JPS58501382A - High hardness material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] High hardness material The present invention provides improved tungsten-carbon materials and methods for making such materials. Regarding how to

Tungsten carbide has been used as a wear-resistant material for many years. Ru. Such carbides are -1, tungsten carbide, a ductile metal, For example, it can be sintered with cobalt to produce a material with acceptable hardness, strength and toughness. Manufactured by

Further, such carbides are described, for example, in U.S. Patent No. 3. g74,672 ( Tarver) produced by chemical vapor deposition method, However, they were not completely satisfactory. tungsten carbide In precipitation, two forms of carbide 9, WC or W2C, are the most common. Manufactured. Of these forms, the WC is more flexible (and more coercive) than the W2C. Therefore, it is considered more desirable. Analytes produced by the Tarver method After studying the artifact, I found that it was a form of W2C. Such precipitates , relatively brittle (and lacking in strength), making it unsuitable for many purposes.

Other chemical vapor deposition methods for depositing carbides are described in U.S. Pat. No. 3,814.625 ( Lawin and E (ayman). This Lewin and In the methods of Hayman and Hayman, the tungsten carbide precipitate is Reacting the fluoride of ten with hydrocarbons and hydrogen at a temperature of 400-1000C It is manufactured by L+ewin and Hayman are W.C. It is intended to form W2C or mixtures thereof. However, N, J, A Subsequent research by Rcher revealed that only the less desirable W2C It was shown that it could be produced by the method of In and Hayman. “Tungst en Carbide Coatings on 5teel-N, J, Ar cher (Conference on Chemical Vapor) Deposition+ 5th International Conference ence 1975 * The Electro Chemical 5oc iety+Pr1nston, N6w Jersey) o Also, Archer According to the study of Lewin and Hayman, precipitates are composed of long crystals and Consisting of a crystal habit of columnar crystals, these may be further responsible for the low tensile strength Ru.

The sixth form of tungsten carbide, namely W3C, is described in British Patent Specification No. , No. 540.71'8 (published February 14, 1979) and Wear, Vol. 48, 237-250 (1978), N. J. Archer et a. It was described in the author. This material was initially characterized by the Xa diffraction spectrum. , called beta tungsten or A15 tungsten structure (Herman, et al, 5tructorbericht, Vol. 1,928) was taught by these early researchers to be W2O. Archer etc. The precipitates of al are tungsten hexafluoride and benzene, toluene or oxygen. Formed by chemical vapor deposition using urethane. These precipitates are not suitable for some applications. However, the particles were relatively thick (and elongated, and included a columnar arrangement. Therefore, the analysis The precipitate has a relatively low tensile strength and the precipitate is larger than 50 micrometers. showed lateral cracking.

U.S. Patent No. 4,162,345 (Robert A, Holz1. Invention of the present application) (Published July 24, 1979) has an unusually high hardness and tensile strength. tungsten and carbon or molybdenum and carbon, resulting in tough precipitates. The production of precipitates is described. Such precipitates do not contain columnar crystals; Instead, it is characterized by a structure consisting essentially of fine, equiaxed connections. this The hardness, strength and flexibility of the precipitates are similar to those of tungsten carbide as previously mentioned. is greatly improved over prior art deposits.

In the method described in the F(olzl patent), a gaseous volatile... , a gaseous organic compound containing carbon, hydrogen, and oxygen and separated from the surface of the support. At that point, a substitution reaction is performed to produce an intermediate product.

Thereafter, at least a portion of the intermediate product is exposed to hydrogen gas and the heated surface of the support. React at

The method described in the Ho1zl patent produces a precipitate with excellent mechanical properties. It has proven to be very effective in manufacturing. However, precipitates and supports If the expansion coefficients between the bodies differ substantially, such precipitates should be kept as low as possible. It would be desirable to be able to manufacture at high temperatures.

As the support containing the precipitate cools to ambient temperature, the support and precipitate Both contract. Thermal expansion of precipitate 4 If the rate is substantially different from that of the support, the support and precipitate will collect at different rates. Shrink. When cooling from a relatively high temperature, this is the boundary between the precipitate and the support. can create stress conditions, which can affect the adhesion of the deposit to the support. may be received. This separates the precipitate from the support and makes it independent on its own. This is not a problem, and may in fact be advantageous when constituting a product that is

However, if it is desired that the precipitate and support be of monolithic structure, poor contact may occur. wear can be a significant problem.

Other problems associated with high temperatures are metal supports such as steel and bonded tungsten. Occurs in association with ten carbide. At temperatures above about 5,500 ℃, the steel support deforms due to stress relief or weakens due to annealing or metallurgical transformation. It may happen. Also, the bonded tungsten carbide has a Mechanical properties may deteriorate at elevated temperatures. Weakening of the underlying support is a question when the final product is an independent object in itself that is removed from the support. Although not a problem, if the final product is a support coated with a hard metal precipitate, That would be a problem.

Therefore, one object of the present invention is to produce a material at a relatively low temperature to eliminate precipitates and supports. A tungsten and carbon alloy that reduces problems associated with differential thermal expansion with the carrier. The objective is to provide a hard and strong precipitate.

An additional object of the present invention is to provide an improved analysis of tungsten and carbon-50 alloys. The product is manufactured on a support of steel or other base metal, and mechanical deformation of the support, metal This is to avoid problems associated with chemical transitions or stress relief.

Another object of the invention is to provide an improved precipitate of tungsten and carbon alloys. This is fabricated at relatively low temperatures on a bonded tungsten carbide support. The aim is to prevent possible deterioration of the mechanical properties of the support such as.

Yet another object of the invention is to improve the mechanical properties of tungsten and carbon. The goal is to produce alloy precipitates with high quality.

Other objects and advantages of the invention will become apparent from the description below.

Very generally, the thermochemically precipitated products of the present invention include tungsten and charcoal. consists essentially of a two-phase mixture of carbon and oxygen, with the -phase being pure tungsten. Ten, and the other phase is A15 structure. Precipitates do not contain columnar distribution of particles , and the hardness is greater than 1200VHN. The average particle size is 0.1 micron. It's small.

The present invention builds on the broad teachings of the aforementioned U.S. Pat. No. 4,162,345 (Holzl). Within the range, high quality, but under X@ diffraction analysis, as described in the said patent. It is acknowledged that it is possible to obtain a precipitate different from that shown in the figure. tungsten and main contains finely dispersed tungsten carbide 9 in the form of WC. The model described in the above-mentioned Ho1zl patent 1. The precipitates of the present invention are mainly composed of tungsten and A. This is the form of a mixture with the 15 structure.This 5 conclusion is based on the Norelco (Ph1lips-Norelco), Diffractometer, Linickel Island X-ray diffraction analysis using 6uK radiation at -55kV and 1.5iA Based on analysis (.

Diffractometer scans were obtained in 20 ranges from 30° to 105°. Average grain size of precipitates The degree is smaller than 0.1 micron, and the particles are not in a columnar arrangement, but in Archer + Substantially elongated (i.e. 5-10 times the width) reported by 5upra This material has a Vickers hardness greater than 1200 kp/m2. shows.

The so-called A15 structure is a particular type of crystal structure that occurs in poly() materials.

For example, the A15 structure of chromium oxide is M-V-Nevitt+ Trans actions of the Metallurgical 5ociety As reported in 652-355 of AIME* June 1958. There is. Tungsten-based A15 structures are sometimes referred to as beta-tungsten. and has been characterized by various authors as W3C or W2O.

X-ray diffraction analysis shows that the structure of the material of the invention is a pure tungsten phase and an A15 structure. ・A15 phase is a mixture of tungsten carbide or tungsten carbide. It is a mixture of gsten carbide and tungsten oxide. however, Certain properties of this material are such that the A15 structure itself is in the W3C or draw the conclusion that carbon or oxygen is lower than the stoichiometric value of W2O. there was. This structure does not form from the melt (but only from deposition under certain conditions). is a metastable compound, and when heat treated at about 600-700C, the A15 structure The structure decomposes, or whether carbon or oxygen is present, subsequent X-ray Transitions so that the diffraction does not show them. However, gravimetric analysis indicates that oxygen is still present. Moreover, the hardness decreases somewhat with heat treatment. , it is still high (usually reduced by a proportion less than about 20%) of carbon or oxygen. The phase can be seen to be particles when magnified 106 times after heat treatment. The nature of this phase Although it is currently unknown, it is probably due to the dispersion of atoms. However, carbon or Oxygen may also exist as amorphous carbides or oxides at grain boundaries. be.

In either case, the percentage of carbon or oxygen in the precipitate of the invention is Substantially less than is present in W3C or W2O. For example, W31IC The weight percentage of carbon is about 2.1%. On the other hand, present in the folded material of the present invention The carbon content appears to be less than about 1%, and may be as low as 0.1%.

Moreover, the amount of carbon is directly proportional to the amount or hardness of A15 structures present in the precipitate. I don't think so. Additionally, heat treatment generates substantial heat, resulting in the A15 structure Phase decomposition or transition is indicated.

This fever is approximately 14 kilocalories 71, and 8 It does not appear to be directly related to the actual carbon or oxygen content by weight of the material.

The precipitation conditions described below were adjusted to avoid the volume fraction of the A15 structure being too low. Select. If the volume fraction of A15 structure is too low, the hardness value of the precipitate is not useful. It decreases as much as possible. The lowest useful hardness value is typically around 1200 bits. and requires a volume fraction of A15 structures greater than about 20%.

The high hardness values of the inventive precipitates are due to the so-called mixture approach for two-phase materials. Not expected from theoretical calculations based on the law. Archer et aL 1' 978 + 5upra is 2000-2500v for both W2C and W3C It is reported to have a hardness in the range of HN. Tan using this mixture method Equal volume mixing with Gustair (460VHN) and W3C (2500WE (N)) If we calculate the hardness of an object, we will arrive at a hardness number of 1500. however , the hardness of the material of the invention is as follows: an equal volume mixture of pure tungsten and A15 structure Typically 2000 VE (more than N, and approaching 2500 VE (H) Ku.

This unexpected hardness in the precipitates of the present invention is due to the purification of the particles in the A15 phase. and X-ray diffraction analysis of the precipitate of the present invention believed to be the result of internal compressive stress. According to the analysis, the lattice dimensions of the precipitated A15 phase can be calculated. Analysis of the present invention A15 phase in the product, cubic structure, 5.015 to 5.039 ang Trom's case 9 special table 1986-501382 (4) It is determined to have a child spacing. This is British Patent No. 1.540.718 ( Archer and Hayman) K stress-free W3C 5, [34B different from the reported grid spacing. This difference in the lattice space of the A15 phase of the precipitates of the present invention is , indicating internal compressive stresses in the A15 phase up to several thousand megapascals (MPa). child Internal compressive stresses such as Because the material behaves much harder than what could normally be expected, desirable.

When obtaining such a precipitate, a gas flow of tungsten fluoride is combined with carbon, together with a gaseous flow of one or more organic compounds containing oxygen and hydrogen , established within a chemical vapor deposition reactor. Gaseous organic compounds are small at 20C. (both selected to have a vapor pressure of 1 Torr and contain less than 4 carbon atoms) do. A flow of hydrogen gas is also established within the reactor. the flow of gas introduced into the reactor; The hotbed of the support, and the temperature of the gas, compressive stress, hardness, and microscopic properties are as described above. Two phases consisting of a pure tungsten phase and an A15 structured phase, such as a coating is selected to be produced on the support.

The A15 phase can theoretically consist of only tungsten and oxygen, but Attempts to achieve 15 structures using only oxygen in the body stream thus far Due to unsuccessful attempts, some carbon in the precipitate was found to be unnecessary.

0 In the method of the present invention, although similar to conventional chemical vapor deposition, it is not truly one. Elephant order happens. The method of the invention uses a reaction system that is essentially similar to a chemical vapor deposition reactor. Use a vessel. However, this equipment does not allow typical chemical vapor deposition methods to occur. operate in a certain way. Typical chemical vapor deposition deposits a solid phase directly onto the surface of a support. It involves a single reaction with a gas at the surface of a strut in a reactor to form. typical chemical vapor deposition has relatively large particles arranged in a columnar crystal habit. , depositing a coating.

Thus, metallurgical examination of a cross-section of a typical chemical vapor deposition deposit reveals columns of particles. are shown, and these particles are larger than a few microns and are attached to the surface of the support. It is arranged with pillars that extend vertically. Such precipitates are typically very Adjacent pillars of grains tend to crack easily, producing long regions of weakness.

In the method of the present invention, in U.S. Pat. No. 4,162,345 (Holzl) Following the more general method described, the initial reaction is displaced from the surface of the support. Wake me up with Buddha.

This reaction is derived from gaseous organic compounds containing hydrogen, carbon and oxygen. Fluoride of tungsten (preferably involves the decomposition or partial reduction of WF6). The subsequent reaction with hydrogen gas produces the final A precipitate is formed.

The method of the invention is characterized by a gaseous reaction that is dependent on the temperature of the support and the temperature of the gaseous reactants. It is possible to use a material with higher hardness and strength by using a flow rate that ungsten A15 structure deposits at a temperature of about 650C or lower. Based on the discovery that it can be manufactured using

Various combinations of these millimeters, some of which are shown in the following examples. As described, the desired precipitate can be produced.

Therefore, the present invention provides improved high quality precipitates at temperatures well below 650C. amazing and unexpected in that it can be obtained at Not possible. Problems arising from differences in thermal expansion coefficients between the deposit and the support, ′ and the support Problems with weakening the body are thereby avoided. Therefore, the present invention provides the desired This is particularly important when the final product is a coated support product. arise Precipitates are very small, non-columnar and non-elongated particles in the Al1 phase. Tungsten and A15 structure characterized by internal compressive stress stress It is a mixture with things. In addition to high hardness, the precipitates are also highly abrasion resistant due to the sand particles. As shown in the figure, it shows an extremely high amount of wear. The hardness of the precipitate is appears to be directly related to the amount of A15 structure or phase present. Typically, The higher the proportion of A15 phase in the precipitate, the higher the hardness, and vice versa. In addition, the smaller the amount of A15 phase in the precipitate, the lower the hardness. Before As mentioned above, the amount of carbon or oxygen in the precipitate depends on the A15 structure in the precipitate of the present invention. 12 things are stoichiometric Since it is not W3C or W2O, it does not appear to be directly related to hardness.

The amount of A15 structure produced generally depends on the reaction rate and the gas introduced into the reactor. related to the preheating temperature. Thus, the higher the preheating temperature, the higher the A15 structure. The amount of is typically large. Similarly, the lower the reaction rate (the more precipitates - The amount of A15 phase present therein will typically be high. These parameters For example, the hardness of 2600 Vickers can be achieved by changing the It can be obtained by setting the percentage of lath oxygen to 0.1 to 1% by weight.

The amount of gaseous organic compound used, i.e. its flow rate, generally depends on the temperature of the support. , will depend on the fluoride flow rate, hydrogen flow rate, and gas temperature. parable For example, oxygen atoms versus tung in fluoride using methanol as the gaseous organic compound. The ratio of the amounts of Sten atoms is preferably about 0.04 or less. In addition, gaseous organic The compound flow rate is related to the amount of hydrogen flow. Generally, using methanol This ratio would be about 0.005. Other gaseous organic compounds present some difficulty. Sometimes it happens. For example, dimethyl ether reacts in the decomposition of WF6. It is less sensitive and would require greater concentrations to achieve the same effect.

Additionally, the amount of gaseous organic compound used depends on the temperature at which the gas is introduced into the reactor. Significantly affected. When preheating a gas, the amount of organic compounds in the gas required is , substantially reduced. The temperature of the gas is controlled by a suitable preheating grate or other heating device. However, the temperature of the gas also depends on the general conditions in and around the reactor. may be affected by the situation. For example, the heat radiated from the support is It will affect body temperature.

The initial reaction that partially decomposes the fluoride in tungsten is due to oxygen or oxygen-containing groups. with one or more fluorine atoms. As mentioned above, gas The ratio of organic compounds to fluoride is low and the exact ratio depends on the specific Depends on temperature, pressure and reaction components. The exact ratio used is the oxygen atoms in the gas stream. is more easily characterized by the ratio of the number of tungsten atoms in the gas flow to the number of be able to. In general, higher ratios are acceptable at higher precipitation v degrees. and lower ratios are acceptable at lower precipitation temperatures.

For example, at 60 DC, the preferred ratio is about 1 to 6, whereas 60 At 0C, the preferred ratio can be as high as about 1:500. Habo An oxygen to metal atom ratio of 1:100 provides sufficient particle size at a precipitation temperature of 450c. Although it can be used to produce purification, 1:40 is preferred at this temperature. acid The maximum element-to-metal ratio is the point at which precipitation is completely inhibited or the precipitate becomes abnormally hard. Determined by the point at which it becomes stiff and brittle.

The hardness of the precipitate depends on the gaseous organic 4 used as a reaction component. It can be influenced by the amount of compound and also by the density of the organic compound. For example, organic When the ratio of reactants to tungsten fluoride is constant, acetone (6 carbons) The hardness obtained for precipitates made from ethanol (having two elementary atoms) is carbon atoms). Next, it is made from ethanol. The precipitate made from methanol (which has one carbon atom) is Hard. A precipitate made from dimethyl ether (with two carbon atoms) Similar to that made from tanol (which also has two carbon atoms).

As these results show, hardness depends on the ratio of the number of carbon atoms to metal atoms in the reactants. Therefore, it will be substantially affected.

When the volume ratio of the reaction components is constant, this variation in hardness is as large as 2:1. Sometimes. For example, about 1000kl? /m1lI2 Vickers hardness is reaction can be obtained using methanol as a component and 2500 to 9/1ia2 Hardnesses in excess of 100% could be obtained using acetone as the reaction component. Yes Mixtures of materials can in fact be used to adjust the hardness to the desired hardness. about Selected hardness ranging from 1000 kg/ml112 to approx. 3.900 kg7mn2 can be achieved through appropriate experimentation using these guidelines. organic compounds are , alcohols, ethers, aldehydes, and ketones. Can be done.

Certain limitations exist in the selection of organic materials.

The organic compound is heated at a temperature substantially below the surface temperature of the support, typically 100 to 2 It must be partially decomposed at temperatures below 00C, thereby It turns out that tungsten must be partially decomposed by fluoride. , is of primary importance. The reaction between fluoride and organic compounds causes the surface temperature of the support to When approached, the addition of organic compounds to this chemical system may lead to abnormal particle purification precipitates. is invalid for generation. Chemical vapor deposition usually occurs.

Additionally, at higher temperatures, if the organic reactants no longer react with the fluoride, If so, it pyrolyzes itself and forms carbon soot. Ethyl alcohol is six This is a good example of a material that is highly reactive with tungsten fluoride and is therefore suitable. Ru.

Another important limitation in the selection of organic compounds is volatility. Use this method normally For implementation, it requires materials with considerable volatility. This is because many organic disqualify the component. The organic compound used has a temperature of at least 1 Torr at 20C. It is generally necessary to have a vapor pressure. Generally contains more than about 6 carbon atoms. Materials that do tend to be not volatile enough. Also, more than about 3 carbon atoms Organic reaction components containing Ru. The present invention is not limited to the organic compounds mentioned above, and routine evaluation has shown that this disclosure It includes other organic compounds that a person skilled in the art who has read the following may find suitable. 4 pieces Preferably fewer carbon atoms are present.

16 Volatile tungsten fluoride is suitable within the ξ parameter of this method. As long as it is sufficiently volatile, it can be used in the present invention. Rokufu Tungsten chloride (WF″6) was found to be most suitable in the method of the invention. .

Inert gas, e.g. nitrogen, to control heat transfer and production rate. , argon or helium are often used as diluent gases in this method. Ru.

Once the initial substitution reaction partially decomposes the tungsten fluoride, it The above reactions occur. This reaction occurs at or near the surface of the support; A desired coating is then deposited.

The hydrogen is used for further reaction with partially decomposed fluoride. initial reaction other decomposition products that may participate. The exact order of the reactions is not understood. but However, hydrogen reacts and removes the remaining fluoride from the decomposition products of the first reaction. When removed, it is inferred. In both cases, extraordinary strength and unity A hard precipitate is obtained.

Hydrogen may be present with or downstream of the initial reaction components (but, of course, upstream of the support). ) can be injected. For hydrogen fluoride, all other parameters are constant. At some point, it will affect the precipitation rate. In general, the higher the hydrogen flow rate I see, the precipitation rate increases. However, high hydrogen flow rates cause discontinuity of precipitates. This may result in connections or holes. This possibility increases the flow rate of gaseous organic compounds. , but this would affect the fragility of the precipitate accordingly. cormorant.

The precipitates of the present invention have an average size of less than about 0.1 micron and an irregular distribution of phases. characterized by a crystalline structure consisting essentially of homogeneous, fine and equiaxed grains, with can be attached.゛The former characteristic is similar to the typical columnar crystal habit of conventional chemical vapor deposition. It's a contrast. Precipitates have unusually high wear resistance and unexpected hardness I understand.

on steel or other active support materials, e.g. cast iron, titanium or aluminum When depositing the coating of the invention on a substrate, the support is first coated with a more noble metal material, Preferably, the gussets are coated with copper by electrochemical deposition. child This film is formed by forming alloy precipitates by the method of the present invention (depending on the amount of gas used). It will protect the support from attack.

Example I 2.5m x 76r+a graphite rod k, internally airtight quartz en is rope (envelope) in a dielectrically heated graphite furnace. graphite tungsten hexafluoride at 200 d/min. 00 d/min hydrogen, 4 d/min methanol, and 5300 d/min N2 gases The mixture was poured onto a rod in the oven. The preheating temperature of the gas was 600C. This system The total pressure inside is maintained at 250 Torr, and the effluent gas is kept at 8 The furnace was evacuated by a vacuum pump. The precipitation was carried out for 1 hour, after which the flow of reactive gas The flow was stopped and the bar was allowed to cool.

A shiny, smooth, cohesive, cohesive coating was observed to be deposited on the bar.

The composition of the coating was determined by X-ray diffraction to be tungsten phase and A15 phase, with a filtration capacity of 3%. Mainly composed of a mixture of tungsten and 67% by volume A15 structure. It was decided that Hardness is 1820V when measured using a load of 500 de The lattice spacing of the A15 structure was approximately 5.OA, and 3. It exhibited an internal hydrostatic compressive stress of 200 Mpa. The graphite support is coated with The prestress shown was chosen to have exactly the same coefficient of expansion. was unique to the coating.

Example■ Pre-plated with 5μ nickel, inner diameter 761nm x length 2000rnm. The invention was carried out on a steel cylinder to coat the inner surface as follows.

WF6200rnl/min 82 1200m 11 minutes 0F (30CH3 (dimethyl ether) 15mA'/min N2 1500$/min Temperature 425C Gas preheating 200C Deposition was carried out for about 2 hours and a coating thickness of 15-18 microns was obtained.

Bicat of 2'200 VHN (ky/mtn 2) using a load of 500y- A shiny, smooth, adhesive, cohesive coating with a hardness of 100% was observed. X-ray circuit Analytical analysis was similar to Example I.

Example■ A wear test was carried out on the precipitate of Example H using a small sandblasting device. provided. 90 psi silica sand was applied to the sample at a 22.5° angle for 20 minutes. Aimed for hours. Weight loss was measured and converted to volume loss, and similarly tested 800 The coating was compared with a hard chromium plated steel sample. The coating of the present invention is 3X10-, ’cIrL3/hr, compared to 6 for chromium-plated steel. It had a wear rate of 13 x 10-'cm3/hr.

Tests on 26% chromium stainless steel were similar to those for the coating of the present invention. The results showed that

Example■ Coatings were produced under conditions similar to those of Example ■, but using the following flow rates: did.

WF6 10100O/min H2500d/min N2 500ml/min Ethanol 5ml 11 minutes Pressure: 200 torr Support temperature 450C Gas preheating 200c 20 The hardness of the precipitate was 2000-2500vHN using a load of 50OFF. .

Example■ Using conditions similar to those of Example ■, but with 2.5 M/min of methanol and 2. ．． Using a dimethyl ether flow rate of 5 m/min, the precipitate was 1500 Vf (It had a hardness of H.

Therefore, it is clear that the method of the present invention is effective at relatively low support temperatures. , can produce deposits with excellent hardness and wear resistance. Valid results are approximately 16 ma This can be achieved by using a support with a coefficient of thermal expansion as high as Ikromedol/C. and thus supports can be made of ferritic and martensitic steels, cast iron, etc. and precipitation hardened steels. The geometry of the support is simple or If the support has substantial compliance due to low yield strength or In special cases, expansion support can be used.

Better throwing power due to the lower deposition rates uniquely achievable in the present invention and more uniform precipitation occurs.

Also, the lower substrate temperature provides flexibility in heating the parts to be coated. analysis Because the particles in the ejected material are extremely small and symmetrical in size, they have a stronger , a more wear-resistant material is obtained. Moreover, the conical particle growth structure is more Although sometimes present in precipitates made at low temperatures, they do not occur in the present invention. this Such structures can introduce weak regions in the precipitate.

Procedural amendment (formality) %formula% 1.Display of the incident PCT/US82101045 High hardness material 3. Person who makes corrections Relationship to the incident: Applicant address Name: Dart Industries Incorporated 4, Agent Address: 2-2-1 Otemachi, Chiyoda-ku, Tokyo Submission of translation of written amendment (Article 184-7, Paragraph 1 of the Patent Act) April 4, 1982 Mr. Kazuo Wakasugi, Commissioner of the Patent Office 1. Display of patent application PCT/USB2101045 2. Name of the invention High hardness material 5 Patent applicant Address: 60062, Illinois, USA. North Spurtsk.

2211 Saunders Road Name: Dart Industries, Inc. Name (2770) Patent attorney Kyozo Yuasa 5. Date of submission of written amendment February 4, 1982 6. List of attached documents (1) One translation of the written amendment The scope of the claims 1. Two-phase mixture of tungsten and carbon or tungsten, carbon and oxygen consisting mainly of particles, without columnar distribution of particles, larger than 1200 VHN thermochemically precipitated with hardness and an average particle size of less than 0.1 micron In the product, one phase consists of pure tungsten and the other phase has A15 structure. , the tungsten phase is present at about 20-90%, and the product is about 0. characterized by having a carbon content greater than 1% by weight and less than about 1% by weight A thermochemically precipitated product.

2. The carbon content of claim 1 is greater than about 0.1% and less than about 1%. Thermochemically precipitated products.

3. When heat treated at about 600C to 700C, the A15 structure transforms and its wherein said hardness is maintained at least half of its pre-heat treatment hardness. 1. The thermochemically precipitated product according to 1.

4. The product of claim 1 comprising about 20 to about 90% pure tungsten. thing.

5. The A15 phase is internally prestressed in compression. Thermochemically precipitated products.

6. The thermochemically analyzed method according to claim 5, wherein the prestress exceeds 1000 MPa. product released.

7. The lattice spacing of the A15 phase was determined by X-ray regeneration analysis, and was smaller than 5.04A. Substantially small Thermodynamically precipitated products.

8. Two-phase mixture of tungsten and carbon or tungsten, carbon and oxygen consisting mainly of particles, including no columnar distribution of particles, with a hardness greater than 1200 VHN and has an average particle size of less than 0.1 micron, the coating having -phase is made of pure tungsten, and the other phase is made of A15 structure, and the tungsten The stainless phase is present at about 20-90% and the coating is greater than about 0.1% by weight and Metal support having a coating characterized by having a carbon content of less than about 1% by weight A coated support product consisting of a body.

9. The support has a coefficient of thermal expansion of less than 16 micrometres/meter/C. The coated support according to claim 8, which is a ferrous object. product.

10. The support is a coated support material consisting of bonded tungsten carbide. A product.

11. a support, a tungsten fluoride gas flow within a chemical vapor deposition reactor; and a gas of one or more organic compounds containing carbon, hydrogen and oxygen. the gaseous organic compound and the gaseous tungsten fluoride; This allows the substances to react away from the surface of the support, in a substitution reaction. Partially decomposes the gaseous tungsten fluoride and the gaseous organic compounds and the gaseous products of the substitution reaction are combined with hydrogen gas on the surface of the support. to produce particulate material that precipitates on the support, and the gas have a vapor pressure of at least 1 Torr at 20C and less than 4 the one or more gaseous organic compounds containing no carbon atoms; In the displacement reaction of tungsten with fluoride, the reaction occurs at a temperature lower than the temperature of the support. tungsten and carbon or tungsten tungsten and carbon and oxygen, the − phase is pure tungsten, and the other A method for depositing a two-phase material of hard fine particles on a support, the phase of which has an A15 structure. the support is maintained at about 300 to about 650C, and the gas flow is The ratio of tungsten atoms to carbon atoms in the gas flow is greater than 6:1, and the gas flow The ratio of tungsten atoms to oxygen atoms in the film is about 3:1 to 500:1. A method characterized by:

12. Claim 1, wherein the tungsten fluoride is tungsten hexafluoride. The method described in 1.

13. The gaseous organic compounds include alcohols, ethers, aldehydes and keto 12. The method of claim 11, wherein the method is selected from the group consisting of:

14. The gaseous organic compound is methanol, ethanol, dimethyl ether, Claim 11 selected from the group consisting of ethylene oxide 9 and acetone. The method described in.

15. The method according to claim 11, wherein the gaseous organic compound is methanol. .

16. The method according to claim 11, wherein the gaseous organic compound is ethanol. Method.

1Z According to claim 11, the gaseous organic compound is dimethyl ether. the method of.

18. The method of claim 11, wherein the gaseous organic compound is acetone.

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Claims (1)

[Claims] 1. Tungsten and 'carbon' or two tungsten, carbon and oxygen Mainly composed of a phase mixture 1, -: the phase is pure tungsten, and the other The phase is A15, structure is 2A"v2, does not contain columnar distribution of particles, and is 1200 VHN. Thermal Chemically precipitated products. 2. The carbon content of claim 1 is greater than about 0.1% and less than about 1%. Thermochemically precipitated products. 3. When heat treated at about 600t:' to 700t:', the A15 structure transforms. and said hardness is maintained at least half of its pre-heat treatment hardness. A thermochemically precipitated product according to claim 1. 4. The product of claim 1 comprising about 20 to about 90% pure tungsten. thing. 5. The A15 phase is internally prestressed in compression. Claim 1 Thermochemically precipitated products. 6. The prestress is greater than 100 MPa. Precipitated product. 7. The lattice spacing of the A15 phase is determined by X-ray countermeasure analysis and is less than 5.04A. A thermodynamically precipitated product according to claim 1, which is substantially small. 8. Two-phase mixture of tungsten and carbon or tungsten, carbon and oxygen The - phase does not contain a columnar distribution of pure particles, and the 1200' VHN have a hardness greater than 0.1 microns and an average particle size smaller than 0.1 micron A coated support product consisting of a metal support having a coating thereon. 9 The support has a coefficient of thermal expansion of 13 micrometers/meter, less than /C. The coated support according to claim 8, which is a ferrous object having retention product. 10. The support is a coated support material consisting of bonded tungsten carbide. A product. 11. In a chemical vapor deposition reactor, about 600 to about! 5C1 temperature support, tungs Flow of fluoride gas and carbon, hydrogen and oxygen containing one or more : provides a gaseous flow of an organic compound above which the compound is heated at 20C. (both have a vapor pressure of 1 torr and contain less than 4 carbon atoms, The one or more gaseous organic compounds are the gaseous organic compounds $JL! ,Before 1. In the substitution reaction of gaseous tungsten with fluoride, the temperature is lower than that of the support at t. 1. The above-mentioned gaseous organic compound and the above-mentioned gaseous tan This causes the fluoride of gsten to react away from the surface of the support. 1. In the substitution reaction, the gaseous tungsten fluoride and the gaseous The organic compound is partially decomposed and the gaseous products of the displacement reaction are deposited on the support surface. and react with hydrogen gas at the temperature of the support to deposit 23% on the support. Consisting of gesten and carbon or tungsten, carbon and oxygen, - phase is pure Two phases of hard fine particles, one of which is tungsten and the other phase is an A15 structure. A method of depositing material onto a support. 12. Claim 1, wherein the tungsten fluoride is tungsten hexafluoride. The method described in 1. 16, 'The gaseous organic compounds include alcohols, ethers, aldehydes 1 and selected from the group consisting of ketones. The method according to claim 11. 14. The gaseous organic compound is methanol, ethanol,) methyl ether, ethylene oxide, and ace15, the gaseous organic compound being methanol , the method according to claim 11. 16. The method of claim 11, wherein the gaseous organic compound is ethanol. . 1Z According to claim 11, the gaseous organic compound is dimethyl ether. the method of. 18. The method of claim 11, wherein the gaseous organic compound is acetone.