JPS5932541B2 - Relatively low wear-resistant metal article coated with refractory metal and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to protective coatings, particularly anti-wear coatings applied to surfaces made of metals, alloys and metal-containing substrates and similar materials.
It relates to discontinuous coatings of refractory metal particles, such as heat-resistant or chemical-resistant or similar materials.

An object of the present invention is to provide an inexpensive and economical method for applying a refractory metal to the surface of a base metal at low temperatures, including room temperature. Another object of the present invention is to apply refractory metals to the surfaces of various metals or metal-containing materials as coatings of individually separated refractory metal particles to provide smooth, low-friction, wear-resistant, chemical-resistant, A method of making a rustproof or similar protective coating and a coated article are provided.

Method of the Invention The present invention provides a method of applying a refractory or protective metal having a melting point of at least 1490° C. to various metals, alloys or metal-containing substrates in combination with an electrolyte and at least in part located between the refractory metal particles and the substrate metal. This is the only finding that can be deposited on.

In particular, these refractory or protective metals which can be used are the following metals in powder or granular form and all alloys of combinations of these metals: shaped or spherical or acicular or
It is one of the dendritic forms and the practical small size is generally 0.01 micrometer to 1 m7! Preferably it is L.

The substrate metals on which the refractory metal may be deposited are metals such as aluminum, iron, chromium, cobalt, copper, nickel, magnesium, tin, titanium or alloys of these metals, including steel, cast iron, brass, bronze. , braze or other suitable base metal.

Near-Surface area of the substrate
In order to carry out the deposition of particulate refractory metal in n), it is also necessary that there be a finely dispersed electrolyte which is to be located at least partially between the particulate refractory metal and the base metal.
In the present invention, "Near-Surface area"
"reglOn)" refers to an area that includes both the base metal and the refractory metal cladding layer that has been partially replaced or infiltrated with a refractory metal.

Electrolytes used in the present invention include mineral acids such as hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, perchloric acid, silica acid, etc., acid anhydrides such as arsenic trioxide and chromium trioxide, tartaric acid, malonic acid and the like. It has been found that acids consisting of organic acids such as:

Useful basic electrolytes are alkali and alkaline earth hydroxides such as sodium, potassium, lithium, calcium, magnesium, and the like. Also, alkali halide salts, especially alkali and alkaline earth salts of the aforementioned acids such as chlorides, chlorates, fluorides, nitrates, sulfates, phosphates, carbonates, etc. and sulfates, phosphoric acids, etc. salt,
Refractory metals that form salts such as nitrates, carbonates, chromates, molybdates, tungstates, etc., or metals currently used as part of electrolytes that are one of the metals listed above as base metals. Any one metal salt is also useful as an electrolyte. Compounds such as ammonium thiocyanate, potassium thiocyanate, zinc sulfate, ammonium carbonate, ammonium sulfate, potassium sulfate, sodium sulfide, sodium carbonate, potassium cyanide, calcium nitrate, potassium chloride and calcium chloride are also useful as electrolytes.

The electrolyte can generally be any acid, base or salt, but
It must dissociate in the presence of moisture, ie it must be able to conduct an electric current and have a sufficient degree or percentage of dissociation or more precisely a sufficiently high equivalent conductivity ratio.

For the purposes of this invention, this conductivity ratio is measured as the ratio between the equivalent conductivity at a dilution of 19 m equivalents/101 water and the equivalent conductivity at infinite dilution, and the temperature is 2.
5° C. (see “Physical Chemistry of Electrolytes” by Harnd and Owen, Reinhold Publishers, 1958).

Electrolytes useful in the present invention are those having a conductivity ratio of about 0.13 to 0.93, preferably 0.60 or greater. The following are approximate values of some acids, bases and salts and their corresponding conductivity ratios that meet the requirements of the present invention:) Since dissociation is a criterion for the selection of electrolyte in the method of the present invention, It was concluded that the dissociation ability of the electrolyte is greater, and the reaction of the present invention can be carried out more effectively.

This assumption allows for more complete ionization of the electrolyte and serves the purpose of the method of the invention more effectively. As far as the method of the invention is concerned, it is not necessary to apply an electric current to deposit refractory or protective metals in and on its surfaces, but since the method of the invention is considered fundamentally electrolytic, the application of an electric current is not necessary. influence and assist the method of the invention. Applied current is not a requirement for the method of the invention since the internally generated electrolytic current is of sufficient strength on a very small scale to obtain the results of the invention. In order to achieve the electrochemical reaction that deposits the refractory metal onto the substrate material, intimate integration between the particulate refractory metal, the electrolyte, and the substrate material is believed to occur.

In this regard, it is recognized in the case of solid electrolytes that the exact combined particle size of the electrolyte and refractory metal is not critical or important since this size is primarily due to the size of the normally harder refractory metal. It was done. The electrolyte particles are preferably pulverized to a size of 10@-3 micrometers to about 1 mm.sup.1, preferably 10 to 100 times smaller than the coexisting refractory metal particles when applied to the base metal. At the start of a reaction in which a portion of the base metal is believed to be exchanged with the refractory metal, it is important that the refractory metal is partially ionized and undergoes an exchange reaction with the base metal.

Refractory metal/solution with ion concentration of 1 to 60,000 l
It was recognized that this should be done. Preferably, the ion concentration range is between 1,000 and 15,000 η refractory metal ions/l solution. After exchange reaction with the base metal, the refractory metal ions are believed to provide a site for particles of refractory metal to precipitate.

These reactions are thought to occur only on a microscopic scale. In order to generate at least a sufficient amount of refractory metal ions for the desired reaction, it is important that at least a portion of the surface of the refractory metal particles to be deposited has a nascent surface. Although not fully explained, this fresh surface produces the requisite concentration of refractory metal ions for a sufficient period of time that the electrolyte and any moisture present can combine with the refractory metal.

Although all refractory metals are normally insoluble in the moisture present, nevertheless sufficient concentrations of ions required for this invention are generated from the surface of the refractory metal generator in the presence of an electrolyte and sufficient moisture. be done. The required generator surface is easily prepared by mechanical action such as abrasion or other mixing, abrasion, or by the chemical action of an electrolyte or pond reactive material that creates a generator surface on the refractory metal particles. can be generated. The amount of mechanical or chemical action that produces the generator surface is not critical as the generator surface is produced by such mixing action.

The refractory metal ion is removed from the surface of this generator for 1 to 3 minutes.
generated at time intervals of preferably 1 to 20 hours on day 0,
This time is dependent on the moisture, temperature and solubility of the refractory metal. Therefore, this time is not critical. It is only important that the requisite concentration of refractory metal ions be present and that a generator surface be created, so that particulate refractory metal is deposited in the surface area of the base metal. Providing a close relationship between the electrolyte and the particulate refractory metal and placing the electrolyte between the surface of the base metal and the refractory metal results in more generator surface being exposed on the refractory metal particles. Similarly, various other methods are possible.

If the refractory metal is in the physical state of a dry powder under atmospheric conditions and the electrolyte is also in a fairly dry granular form, an intimate mixture can be obtained by mixing the two powders together. The quantitative range of refractory metal is 99-50% by weight of the dry mixture of refractory metal and electrolyte, preferably 96-66% by weight? It is. Is the electrolyte 1-50% by weight of the above dry weight mixture? , preferably 4 to 34 weight? is within the range of In order to enhance the electrochemical action of the present invention, 1 to 10% of the total mixture of refractory metal and electrolyte may be added with a component or compound that acts as a reagent to avoid electrochemical polarization action. can be appropriately blended into the particulate refractory metal and the electrolyte. Examples of such non-polarizing compounds or components are MrlO2, platinum group metal powders, CUOlHgOl ionizable iron or halides, tin salts such as sulfates, nitrates, etc. and activated carbon. The thickness of the electrolyte coating on the refractory particles should be as continuous and homogeneous as possible and may be from a molecular film to 25 micrometers or up to 1 mm thick.

Although most of the refractory metal surface should be coated, a small coating as low as about 10% may also be employed. The mixing or grinding to produce either or both the surface of the generator on the refractory metal particles and the coating of the refractory metal particles with the electrolyte powder is such that both the electrolyte and the refractory metal powder contain small amounts or unobservable moisture. It was acknowledged that this can occur when the weather is quite dry.

This mixing time is generally about 30 minutes to 30 days. However, sufficient moisture must be present to create refractory metal ions, and these ions are not formed. If either the refractory metal and/or the electrolyte are dry under atmospheric conditions, this mixture can be used to remove about 0% of the total mixture before processing the base metal.
．． Water should be present in the refractory metal-electrolyte mixture in an amount of 5-60% by weight.

The amount of water is preferably 1 to 40% by weight. The advantages of the invention can also be achieved by intimate moisture addition of the electrolyte and refractory metal as a paste, slurry or solution in a liquid medium such as water.

A sufficient amount of water in the mixture can be determined if the electrolyte exhibits an electrical resistance value of less than about 106 ohm-cm. If the electrolyte is a liquid, the addition of a liquid medium is not necessary, but particularly strong mineral acids are preferred. The presence of some water in the refractory metal and electrolyte mixture is important to create an ion concentration of the protective metal and to allow reactivity of the electrolyte that is highly compatible with ion exchange by the base metal.

This single mixing or combined mixing and aging step, which takes place from 10 minutes to 30 days, can replace the time required to obtain a concentration of refractory metal ions on the surface of the generator and refractory metal ions. If the concentration is not found to be sufficient, remixing and/or another aging period of usually 1 to 30 days is required.

The actual concentration of refractory metal ions will be tested to determine if further mixing or aging time is required. The intimately mixed powder, paste, liquid, etc. of the electrolyte and refractory metal is then applied to the base metal by spraying, dipping, brushing, stirring, scattering or any suitable distribution means or coating of the mixed refractory metal and electrolyte. , providing a thin coating to the base metal.

A prepared mixture of a refractory metal having the surface of the generator and an electrolyte having the required moisture content and refractory metal ion concentration is prepared to carry out the next step of the invention, namely the deposition of the refractory metal. Stir with the part to be processed in a ball mill without balls to obtain sufficient coverage of both the electrolyte and the part to be processed.

In a wet mixture, the electrolyte is present between the surface of the base metal and the refractory metal and acts in the same way as if particles of properly refractory metal were coated with the electrolyte. The temperature at which the refractory metal is substituted or substituted for the base metal may be room temperature or a suitable temperature. Although this temperature is not limiting in the implementation and operation of the present invention, increasing the temperature has the effect of increasing the reaction rate. At room temperature, about 1 to 168 hours, preferably 6 to 72 hours, is sufficient to impregnate or replace the base metal with the refractory metal. Longer times are not critical and adversely affect the method of the invention. It can be carried out even in a shorter time if a sufficient reaction occurs. The temperature range may be between 0 and 200<0>C, preferably between 10 and 100<0>C, especially between 15 and 40<0>C.
The lower limit of this temperature is not critical and can be lower than 0°C, but this will result in longer reaction times. The areal density of the electrolyte and refractory metal mixture as a protective material that can be applied to the base metal is not limited, and is approximately 0.5 per protective coating M7i2.
The refractory metal particles can vary from a completely uniform coverage of the mixture on the surface of the substrate metal to about 106 particles/Mm2 for 1.0 micrometer particle size.

Particles of size 1-5 micrometers have a concentration of these particles in the range of about 4 x 10 (10 cages/Mm2) for full coverage. Approximately -325 mesh size (4
For particles with a nominal maximum diameter of 4 micrometers, the particle concentration deposited on the substrate metal is approximately 10-104 particles/Mj
It can change to The amount and size of the refractory metal particles applied determines the closeness of the particles and the size of the individual particles after they are actually deposited on the substrate. The drawings attached to the product of this invention are:
1 is a composite illustration of the various possible textures that can be seen on the base metal 10 and within the surface area defined by plane A-A; FIG.

The characteristics of the discrete particles 14 of refractory metal deposited within the surface area of the base metal are to the extent of the implementation of the invention.

For example, the refractory metal present in the surface area of the substrate is substantially the same shape, nominally the same, or slightly smaller in size compared to the powder or granular particles as the refractory metal originally used in the process of the invention. They are metal particles. The features of the invention were demonstrated by microscopic observation of both the refractory metal powder or particles used in the process of the invention and the refractory metal particles deposited on the treated metal substrate. A large number of such deposited particles are no larger than about 2 micrometers in size, with all such deposited refractory metal grains having a size of 0.01 to
It was found to be within the size range of 100 micrometers. Furthermore, a large amount of refractory metal particles 14 having a size both larger and smaller than the average particle size of the refractory metal powder or grains initially used in the process of the invention is added to the base metal 1.
can be deposited on the surface area 12 of 0.

Thus, for example, if the initial shape of the refractory metal particles used in the method of the present invention is a self-crystalline shape with an average size of 1 micrometer or is irregular, the deposited refractory metal particles will have this characteristic. , further exhibiting both large spherical grain shapes up to 10 micrometers in diameter and small adjacent grains with an average size of less than 0.2 micrometers. Even with this additional shape, the deposited refractory metal particles 14 range in size from 0.01 to 100 micrometers, and the number of deposited refractory metal particles is about 2 micrometers. It was found to have a size smaller than a micrometer. The arrangement of individually deposited refractory metal particles may be caused by pre-existing physical or chemical effects such as microscopic pores or valleys and/or machined grooves 16 in the surface area of the base metal. Irregularities are observed on the surface area of the base metal formed by the process, preferentially at the grain boundaries.

The distribution of refractory metal particles on an essentially planar microscopic single phase area of the base metal is clearly spatially disordered. Similarly, microelectrolysis phenomena are thought to produce an inherently spatially disordered shape on a flat portion of the base metal, with initial discontinuities of deposited individual refractory metal particles. Form a mold. Developing the operation of the present invention, these large numbers of individual refractory metal particles are deposited in contiguous molds, and these particles are randomly arranged on an essentially flat area 20 of the base metal. Clusters 18 are formed.

These clusters of particles are spaced apart and preferentially form irregularly in the surface areas of the base metal, such as machined grooves 16. When the reaction of the method of the invention is advanced to another step such as increasing the treatment time or increasing the treatment temperature,
The preferentially and randomly arranged dense area 18 of the individual particles 14 will be adjacent to another central dense area,
Fine-grained (small scale) areas 22 of refractory metal are thus formed deposited within the surface area of the base metal.

These fine-grained areas of deposited refractory metal appear to be continuous as the base metal is indistinct within this area. These fine-grained areas 22 of refractory metal are randomly spaced from each other, but are preferentially irregularly formed in surface areas of the base metal such as machined grooves 16 and similar structures. If the reaction of the process of the invention is made more advanced, and in particular the number of reaction zones is increased by increasing the density of the individual particles on the substrate in that zone, the bonding process of the refractory metals to each other is improved. It becomes even more obvious.

Preferential and randomly arranged fine-grained refractory metal zones 22
will be adjacent to other central fine-grained areas of refractory metal such as 24, resulting in a fine-grained (large scale) area 26 of refractory metal deposited within the surface area of the base metal. Such fine-grained areas 26 of precipitated refractory metal are
Within such areas, the base metal is coated and is therefore visible to the naked eye. These fine-grained areas of deposited refractory metal are separated from each other and are clearly randomly distributed in the surface area of the base metal. The entire base metal 10 is then coated with deposited refractory metal as shown at 28 by continuous lateral growth of the refractory metal in the manner described above.

Furthermore, the refractory metal is built upon itself in a standard orientation on the surface of the base body, so that the refractory metal layer is thickened at 30 and is clearly continuous with the bond of the refractory metal 10 to the base metal 10 . I will provide a. Such distribution and subsequent bonding of the individually separated refractory metal particles deposited as described above provides a deposition pattern unlike other metal deposition methods, including in particular electrochemical methods.

For example, when treated with the method of the present invention, a mild steel sheet material with a diameter of about 3 times its diameter can be produced without appreciable cracks or fractures.
It is apparent to the naked eye that it has a continuous coating that can withstand bending of 8 inch radius and 140 degrees. This apparently continuous coating actually has a discontinuous texture. Thus, treatment of tool steel substrates according to the method of the present invention provides the deposition of discrete refractory metal particles in the form of randomly spaced, densely packed particles. These grain densities preferentially precipitate within the surface area of the base metal and on the exposed substantially planar metal matrix between the carbide grains of the steel. The treatment of SAE Type 1018 steel by the method of the present invention is similar but with a complex pattern of refractory metal particle deposits within the surface area of the substrate. In this example, the refractory metal particles are individually separated and precipitated in the form of randomly spaced dense particles on the substantially flat ferrite microcomponent of the base metal, and are further deposited on the carbide of the pearlite microcomponent of the base metal. Preferentially distributed on ferritic parts. In both types of steel, a continuous metal matrix phase is found in the preferred locations of the refractory metal particle deposits, and in both cases randomly spaced clumps of individually separated particles are present in the substrate. It appears that the metal was deposited on a substantially flat portion of the continuous metal matrix phase. The finished thickness of the precipitated particles forming a bonded coating that can be applied is:
Varies with time, temperature and ion concentration. The electrical current applied when the electrolyte or refractory metal contacts the substrate material also affects coating properties. A starting thickness of a selectively continuous or discontinuous molecular film of up to 0.5 mm thickness is deposited in the surface area of the substrate material.

One feature of the present invention is the use of a portion of the substrate material as a partial replacement or replacement, with no change in the size of the substrate metal detectable by common factory measurement techniques. Only in the most advanced stages of precipitation can a detectable change in magnitude be noted. Finally, according to a special implementation of the invention, very small amounts of at least one corrosion product 2
4 can be shown in the surface area of the base metal.

These corrosion products are essentially solid, electrolyte-insoluble chemical compounds formed as a result of some type of corrosion reaction in which the base metal is chemically attacked by the electrolyte; many of these compounds are It is essentially composed of cations from the base metal and anions from the electrolyte. Therefore, this corrosion product consists of hydroxides, chlorides, nitrates, sulfates, and
Obviously in the form of cyanates, carbonates, acetates and the like, or as a variant more complex base metal compounds such as oxyhydrogen salts, oxychlorides, thiocyanates and the like. This corrosion product tends to nucleate and grow in the surface areas 12 of the substrate 10 and is more accessible to the electrolyte in these areas, especially in other areas where the refractory metal is in direct physical contact with the substrate. There is.

The substantial lateral growth of the corrosion products at least partially surrounds the precipitated refractory metal of the grains 14 in microscopic areas 22 similar to microscopic areas 26, such as 36;
They tend to be buried as in 8, partially buried as in 39, or trapped as in 40. It is believed that these corrosive products adhere to the substrate metal and enhance the adhesion of the refractory metal particles to the substrate, particularly by surrounding or entrapping the refractory metal particles. The composite/coated structure thus created consists of refractory metal particles firmly bonded to the base metal, refractory metal particles surrounded or captured by corrosion products, or fixed by the base, and Composed entirely of encapsulated refractory metal grains. Such a composite structure shows that certain refractory metal particles, especially particles totally engulfed by corrosion products, are present in the surface area as a natural result of the pressing forces generated when the coated part is used. It is anticipated that it will be mechanically embedded or friction welded into the base metal. In this idea, the composite coating acts as a reservoir and ensures a continuous supply of refractory metal particles that adhere to the surface area of the base metal. Furthermore, in some cases the corrosion products themselves act as lubricants, reducing friction and/or wear by their own nature or as porous reservoirs for common lubricants such as oil, graphite, molybdenum sulfide and the like. Decrease. A preferred final step in the treatment of the base metal according to the invention is a rapid hot water wash followed by rapid air drying.
This operation is completed with microelectrolysis, which removes almost all ionization products and salts from around the base metal. The effluent cleaning liquid, usually water, contains unprecipitated useful refractory metal particles suitable for recovery and use in subsequent applications of the invention. Although up to 99% of the total weight of refractory metal particles can be recovered by standard procedures of decanting, sedimentation, centrifugation and similar methods using runoff wash water, all refractory metal particles are cannot be recovered by any method. There are special refractory metal-electrolyte combinations that disadvantageously bond together following this cleaning cycle. This combined process is undesirable as the product is essentially unusable for recycling purposes and cannot be easily regenerated into particles. In such cases, the acid concentration in the wash water should be adjusted to between 1 and 10 volumes of the total wash water to forestall this binding process. It is approved for use at mineral acid concentrations maintained at For example, in a treatment mixture consisting of tungsten metal powder as the refractory metal and calcium chloride as the electrolyte, binding may be prevented by adding hydrochloric acid at a level of about 5% by volume of the total effluent wash water, and then recycling the effluent. It has been found that tungsten powder not consumed in the processing reaction can be recovered by washing and decanting or centrifugation. The concentration of hydrochloric acid used to obtain a suitable wash water concentration is not critical. The invention will be further illustrated by the following examples.

Example 1 In order to apply tungsten metal as a wear-resistant and refractory material to the surface area of a high carbon steel loom traveler, pure tungsten powder is used, although the purity is not particularly critical.

This powder exhibits a -325 mesh, with tungsten metal grains up to 45 micrometers, with most particles even smaller than this size, with a maximum size of just under 1 micrometer. The dried tungsten powder is mixed with dry anhydrous potassium chloride powder of commercial particle size in a ratio of 1 part CaCl2 to 10 parts tungsten powder by weight. These two powders are then mixed or simultaneously ground in a porcelain jar in a jar-type ball mill using 1/4 to 1/2 inch porcelain balls for about 24 hours, and using a mortar and pestle for the same amount of time is also sufficient. . During this simultaneous attrition, the generator surface is provided with refractory tungsten particles and C
The particle size of acl2 is reduced: Cacl2 is deposited or coated on the surface of the tungsten metal powder particles. This co-milled mixture of dry powders was then contacted with humidified air at 60% relative humidity for about 20 hours, and since Cacl2 is hygroscopic, it was added to the above mixture in an amount equal to about 10-20% of the total weight of the wet mixture. Water is adsorbed.

At this point, most of the CaCl2 dissociates into ions and a small amount of tungsten metal powder is also introduced into the solution in ionic form resulting in an equivalent concentration of about 3ρ00-10,000η of refractory metal per liter of liquid phase of the mixture. Ru. This wet, aged mixture is then applied as a slurry by simultaneous stirring of the mixture and the traveler. In addition, the parts are previously cleaned in a CCl4 bath to remove grease, oil or other substances so that the surface area of the steel substrate is exposed to the action and contact of the mixture of electrolyte and refractory metal. . Over a period of 24 hours at room temperature, the electrolyte and the steel substrate jointly act on the refractory metal powder particles and the metal ions to form deposits of metallic tungsten on the surface area of the steel substrate of the traveler. The final step in treating the steel traveler is rapid washing with hot water (80°C to 10°C) followed by rapid air drying. This operation terminates the microelectrolytic action and removes ionization products and salts from around the steel substrate. This product consists of tungsten deposited in the surface area in clusters of randomly spaced individual particles.

This spatially discrete deposit of tungsten particles is infiltrated with solid corrosion products, essentially consisting of hydrated ferric oxide adjacent to the surface area of the steel substrate and deposited as a fixed material. This is considered to be the case. This corrosion product surrounds, traps and partially overlaps the precipitated tungsten particles, forming a composite corrosion product layer fixed on the steel substrate.
The coated steel surface is macroscopically uniform and dark in color;
Microscopically, it is apparent that it exhibits a gray color and preferentially absorbs visible electromagnetic radiation in the wavelength range of 580 to 610 nanometers compared to uncoated substrates.

Treated surfaces of this nature enhance both the adsorption and emission of electromagnetic radiation, the latter being of particular importance with respect to the dissipation of radiant heat. Example 2 Heat Treatment Low Alloy Investigation In order to apply tungsten as a wear-resistant and refractory metal to the surface of a bell gear, a wet, aged mixture of tungsten and CaCl2 is prepared in exactly the same manner as shown in Example 1.

This mixture is then applied as a slurry by coating onto the worn surface of the gear in such a manner as to provide an areal density of about 10 3 refractory metal particles per 2 parts on the surface of the cleaned steel gear.
Over a period of 24 hours at room temperature, the electrolyte and low alloy steel substrate interact with the refractory metal ions to form deposits of metallic tungsten particles on the surface areas of the steel gear. The part is then cleaned and dried as in Example 1. Similarly treated SA
Laboratory sliding wear test of E type 1018 low carbon steel plate was as follows:
At a load of 0.5 kg and a speed of 120 CTII/sec, the abrasion resistance of this treated material was approximately 250 times greater than that of a similar untreated material, as measured by weight loss.

The treated material used in this one hour rapid wear test has the same microscopic appearance as the treated low alloy bevel gear described above. Example 3 Tungsten powder of -325 mesh size is used to apply tungsten as an abrasion-resistant and fire-resistant material to the surface of a component.

The dry tungsten powder is mixed with dry anhydrous CaCl2 of commercially available particle size, and the powder is mixed and co-milled as described in Example 1. This co-abrasive mixture of dry powders is then distributed by sprinkling onto the cleaned wear bearing surfaces in such a way that the surface density of the part is approximately 3.times.10@3 refractory metal particles per m'.

The abrasive bearing surface is then exposed to air at 40-50% relative humidity at 40 DEG C. for 20 hours. During these 20 hours, the electrolyte and the refractory metal ions adjacent to the worn gear surface are
Precipitates of metallic tungsten particles are formed in the surface areas of these surfaces. Example 4 In order to apply tungsten as a wear-resistant and refractory metal to the surface of a part, a wet, aged mixture of tungsten and CaCl2 is prepared exactly as shown in Example 1 above.

A relatively large amount of this mixture is then placed in a stainless steel container which serves as the anode of the electrolytic cell. The wet mixture in this case serves as the "electrolyte" of the electrolytic cell. The resulting polarity was such that a direct current potential of about 1 volt was applied through the electrolytic cell (rustless steel - the substrate to be coated with "electrolyte").
Current was applied for approximately 6 hours, after which the substrate was observed to assume a typical blue color similar to the surfaces produced by Examples 1-3 without the application of current. It is believed that the application of current in this case promotes the precipitation of individual particles. EXAMPLE 5 Loopers and needles of various types and shapes of hardened carbon steel and certain Tarom steels and bundled knives of tungsten steel were prepared in a solution of 1/2 d hydrochloric acid mixed with -325 mesh of powdered tungsten 209. Expose to mixture.

This hydrochloric acid forms an electrolyte and is a mixture of one part acid and five parts water.

The mixture of hydrochloric acid and tungsten before contacting the part to be treated is warmed for 24 hours to form a homogeneous mixture and finally in the form of a wet powder. The water content is adjusted to 9% by weight of the total mixture. Further aging for 24 hours brings the tungsten ion concentration to at least 5,000 per liter of solution.
Let's call it Tnf7. The mixed product is then uniformly spread over the surfaces of the looper, needle and knife at 25° C. at 200 particles per 7 nm@2 and left in an open pan for 12 hours. At the end of this time, all coupons were noted to be slightly darkened. At the end of the reaction period, the coupons were found to have longer wear resistance than similar untreated coupons.

[Brief explanation of the drawing]

The accompanying drawings are schematic representations of the various textural characteristics of the surface areas of the base metal of the present invention, in which 10 is the base metal, 12 is the surface area, 14 is the discrete deposited particles of the refractory metal, and 16 is the machined groove. , 18 is a particle dense part, 20 is a flat part of the base metal, 2
2 and 26 are fine-grained areas, 28 is coated refractory metal, 30
32 represents a refractory metal layer, 32 represents a continuous layer, and 34 represents a corrosion product.

Claims (1)

Claims: 1. A base metal of relatively low wear resistance, a surface area of said base metal, and a fire-resistant material having a melting point of at least 1490° C. deposited within said surface area and adhering to said base metal. The refractory metal is deposited as individually separated particles, a large number of deposited particles are adjacent to each other in a densely packed form, and the densely packed particles of the refractory metal are spaced apart from each other, and the refractory metal is deposited as individually separated particles. A relatively low abrasion resistant base metal article coated with a refractory metal, characterized in that it forms an adherent abrasion resistant coating on the metal. 2. The refractory metal is a large number of particles in its own crystalline form with a size of less than 2 micrometers, a large number of equiaxed particles with a size of less than 10 micrometers or in its own crystalline form or acicular particles. A low wear resistant base metal article coated with a refractory metal according to claim 1. 3. Solid corrosion products of the base metal formed in the surface area and fixed to the base metal, said corrosion products at least partially surrounding other refractory particles at that location, said other refractory particles A low wear base metal article coated with a refractory metal according to claim 1, wherein said other refractory particles provide additional wear resistance without adhering to the base metal. 4. The refractory metal-coated low-temperature refractory metal-coated refractory metal according to claim 1, in which a large number of dense parts are adjacent to each other to form a large number of microscopic refractory metal areas, and at least some of the areas are separated from each other. Abrasion resistant base metal article. 5 An electrolyte material that can dissociate into ions and has a conductivity ratio of 0.13 to 0.93 calculated with a 0.1 standard solution is prepared and deposited on the surface area of a relatively low wear-resistant substrate material. A particulate refractory metal to be deposited is prepared, the refractory metal has a melting point of at least 1490°C, at least a portion of each refractory metal particle to be deposited is a surface of the generator, and the refractory metal particle is at least Sufficient time to surround with electrolyte,
99-50% by weight of a refractory metal and 1-50% by weight of an electrolyte, the moisture content of the mixture being sufficient to maintain the admixture at an electrolyte resistance of less than about 10^6 ohm-cm. at a concentration of refractory metal ions of 1 to 60 ml per liter of solution, in contact with and at least partially covering the surface of said substrate material with a mixture of particulate refractory metal and electrolyte, and at a temperature of 0°C to 200°C. reacting the admixture with the substrate material at a temperature of A method of depositing a refractory metal onto a relatively low wear-resistant substrate metal. 6. A method for depositing a refractory metal on a relatively low wear-resistant substrate metal according to claim 5, wherein the refractory metal is deposited in the form of individual particles. 7. A method for depositing a refractory metal according to claim 5 on a relatively low wear resistant substrate metal, wherein the reaction is carried out at a temperature of 15° to 40°C. 8. Depositing a refractory metal according to claim 5 on a relatively low wear-resistant substrate metal, depositing a refractory metal with a thickness of up to 0.5 mm in the surface area of the substrate metal. Method. 9. A method for depositing a refractory metal according to claim 5 on a relatively low wear resistant substrate metal, wherein the electrolyte has a dissociation ratio of 0.60 to 0.93. 10. The refractory metal according to claim 5, wherein the electrolyte is one of mineral acids, organic acids, bases, salts of the acids and bases, and acid anhydrides, on a relatively low wear-resistant base metal. How to deposit.