some specific examples which illustrate specific embodiments thereof.

The advantages of the present invention will become more apparent from the following specific examples of its applications.

The method of forming a wear-resistant coating on a cutting tool is as follows. First, a cutting tool is made of a carbonaceous material, such as high-speed steels, hard alloys.

The cutting tool is then placed in a saturated saline solution, for example an aqueous solution of borax, and held there for 5-10 minutes at the temperature of the saturated solution. This results in the deposition of hydrated salt ions on the surface of the cutting tool. A saturated solution of any salt may be used: conventional salts, complex salts or organometallic salts containing in its composition cations of the following substances; Na, K, Ag, Ca, Ga, Tl, La, Ce or Ta and / or an anion containing B, Se, Te, S, Re, Ru, Os, Pt or W. Both naturally occurring salts and salts can be used, prepared in the laboratory.

6 79721

Depending on the type of salt used, a suitable solvent is used: water or an organic solvent such as acetone, ethanol.

Saturated saline is prepared at the dissolution temperature of each of these 5 salts in a particular solvent.

The solution should be impregnated to ensure maximum deposition of salt ions on the surface of the cutting tool. When supersaturated solutions are used, the deposition process is prevented by the presence of their second phase, reducing the amount of ions that deposit on the surface of the cutting tool and disturb the uniformity of their distribution on the surface.

Keeping the cutting tool in the saturated saline solution is carried out at the dissolution temperature of each particular salt in order to maintain a constant concentration of ions in the solution and to prevent precipitation of the second phase from the solution. To maintain the solution at a constant temperature, it is heated, if necessary, in the usual manner.

The optimal holding time of the cutting tool in saline is determined experimentally. With holding times of less than 5 minutes, the amount of salt ions deposited on the surface of the cutting tool does not provide any significant prolonging effect on the life of the wear-resistant coating. Also, holding runs of more than 10 minutes will no longer achieve an additional extension in service life.

The solvent is then evaporated until the salt has crystallized on the surface of the cutting tool. Depending on the solvent used, it evaporates either naturally in air at ambient temperature or when heated to the crystallization temperature of the salt.

If the temperature at which crystallization of the salt from the solution is achieved is below the crystallization temperature, the resulting crystals contain excess water of crystal or residual solvent is present on the cutting tool surface, which is undesirable because the wear resistance

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If the crystallization temperature of the salt is above the crystallization temperature, the salt may partially decompose outside the chamber, also resulting in reduced tool durability.

The cutting tool is then placed in a vacuum chamber with the cathode positioned therein and containing at least one Group IVa-VIa transition metal to be included in the wear-resistant coating composition. Most commonly, this cathode is made of titanium or titanium-based alloys. Other cathodes may also be installed in the vacuum chamber, provided that other metals of the above groups should be included in the composition of the wear-resistant coating.

The chamber is then placed under vacuum and an arc discharge is ignited to ensure evaporation of the cathode material. A known bias voltage of 800-10,000 V is applied to the cutting tool and the heating of its surface is achieved by bombarding the vaporized cathode material with ions. Heating is provided in two stages: first -20 to the decomposition temperature of the salt crystals, which is controlled by a pyrometer. Once this temperature is reached, the arc discharge is turned off and the cutting tool is held for 15-30 seconds to break up the salt crystals into their components. With hold times of less than 15 seconds, the amount of salt disintegrated is insufficient to ensure an increased service life of the coating, while additional heating contributes to the melting and evaporation of the remaining amount of salt from the surface of the cutting tool.

With holding times of more than 30 seconds, the cutting tool begins to cool and the decomposition process of the salt crystals thus stops. The arc discharge 50 is then re-ignited and the heating of the cutting tool is continued to the carbidation temperature of the vaporized cathode material, which is also controlled by a pyrometer.

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The bias voltage applied to the tool is then reduced to a value that ensures condensation of the vaporized cathode material on the surface of the cutting tool. This bias voltage is known, it is changed in the range of 25-750 V. At the same time, 5 gas reagents are allowed to react in the vacuum chamber with the vaporized cathode material to form a wear-resistant coating. Nitrogen, methane, borane are used as the reacting gas. The gas reagent is fed into the vacuum chamber at a pressure of 5x10-5x10 mm Hg.

After the wear-resistant coating is formed to a predetermined strength determined by the gas reagent release time, its supply is stopped, the bias voltage is turned off from the cutting tool, the arc discharge is turned off, and the cutting tool is cooled in the chamber to room temperature.

For a better understanding of the present invention, some examples are provided below to illustrate certain embodiments thereof.

Example 1 A spiral drill is made of high-speed steel having the following compositions in the following percentages by weight: C - 0.85, Cr - 3.6, W - 6.0, V - 2.0, Mo - 5.0, Fe - the rest. Several drills cleaned of mechanical impurities and lubricants in a number of 10, 25 are placed in a vessel filled with tetraboric acid

With a saturated solution of the sodium salt of Na2B2O2 at a temperature of 30 ° C. The salt contains a Na + cation and a (B 2 O 2) anion including B. A solution saturated at this temperature is prepared by dissolving 3.7 g of borax in 100 g of water.

30 Water is used as a solvent. Several drills are kept in solution for 5 minutes at a solution temperature of 30 ° C. The drills are then placed in an oven at 60 ° C, i.e. the crystallization temperature of the borax from solution, are heated to this temperature and the solvent evaporates.

9,79721

The drills are then placed in the vacuum chamber of a unit of a known type to produce coatings by ion bombardment of the substance. The chamber is evacuated to a pressure of 5x10 mm Hg and a bias voltage of 1200 V is applied to the drill.

5 The arc discharge is ignited in the chamber and the titanium cathode evaporates. In this way, the surface of the drill is heated to a temperature of 400 ° C, i.e. to the decomposition temperature of borax, under Ti ion bombardment conditions known from the literature. The light-10 arc discharge is then turned off for 20 seconds. After this time, the arc discharge is re-ignited and the heating of the pores by ion bombardment is continued to a temperature of 520 ° C, i.e. the carbidization of titanium to a known temperature under ion bombardment. At this temperature, titanium-15 carbide is formed when titanium interacts with the carbon of the drill material, i.e., high-speed steel.

After reaching the carbide temperature of titanium, the bias bias voltage is reduced to 350 V and nitrogen is introduced into the chamber. In doing so, the pressure in the chamber is 3x10 mm Hg.

After nitrogen reacts with titanium, a wear-resistant titanium nitride coating with a thickness of 5 μm is formed on the surface of the drill. The nitrogen emission is then stopped, the arc discharge is turned off, the voltage from the tool is switched off and the tool is cooled in the chamber to room temperature.

25 Several 5 mm diameter strength tests were performed by drilling holes in steel of the following composition: C - 0.42-0.49% by weight, Fe - the rest, in the presence of a known cutting fluid and coolant with a vertical drilling machine under the following cutting conditions: speed v = 30 45 m / min, feed S = 0.18 mm / rev, drilling depth 1 = 3 d, where d is the diameter of the drill. Boredom criterion - drill spark. The average number of holes made with one drill is 390.

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Example 2

Several pores similar to those described above in connection with Example 1 are prepared and placed in a vessel filled with a saturated solution of potassium carbonate in CO 2 at 20 ° C. The salt contains the K + cation. To prepare a saturated solution, 113.5 g of salt are dissolved in 100 g of water. The drill is kept in solution for 7 minutes while maintaining the temperature at 20 ° C. The work-up is carried out as in Example 1 above except that the crystallization of the salt is carried out at 40 ° C and the heating of the drill surface by ion bombardment of vaporized cathode material in the first step is carried out at 400 ° C, i.e. potassium carbonate decomposition temperature under ion-15 bombardment. The arc discharge is then turned off for 15 seconds. The further steps of the method are performed as described in Example 1.

Drill durability tests are performed following the procedure described in Example 1. The average number of holes-20 made with one drill is 420.

Example 3

A series of drills similar to those described in Example 1 are prepared and placed in a vessel filled with a solution of sodium nitrate in NaNO 2 at a temperature of 20 ° C. The salt contains a Na + cation. To prepare a saturated solution, 46.8 g of salt are dissolved in 100 g of water. The drill is kept in this solution for 10 minutes while maintaining the temperature at 20 ° C. The further steps of the process are carried out as described above in Example 1 except that the crystallization of the salt is carried out at 30 ° C and the heating of the drill surface by ion bombardment of vaporized cathode material is carried out in the first step to 380 ° C, i.e. sodium nitrate decomposition The arc-35 discharge is then turned off for 25 seconds. Process 11,79721 is then performed as described above in Example 1. The batch strength tests are performed as in Example 1. The average number of holes made with one drill is 350.

Example 4 A series of drills similar to those described in Example 1 are prepared and placed in a vessel filled with a solution of lanthanum sulfate at a temperature of 20 ° C. The salt contains a La +++ cation and an (SO 4) - anion containing S. To prepare a saturated solution, 3.9 g of salt are dissolved in 100 g of acetone. The drill is kept in solution for 10 minutes.

The further steps of the process are performed as described in Example 1 above, except that the solvent is evaporated in a natural manner and the heating of the drill surface by vapor bombardment of the evaporated cathode material is performed in a first step to 450 ° C, i.e. salt decomposition temperature under ion bombardment. The arc discharge is then turned off for 25 seconds. Drill batch durability tests are performed as in Example 1. The average number of holes made in one drill is 300.

Example 5

The process is carried out as described in Example 4 except that cesium sulphate is used as the salt. Salt Ce2 (SO4) 3 contains a Ce +++ cation and a (SO2) anion, thus S. To prepare a saturated solution, 15 g of salt per 100 g of water at 20 ° C are used. The solvent is evaporated at a temperature of 30 ° C, and the heating of the drill surface by ion bombardment of the vaporized cathode material is performed in a first step to a temperature of 500 ° C.

The batch strength tests are performed as described in Example 1 above. The average number of holes made with one drill is 340.

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Example 6

The process is carried out following the procedure described in Example 4 above, except that tantalum chloride TaCl 2 is used as the salt. The salt contains the Ta +++ 5 cation. To prepare a saturated solution, 3.5 g of salt per 100 g of water at 70 ° C are used.

The solvent is evaporated at a temperature of 30 ° C and the heating of the drill surface by bombardment of the ions of the vaporized cathode material is performed in a first step to a temperature of 300 ° C. 10 Batch strength tests are performed as described in Example 1 above. Average number of holes made with one drill 346.

Example 7

The process is carried out as described in Example 4 except that sodium sulfide Na 2 S is used as the salt. The salt + - ^ contains a Na cation and an S anion. To prepare a saturated solution, 18.06 g of salt per 100 g of water at 20 ° C are used. The solvent is evaporated at a temperature of 50 ° C and the heating of the drill surface by ion bombardment of the vaporized cathode material is performed in a first step at a temperature of 150 ° C.

Drill batch durability tests are performed as described above in Example 1. Average number of holes made with one drill 352.

25 Example 8

The process is carried out as in Example 4, except that sodium telluride Na 2 Te is used as the salt. The salt contains a Na cation and a Te anion. To prepare a saturated solution, 15 g of salt per 100 g of water are used at a temperature of 20 ° C. The solvent is evaporated at 50 ° C

and heating in the first step is performed to a temperature of 200 ° C.

Drill batch durability tests are performed as described in Example 1. Average number of holes made with one drill 369.

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Example 9

The process is carried out as described in Example 4, except that sodium selenide Na 2 Se is used as the salt.

+ —— ^

The salt contains a Na cation and a Se anion. 13.2 g of salt per 100 g of water at 20 ° C are used to prepare the saturated solution. The salt is evaporated at a temperature of 50 ° C and the heating of the surface of the drill by ion bombardment of the vaporized cathode material is performed in the first step to a temperature of 230 ° C.

The batch strength tests are performed as described in Example 1 above. The average number of holes made with one drill is 345.

Example 10

The process is carried out as described in Example 4, except that potassium perrenate KReO 2 is used as the salt.

The salt contains a K + cation and a (ReO 2) anion including Re. To prepare a saturated solution, 6.34 g of salt per 100 g of water at 20 ° C are used. The solvent is evaporated at a temperature of 100 ° C and the drilling of the drill surface by ion bombardment of the vaporized cathode material is performed in a first step to a temperature of 250 ° C.

Drill batch strength tests are performed as described above in Example 1. The average number of holes made with one drill is 285.

25 Example 11

The process is carried out as described in Example 4 except that potassium hexacyanoruthenate käytetään ^ / Ru (CN) is used as the salt. The salt contains a K + cation and a / Ru (CN) g7 anion containing Ru. 30 g of salt per 100 g of water at 80 ° C are used to prepare the saturated solution. The solvent is evaporated at a temperature of 100 ° C and the heating of the drill surface by ion bombardment of the vaporized cathode material is performed in the first step to a temperature of 220 ° C.

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Drill batch durability tests are performed as described in Example 1 above. The average number of holes made with one drill is 310.

Example 12 The procedure is carried out as in Example 4 except that potassium hexacyano-osmate K4 / Ös (CN) ^ is used as the salt. The salt contains a K + cation and a / Os (CN) g7 anion including Os. To prepare a saturated solution, 22 g of salt per 100 g of water at 80 ° C are used. The salt is evaporated at a temperature of 100 ° C and the heating of the drill surface by ion bombardment of the vaporized cathode material is performed in a first step to a temperature of 240 ° C.

Drill batch durability tests are performed as shown in Example 1. The average number of holes made with one drill is 380.

Example 13

The process is carried out as described in Example 4, except that potassium tetracyanoplatinate 20 K 2 / Pt (CN 2 VJ) is used as the salt. The salt contains a K + cation and a / PtfCN)? To prepare a saturated solution, 18 g of salt per 100 g of acetone at 38 ° C are used. The solvent is evaporated in a natural manner and the heating of the drill surface by ion bombardment of the vaporized cathode material 25 is performed in the first step to a temperature of 200 ° C.

The batch strength tests are performed as described in Example 1 above. The average number of holes made with one drill is 334.

30 Example 14

The process is carried out as described in Example 4 except that the potassium thiocyanate KNCS is used as the salt.

The salt contains a K + cation and an NCS anion including S. 217 g of salt per 100 g of water at 20 ° C are used to prepare the saturated solution. The solvent is evaporated at a temperature of 30,79721 and the surface of the drill is heated to 120 ° C in a first step by bombarding the ions of the vaporized cathode material.

Drill batch durability tests are performed as described in Example 1. The average number of holes made with one drill is 395.

Example 15

The process is carried out as described in Example 4 except that lithium hexachloroplatinate 10 Li / Pt (Cl) g / is used as the salt. The salt contains a / Pt (Cl) anion

Pt. To prepare a saturated solution, 56 g of salt per 100 g of water are taken at 20 ° C. The solvent is evaporated in a natural manner and the heating of the drill surface by ion bombardment of the vaporized cathode material is performed in a first step to a temperature of 450 ° C.

Drill batch durability tests are performed as described above in Example 1. The average number of holes made with one drill is 257.

Example 16 The process is carried out as in Example 4 except that magnesium sulphate MgSO 4 is used as the salt. The salt contains a (SO 2) anion including S. 35.6 g of salt per 100 g of water at 20 ° C are used to prepare the saturated solution. The solvent is evaporated at a temperature of 70 ° C and the heating of the drill surface by ion bombardment of the vaporized cathode material is performed in a first step to a temperature of 250 ° C.

Drill batch durability tests are performed as described in Example 1. The average number of holes made in one drill is 310.

Example 17

The process is carried out as described in Example 4 except that beryllium sulphate BeSO 4 is used as the salt. The salt contains a (SO 2) anion including S. To prepare the saturated solution 35, 40 g of salt per 100 g of water are used per 79721 at 20 ° C. The solvent is evaporated at a temperature of 30 ° C, and the heating of the drill surface by ion bombardment of the vaporized cathode material is performed in the first step to a temperature of 340 °.

5 Drill batch durability tests are performed as described in Example 1. The average number of holes made with one drill is 346.

Example 18

A batch of drills similar to those described in Example 1 above is prepared and placed in a vessel filled with a Ga (SO) saturated solution of gallium sulfate at a temperature of 20 ° C.

1 H 0 3 +

The salt contains a Ga cation and an SO 2 anion including S. To prepare a saturated solution, 15 g of salt per 100 g are used. The drills are kept in solution for 10 minutes while maintaining the solution at a temperature of 20 ° C. The process is then performed as described in Example 1 except that the salt crystallization is performed at 40 ° C and the heating of the drill surface by ion bombardment of the vaporized cathode material 20 is performed in the first step to 450 ° C, i.e. to the salt decomposition temperature under ion bombardment.

Drill strength tests are performed as described in Example 1. The average number of holes made with one drill is 400.

Example 19

A batch of drills similar to those described in Example 1 is prepared and placed in a vessel filled with a saturated solution of sodium tungstate Na 2 WO 4 at 20 ° C. The salt contains a Na + cation and a (WO 2) anion including W. To prepare a saturated solution, 72 g of salt per 100 g of water are used. The drill is kept in solution for 10 minutes while maintaining the solution 35 at 20 ° C. The process is then continued in much the same manner as described in Example 1 except that the salt crystallization is performed at 80 ° C and the drill surface heating by ion bombardment of the vaporized cathode material is performed in the first step 5 to 200 ° C and the arc discharge is turned off for 10 seconds.

Drill batch durability tests are performed as described in Example 1. The average number of holes made with one drill is 340.

1 0 Example 20

A batch of cutting plates is made of 10 hard alloys with the following composition: titanium carbide TiC - 15% by weight, cobalt Co - 6% by weight, tungsten carbide - WC - the rest. The cleaned plates are placed in 15 vessels filled with a saturated solution of calcium nitrate in Ca 2 SO 4 at a temperature of 20 ° C. The salt contains a Ca ++ cation. The saturated solution is obtained by dissolving 121 g of salt in 100 g of water. The plate is kept in solution for 5 minutes while maintaining the temperature of the solution at 20 ° C.

After keeping in solution, the plates are placed in an oven and the solvent is evaporated at 35 ° C. The sheets are then transferred to a vacuum chamber in a unit for effecting coating by condensation of the substance by ion bombardment. The chamber is pressurized to 5x10 mm Hg and a bias voltage of 1500 V is applied to the plates. The arc discharge is ignited in the chamber and a cathode made of titanium is vaporized. In this way, the surface of the plate is heated by bombardment of titanium ions to a temperature of 100 ° C, i.e. to the decomposition temperature of the salt under ion bombardment conditions. Thereafter, the arc discharge is turned off for 20 seconds. It is then re-ignited and the plates are continued to be heated to 650 ° C, i.e. to the temperature of formation of titanium carbide with the titanium interacting with the carbon of the plate material. The bias voltage is then reduced to 300 V and nitrogen is introduced into the chamber at a pressure of 18,79721 2x10 2 mm Hg. After nitrogen reacts with titanium, a 6 μm thick wear-resistant titanium nitride coating is formed on the surface of the cutting plates. The nitrogen discharge is then stopped, the arc discharge is switched off, the voltage is cut off from the plates, which are then cooled in the chamber to room temperature. The strength tests of the plates are carried out by turning steel of the following composition: C - 0,36 to 0,45% by weight, Fe - the rest, under the following cutting conditions: speed v - 160 m / min, feed S - 0,3 mm / revolution, cutting-10 depth 1 - 1 mm.

The durability of the plates is determined by the number of workpieces machined on each plate until it wears out. The average number of machined workpieces per plate is 35.

15 Example 21

A batch of cutting discs similar to those described in Example 20 is prepared and placed in a vessel filled with a saturated solution of thallium nitrate T1 (NO -.) _, + + + ^ 3, which salt contains the T1 cation and has a temperature of 20 ° C. . To prepare the solution, 9.55 g of salt are used per 100 g of water. The drills are kept in solution for 7 minutes while maintaining the solution at a temperature of 20 ° C. The process is then continued as shown in Example 20 except that the crystallization of the salt is performed at 25 ° C and the surface of the plates is heated in the first step to 200 ° C, the arc discharge being turned off for 15 seconds.

Durability tests are performed following the procedure of Example 20. The average number of 30 workpieces machined on one plate is 40.

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Example 22

A batch of cutting discs similar to those described in Example 20 is prepared and placed in a vessel filled with a saturated solution of silver acetate AgC 2 H 3 ° 3 at 20 ° C for 10 minutes. The salt contains an Ag + cation. 1.04 g of salt per 100 g of water are used to prepare the solution. The process is then continued as described in Example 20 above except that the crystallization of the salt is performed at 50 ° C and the heating in the first step is performed at 120 ° C, i.e., the decomposition temperature of the salt under ion bombardment.

The plate batch strength tests are performed as described above in Example 20. The average number of workpieces machined on one plate 15 is 38.

Claims (1)

Claim: A method of making a wear-resistant coating on a cutting tool made of a carbonaceous material, comprising placing the cutting tool in a vacuum chamber, igniting an arc discharge therein to vaporize the cathodic material, interacting with a gas reagent released into a vacuum chamber, characterized in that before placing the cutting tool in the vacuum chamber it is immersed in a saturated salt solution containing a cation of Na, K, Ag, Ca, Ga, T1, La, Ce or 15 Ta and / or an anion containing substance B, Se, Te, S, Re, Ru, Os, Pt or W, is kept there for 5-10 minutes at the temperature of the saturated solution and the solvent is evaporated until the salt crystallizes on the surface of the cutting tool, Ion bombardment of the vaporized cathode material is first performed to the salt decomposition temperature, after which the arc discharge is turned off, the cutting tool is held at this temperature for 15-30 seconds, then the arc discharge is re-ignited and heating is continued to the carbide material. 21 79721 Förfarande för päförande av en slitstark belägg-Ning pä ett scärverktyg utför av ett kolhaltigt mate-5 rial, vilket förfarande bestär i att man dels placerar skärverktyget inuti en vakuumkammare, dels tänder en 1jusbägurddding in scattering of the cathode-ray tube by means of a detonating cathode material 10 and a second-hand stacking of the cathodic material of the cathode-ray tube by means of a hot-air chamber in the field of gas reactants detta in i en mättad lösning 15 av ett sait som innehäller resp. Na-, K-, Ag-, Ca-, Ga-, Tl-, La-, Ce-, ell Ta-cation och / eller resp. E, Se, Te, S, Re, Ru, Os, Pt eller W innehällande anjon, där det hälles kvar under 5-10 min at a temperature which is too high with a low salt temperature, and at least 20 lysningsmedlet tills saltet kristalliseras pä skärverkty -with yta, och att man upphettar skärverktyget medelst bombardering med joner av det avdunstade katodmaterialet först account saltets sönderdelningstemperatur, vid vilken skärverktyget efter släckning av bägurladdningen hälles 25 kvar under 15-30 s, och sedan, eh sedan, eh sedan, eh sedan the cathode material temperature of the cathode material is determined.