CA1047899A - Process for coating inorganic substrates with carbides, nitrides and/or carbonitrides - Google Patents
Process for coating inorganic substrates with carbides, nitrides and/or carbonitridesInfo
- Publication number
- CA1047899A CA1047899A CA219,428A CA219428A CA1047899A CA 1047899 A CA1047899 A CA 1047899A CA 219428 A CA219428 A CA 219428A CA 1047899 A CA1047899 A CA 1047899A
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/22—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the deposition of inorganic material, other than metallic material
- C23C16/30—Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
- C23C16/34—Nitrides
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/22—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the deposition of inorganic material, other than metallic material
- C23C16/30—Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
- C23C16/32—Carbides
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/22—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the deposition of inorganic material, other than metallic material
- C23C16/30—Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
- C23C16/36—Carbonitrides
Abstract
Abstract of the Disclosure A process for coating inorganic substrates, especially metallic or metalloid substrates; sintered metal carbides and carbon materials with carbides, nitrides and/or carbonitrides; using certain nitriles as sources of carbon and nitrogen, is described. High deposition rates and smooth coatings of good to very good adhesion are achievable by this process.
Description
~478q,~
The present invention relates to a process ~or coating inorganic substrates with carbides, nitrides or carbonitrides or mixtures thereof.
It has been found that inorganic substrates can be coated in a simple manner ~1ith carbides, nitrides or carb-nitrides or mixtures thereof, of iron, boron or silicon or of the transition metals of sub-groups 4-6 of the periodic table by direct thermal reaction of iron, boron, silicon or transition metals of s~lb-groups 4-6 of the periodic table or derivatives thereof with substances which act as sources of carbon and nitrogen? if desired in the presence of further additives, by using, as sources of carbon and nitrogen, at least one compound of the formula I or II
X - C - N or N ~ C - Xl - C - N
(I) (II) wherein X represents chlorine, -CN, -CH2-NH-CH2CN, -CH N(CH2CN)2, -CH2-N-CH2CH2-N(CH2CN)2, Y
1-6 carbon atoms, which can be substituted by halogen atoms, Rl -N\ or -N ~ CH2)m groups, an alkenyl group with 2-4 carbon atoms which can be substituted by halogen atoms or ~Rl -N groups, a cycloalkyl group with 3-6 carbon atoms or an
The present invention relates to a process ~or coating inorganic substrates with carbides, nitrides or carbonitrides or mixtures thereof.
It has been found that inorganic substrates can be coated in a simple manner ~1ith carbides, nitrides or carb-nitrides or mixtures thereof, of iron, boron or silicon or of the transition metals of sub-groups 4-6 of the periodic table by direct thermal reaction of iron, boron, silicon or transition metals of s~lb-groups 4-6 of the periodic table or derivatives thereof with substances which act as sources of carbon and nitrogen? if desired in the presence of further additives, by using, as sources of carbon and nitrogen, at least one compound of the formula I or II
X - C - N or N ~ C - Xl - C - N
(I) (II) wherein X represents chlorine, -CN, -CH2-NH-CH2CN, -CH N(CH2CN)2, -CH2-N-CH2CH2-N(CH2CN)2, Y
1-6 carbon atoms, which can be substituted by halogen atoms, Rl -N\ or -N ~ CH2)m groups, an alkenyl group with 2-4 carbon atoms which can be substituted by halogen atoms or ~Rl -N groups, a cycloalkyl group with 3-6 carbon atoms or an
- 2 -` , ' ., .
109L7~399 ~ryl group wi t~l G-10 caIbon a~oms, which can each be sub-~lt~ted by llalogen atoms, methyl groups or /~l -~ g~oups, an~ Xl represents an alkylene group with 1-10 R~
~arban at~m~, an alken~lene group with 2-4 carbon atoms, a phenylene or cyclohexylene group which can each be sub--jRl~tlt~ted by halogen atoms or -N\ groups, or a group of the for~:la R2 --~H,~CH2-- /CN or ~C-~>=c~N
CN CN
~nd ~ ~nd R2 ~ndependently of one another denote hydrogen or an alkyl group with 1-4 carbon atoms and m deno-tes an lnteger ~rom 4 to 7.
Compared to known methods, the process according to tha ln~entioll is di8tinguish~d, above all, by its simplicity ~nd 0con~my~ in that the elements carbon and nitrogen req~lred to fo~m ~he carbide8, nitride~ or carbonitrides or mixtures thereof,and,if desired other elements which influence the course of the reaction, such as hydrogen or halogen or both, can be ~ed to the reaction zone in a simple manner and in the desired ratios. Furthermore high deposition rates and smooth coatings of good to very good adhesion can be achieved in accordance with the process of the invention,regardless of the type of substrate and even at reaction temperatures below approx.
.
'-~04789~9 900C. A further advantage is that the process can in general be carried out at normal pressure or slightly reduced or slightly ele~ated pressure (approx. 700-800 mm Hg) which in many cases permits simplification of the apparatuses required to carry out the reaction.
The compounds of the formula I and II provide carbon and nitrogen, and where relevant hydrogen and/or halogen, in a reactive state, under the reaction conditions.
Alkyl, alkenyl, alkylene and alkenylene groups ' represented by X or Xl, or Rl and R2, can be straight-chain or branched. Halogen denotes fluorine, bromine or iodine, but especially chlorine.
Examples of unsubstituted alkyl groups X according to the definition are the methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, isopentyl and n-hexyl group.
If groups according to the definltion and represented ~r by X or Xl are substituted by -N \ groups, Rl and R2 preferably denote, independently of .. R2 one another, hydrogen or the meth ~ r ethyl group.
` Preferred substituents -N (CH2)m are those wherein m represents an integer from 4 to 6.
r, Preferred compounds of the formula I are those wherein X denotes -CH2-NH-CH2CN, -CH2-N~ CH2CN)2, -CH2-~N-CH2CH2-N---~CH2CN)2, an alkyl group with 1-6 carbon CH2CN ~ / 1 atoms which can be substituted by halogen atoms, -N
.;
:
1047~399 or - ~ CHz)m groups, an alken-yl group with 2-4 carbon atoms which can be substituted by halogen atoms or ~Rl -N~ groups, a cycloalkyl group with 3-6 carbon atoms or an aryl group with 6-10 carbon atoms which can each be substituted ~Rl by halogen atoms, methyl groups or -N\ groups, and Rl and . R2 R2 independently of one another represent hydrogenor an alkyl group with 1-4 carbon atoms and m represents an integer from 4 to 7.
According to a further preference, X represents an alkyl group with 1-4 carbon atoms which can be substituted by chlorine atoms or _N\ 1 groups, an alkenyl or chloroalkenyl group with 2-4 carbon atoms or a phenyl group which can ~e substituted by halogen atoms, methyl groups or _N\ 1 groups, and Rl and R2 independently of one another denote hydrogen or an alkyl group with 1 or 2 carbon atoms.
The compounds of the formula II which are used are advantageously those wherein Xl represents an unsubstituted alkylene group with 1-4 carbon atoms, an unsubstituted phenylene or cyclohexylene group or a group of the formula \C-C/
CN - ~
The use of acetonitrile, propionitrile, acrylonitrile, succinodinitrile, adipodinitrile or tetracyanoethylene as ,, ' : ' ', : - ~ . ,~' .
.
104789'~
compounds of the formula I or II is very particularly pre-ferred.
The compounds o~ the formula I and II are known or can be manufactured in a known manner. The following may be mentioned specifically as compounds of the formula I or II~
cyanogen chloride, cyanogen, bis-cyanomethylamine (iminodi-acetonitrile), tris-cyanomethyl-amine (nitrilotriacetonitrile), N,N,N',N'-tetrakis-(cyanomethyl)-ethylenediamine (ethylene-diamine-tetraacetonitrile), acetonitrile, monochloroaceto-nitrile, dichloroacetonitrile and trichloroacetonitrile, aminoacetonitrile, methylaminoacetonitrile, dimethylamino-acetonitrile, propionitrile, 3-chloropropionitrile, 3-bromo-propionitrile, 3-aminopropionitrile, 3-methylaminopropionitrile,
109L7~399 ~ryl group wi t~l G-10 caIbon a~oms, which can each be sub-~lt~ted by llalogen atoms, methyl groups or /~l -~ g~oups, an~ Xl represents an alkylene group with 1-10 R~
~arban at~m~, an alken~lene group with 2-4 carbon atoms, a phenylene or cyclohexylene group which can each be sub--jRl~tlt~ted by halogen atoms or -N\ groups, or a group of the for~:la R2 --~H,~CH2-- /CN or ~C-~>=c~N
CN CN
~nd ~ ~nd R2 ~ndependently of one another denote hydrogen or an alkyl group with 1-4 carbon atoms and m deno-tes an lnteger ~rom 4 to 7.
Compared to known methods, the process according to tha ln~entioll is di8tinguish~d, above all, by its simplicity ~nd 0con~my~ in that the elements carbon and nitrogen req~lred to fo~m ~he carbide8, nitride~ or carbonitrides or mixtures thereof,and,if desired other elements which influence the course of the reaction, such as hydrogen or halogen or both, can be ~ed to the reaction zone in a simple manner and in the desired ratios. Furthermore high deposition rates and smooth coatings of good to very good adhesion can be achieved in accordance with the process of the invention,regardless of the type of substrate and even at reaction temperatures below approx.
.
'-~04789~9 900C. A further advantage is that the process can in general be carried out at normal pressure or slightly reduced or slightly ele~ated pressure (approx. 700-800 mm Hg) which in many cases permits simplification of the apparatuses required to carry out the reaction.
The compounds of the formula I and II provide carbon and nitrogen, and where relevant hydrogen and/or halogen, in a reactive state, under the reaction conditions.
Alkyl, alkenyl, alkylene and alkenylene groups ' represented by X or Xl, or Rl and R2, can be straight-chain or branched. Halogen denotes fluorine, bromine or iodine, but especially chlorine.
Examples of unsubstituted alkyl groups X according to the definition are the methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, isopentyl and n-hexyl group.
If groups according to the definltion and represented ~r by X or Xl are substituted by -N \ groups, Rl and R2 preferably denote, independently of .. R2 one another, hydrogen or the meth ~ r ethyl group.
` Preferred substituents -N (CH2)m are those wherein m represents an integer from 4 to 6.
r, Preferred compounds of the formula I are those wherein X denotes -CH2-NH-CH2CN, -CH2-N~ CH2CN)2, -CH2-~N-CH2CH2-N---~CH2CN)2, an alkyl group with 1-6 carbon CH2CN ~ / 1 atoms which can be substituted by halogen atoms, -N
.;
:
1047~399 or - ~ CHz)m groups, an alken-yl group with 2-4 carbon atoms which can be substituted by halogen atoms or ~Rl -N~ groups, a cycloalkyl group with 3-6 carbon atoms or an aryl group with 6-10 carbon atoms which can each be substituted ~Rl by halogen atoms, methyl groups or -N\ groups, and Rl and . R2 R2 independently of one another represent hydrogenor an alkyl group with 1-4 carbon atoms and m represents an integer from 4 to 7.
According to a further preference, X represents an alkyl group with 1-4 carbon atoms which can be substituted by chlorine atoms or _N\ 1 groups, an alkenyl or chloroalkenyl group with 2-4 carbon atoms or a phenyl group which can ~e substituted by halogen atoms, methyl groups or _N\ 1 groups, and Rl and R2 independently of one another denote hydrogen or an alkyl group with 1 or 2 carbon atoms.
The compounds of the formula II which are used are advantageously those wherein Xl represents an unsubstituted alkylene group with 1-4 carbon atoms, an unsubstituted phenylene or cyclohexylene group or a group of the formula \C-C/
CN - ~
The use of acetonitrile, propionitrile, acrylonitrile, succinodinitrile, adipodinitrile or tetracyanoethylene as ,, ' : ' ', : - ~ . ,~' .
.
104789'~
compounds of the formula I or II is very particularly pre-ferred.
The compounds o~ the formula I and II are known or can be manufactured in a known manner. The following may be mentioned specifically as compounds of the formula I or II~
cyanogen chloride, cyanogen, bis-cyanomethylamine (iminodi-acetonitrile), tris-cyanomethyl-amine (nitrilotriacetonitrile), N,N,N',N'-tetrakis-(cyanomethyl)-ethylenediamine (ethylene-diamine-tetraacetonitrile), acetonitrile, monochloroaceto-nitrile, dichloroacetonitrile and trichloroacetonitrile, aminoacetonitrile, methylaminoacetonitrile, dimethylamino-acetonitrile, propionitrile, 3-chloropropionitrile, 3-bromo-propionitrile, 3-aminopropionitrile, 3-methylaminopropionitrile,
3-dimethylaminopropionitrile and 3-diethylaminopropionitrile, butyronitrile, 4-chlorobutyronitrile, 4-diethylaminobutyro-nitrile, capronitrile, isocapronitrile, oenanthonitrile, N-pyrrolidino-, N-piperidino- and hexamethyleneimino-aceto-nitrile, 4-(N-pyrrolidino)-, 4-(N-piperidino)- and 4-(N-hexamethyleneimino)-butyronitrile, acrylonitrile, a-meth-acrylonitrile, 2-chloroacrylonitrile, 3-vinylacrylonitrile, cyclopropanecarboxylic acid nitrile, cyclopentanecarboxylic acid nitrile, cyclohexanecarboxylic acid nitrile, chloro-cyclohexanecarboxylic acid nitrile, bromocyclohexanecar-boxylic acid nitrile or methylcyclohexanecarboxylic acid nitrile, 4-(N,N-dimethylamino)-cyclohexanecarboxylic acid nitrile, benzonitrile, 1- or 2-naphthonitrile, 2-, 3- or 4-chlorobenzonitrile, 4-bromobenzonitrile, o-, m- or p-tolu-nitrile, aminobenzonitrile, 4-dimethylaminobenzonitrile and .
.-' . ' ''' .
.
~ L047899
.-' . ' ''' .
.
~ L047899
4-diethylaminobenzo-nitrile, malodinitrile, chloromaleodinitrile, fumarodinitrile, succinodinitrile, glutarodinitrile, 3-methyl-glutarodinitrile, adipodinitrile, pimelodinitrile, decanoic acid dinitrile, dodecanoic acid dinitrile, undecanoic acid dinitrile, 2-methylene-glutarodinitrile (2,4-dicyano-1-butene), 3-hexenedicarboxylic acid dinitrile (1,4-dicyano-2-butene), phthalodinitrile, 4-chlorophthalodinitrile, 4-amino-phthalodinitrile, isophthalodinitrile, terephthalodinitrile, hexahydroterephthalodinitrile, tetracyanoethylene, 1,2-bis-(cyanomethyl)-benzene and 7,7,8,8-tetracyano-quinodimethane [2,5-cyclohexadiene-~1'a 4'a -dimalononitrile].
Examples of transition metals of sub~groups 4-6 of the periodic table which can be used in the process according to the invention are titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten and uranium.
Preferred elements are iron, uranium, tantalum, vanadium and tungsten, but especially boron, silicon and titanium.
The iron, boron and silicon and the transition metals of sub-groups 4-6 of the periodic table can be employed in any desired form, for example in the form of the elements.
However, they are-conveniently used in the form of derivatives, especially in the case of the transition metals according to the definition. Examples of suitable derivatives are hydrides, carbonyls, carbonyl-hydrides, organometallic com-' pounds and halides, such as silicon hydride (SiH4), titanium hydride (TiH2), zirconium hydride (ZrH2), boranes, chromium hexacarbonyl, molybdemlm hexacarbonyl and tungsten hexa-carbonyl, iron pentacarbonyl [Fe(CO)5], FeH2(CO)4, tetra-,.
,',: ~ :
.
,: :
' ' : ' ' ~.'' : ' .' ~ ' ' ~
1~ 47 8 9~
ethyltitanium, te~netllylsllane and tetraethyl~ e, Inethyl-dlchloro~llane~ ~richlorosil~le, methyl-tricllloro~llane, et~lyl-~rlchloro3ilane, trlmet~lylchloro~ilane, boron tric~oride, sllloon tetrac~oride, ti~anium dlbromlde, tit~nium trichlorlde, tltanlu~ tetrac~orlde and titanium tetrabromlde, zirconium tetr~chloride, vanadium trichlorlde and vanadium tetrachlorlde, nioblum pentachloride, t~ntalum pentachloride, chromlum trl-chlor~de, tungsten hexachloride and tungsten hexafluoride, Iron-~I chloride and lron Il~ chloride, uranium te trachlorlde an~ ~ra~ium hexafluorlde.
~ he hallde~, e~peclally the chlo~ldes, abo~e all tho~e Of boron~ sllicon and the tr~nsltion met~ls, are p~eferr~d.
Boron trlohlor~de, ~lllcon tetrachlorld~ and titan~um te~ra-~hlor~de are very par~ic~larly preferred.
~ ep~nding on the end use and/or the type of compound Of th~ formula ~ or II, it can be desira~le to carry out the re~c~on ln the presence of further Addltives~ such as hydro-~sn~ bydrogen chloride, ~tomic or molecular nltrogen or other ~o~pound~ which ae~ as sources of nltrogen or carbon or mixtures thereof under the reaction conditions. These sub-stances or compounds can contribute to the formation of the carbides, nitrides or carbonitrides or shift the equilibrium of the formation reaction more towards the nitrides or the carbides. Examples of such additional compounds which act as sources of nitrogen or carbon or mixtures thereof under the reaction conditions are methane, ethane, n-butane, N-methyl-- amine, N,N-diethylamine, ethylenediamine, benzene and ammonia.
The coating, according to the invention, of inorganic ,, , ~, . . . ~ . . . _ .
1047~9C~
substrates with carbides, nitrides or carbonitrides or mix-tures thereof can be carried out, within the scope of the definition, in accordance with any desired methods which are in themselves known.
One of the mos-t important processes is the chemical deposition from the gas phase, also referred to as the CVD
process (chemical vapour deposition). The reaction in the gas phase can be carried out wi-th application of heat or radiant energy. In this process, the iron, boron and sili-con or the transition metals, and the compounds of the formula I or II, are usually employed in the form of gaseous com-pounds. The reaction temperatures are in general between about 500 and 1,800C, preferably between 800 and 1,500C.
Hydrogen is preferably used as the reducing a~ent.
~n certain cases it can also be advantageous to use a carrier gas, such as argon, to transport the starting materials into the reaction zone.
According to another method, the substrates to be coated can also be covered with mixtures of materials, for example powder mixtures, or be mixed, and optionally compacted with other materials which contain all or - preferably - some of the starting materials required to form the carbides, nitrides or carbonitrides.
Thereafter, the whole is heated, preferably to temperatures of between 500 and 2,000C, the heating being carried out, in accordance with the composition of the mixture of materials, in the presence of the starting materials which are as yet lacking in the mixture, that is to say in the presence of a gaseous compound of the formula I or II or in the presence of _ 9 _ s ~: - - - .. . .
suitable derivatives, in the gaseous state, of iron, boron or silicon or of a transition metal.
The coating of the substrates with carbides, nitrides or carbonitrides or mixtures thereof can also be carried out by r~action of the starting materials in a plasma, for example by so-called plasma spraying. The plasma can be produced in any desired manner, for example by means of an electric arc, glow discharge or corona discharge. The plasma gases used are pre~erably argon or hydrogen.
Coatings according to the definition can furthermore be produced in accordance with the flame spraying process, -wherein hydrogen/oxygen or acetylene/oxygen flames are generally used.
A further method is to impregnate the substrate which . ls to be coated with a solution or suspension of a suitable j. derivative of iron, boron or silicon or of a transition metal and subsequently to react the impregnated material, at elevated temperatures, with a compound of the formula I or II.
. The process according to the invention is preferably carried out in accordance with the CVD technique.
Inbrganic substrates which can be coated with the aid of the process according to the invention are above all metallic and metalloid substrates, sintered metal carbides . and carbon materials of any desired typè, which can also con-tain incompletely pyrolysed constituents, such as glassy , (amorphous) carbon, partially graphitised carbon and graphite.
The process according to the invention is also suitable for coating ceramic substrates, glasses, oxides, nitrides and s -- 10 --~9 .
- ~ - ,,, ,, , ,... -~0478991 carbides.
Exarnples of metallic substrates are ferrous metals, such as steel and cast iron, t:itanium, and high-melting metals, such as tungsten, molybdenum, niobium, vanadium and tantalum. Examples of suitable me-talloids are boron and silicon, whilst suitable sintered metal carbides, that is to say sintered materials consisting of carbides of the transi-tion metals of sub-groups 4-6 of the periodic table and cobalt as the binder,are above all alloys of tungsten car-bide/cobalt, tungsten carbide/tantalum carbide/cobalt, tungsten carbide/titanium carbide/cobalt, tungsten carbide/
vanadium carbide/cobalt, tungsten carbide/titanium carbide/
tantalum carbide/cobalt, tungsten carbide/tantalum carbide/
niobium carbide/cobalt and tungsten carbide/titanium carbide/
tantalum carbide/niobium carbide/cobalt. Examples of suit-able ceramic substrates and oxides are porcelain, chamotte and clay materials, or aluminium oxide, SiO2 and zirconium dioxide. Examples of nitrides and carbides are Si3N4, SiC
and chromium carbides.
If carbon materials are used as substrates, a con-siderable improvement in the oxidation resistance and corrosion resistance of the carbon materials can in some cases be ~chieved by coating the materials in accordance with the invention.
The substrates can consist wholly or partially of one or more of the materials mentioned and can be in any desired form, for example in the form of powders, fibres, foils, filaments, machined articles or components of very diverse ~. .
. , 104~899~
types.
Depending on the choice of the starting materials and additives, the reaction temperatures or tne substrates, or both, carbides, nitridesJ carbonitrides or mixtures thereof -are formed in accordance with the process of the invention.
. The principal fields in which the process according to the invention is applied are: the surface improvement or surface hardening of metals and sintered metal carbides to increase the wear resistance and corrosion resistance, for example in the case of tool steel, cast iron, titanium, metal substrates containing -titanium, sheet tantalum, sheet vanadium and sheet iron and sintered metal carbides of the abovementioned type, such as WC-Co alloys, for example for use in lathe tools, press tools, punches, cutting tools and drawing dies, engine components, precision components for watches and textile machinery, rocket jets, corrosion-resistant apparatuses for the chemical industry, and the like; -the coating of carbon electrodes and graphite electrodes, of carbon fibres, including so-called "chopped fibres", to pro-~ect the fibres, to improve the adhesion and wettability by the metal matrix and to prevent undesired reactions between the carbon fibres and the metal matrix, of carbon-carbon composites, above all for turbine construction, of graphite seals and the like; the coating of ceramic materials or glasses, for example ceramic supports for catalysts and-filter glasses, and, finally, the coating of boron, silicon and tungsten fibres or filaments to achieve better wettability by the metal matrix, and to protect the fibres.
'','~
,, , , ' .
)4789~
Depen~ing on the choice of -the starting materials, additives ~ld reaction temperatures, carbides, nitrides, carbonitrides or mixtures -thereof are formed in accordance with the process of the invention.
Example 1 The experiments are carried out in a vertical CVD
reactor of Pyrex glass ("Pyrex" is a trade mark) which is closed at the top and bottom by means of a flange lid. The reaction gases are passed into the reactor through a spray-head, to achieve a uniform stream of gas. The ~emperature on the substrate is measured by means of a pyrometer. The compounds'of the formula I or II are - where necessary -vaporised in a vaporiser device inside or outside the reactor.
The substrate can be heated by resistance heating, high frequency heating or inductive heating or in a reactor externally heated by means of a furnace.
A steel wire of diameter 0.78 mm (1%
by weight of C, 0.1% by weight of Si, 0.25% by weight of Mn, 0.1~ by weight of V) is heated to 950C by resistance heating in an argon atmosphere in an apparatus of the type described ~bove. At this temperature, a gas mixture consisting of 95~ by volume of hydrogen, 2.4% by volume of argon, 1% by volume of titanium tetrachloride and 1.6% by volume of cyano-gen chloride is passed over the substrate in the course of 30 ' minutes, the total gas flow being 0.21 litre/minute [l/min.]
and the internal pressure in the reactor being 720 mm Hg.
After this period, a dark yellow layer has formed on the sub-strate. Layer thickness approx. 12 ~m; Vickers micro-hardness , ~ 13 ~
. .
~. . ' ... .. , .'.. ~.', .j .
HVo 015 = 2,270 kg/cm .
Example 2 A steel wire of 0.78 mm d~iameter is provided, by the CVD process, with a 6 ~m thick layer of chromium carbide.
This coated steel wire is then treated~by the method described in Example 1, for 2 hours at 950C/720 mm Hg, with a gas mix-ture consisting of 97% by volume of hydrogen, 1% by volume of titanium tetrachloride and 2% by volume of propionitrile (total gas flow 1.03 l/min~). A dark grey layer, approx.
30 ~m thick, having a micro-hardness HVo-025 = 2,280 kg/mm2, forms.
Examples 3 - 31 The Table I which follows lists further substrates which were coated in the manner described above.
.. . .
: - . ~ . , -., .
.. . . .
, , ' `I
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Example 32 .
A graphite rod of 2 mm diameter is heated by resistance heating to 950C in an argon atmosphere in an apparatus of the type described in Example 1. At this temperature, a gas mix-ture consisting of 97% by volume of hydrogen, 2% by volume of acetonitrile and 1% by volume of titanium te-trachloride is passed over the substrate for 2 hours, the total gas flow being 1.03 litre/minute [l/min.] and the internal pressure in the reactor being 720 mm Hg. After this time, a grey-violet, hard layer has formed on the graphite rod. The layer, which adheres very firmly, is 70 ~m thick and has a Vickers micro-hardness of HVo 01 > 4,000 kg/mm .
~ Example 33 -i~ A graphite rod of 2 mm diameter is heated to 950C in ~;
an argon atmosphere in an apparatus of the type described above.
At this temperature, a gas mixture consisting of 94.4% by volume of hydrogen, 2.3% by volume of argon, 1.4% by volume of titanium tetrachloride and 1.9% by volume of cyanogen chloride is passed over the substrate for 1 hour, the total gas flow being 0.21 l/min. and the internal pressure in the reactor ~; .
being 720 mm Hg. After this time, a grey, hard layer has formed on the graphite rod. The layer, which adheres very firmly, is 30 ~m thick and has a Vickers micro-hardness of s HVo-05 = 3,700 kg/mm .
Examples 34 - 46 Table II which follows lists further carbon materials which were coated in the manner described above:
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o o o a> o u~ o a~ o Dl
Examples of transition metals of sub~groups 4-6 of the periodic table which can be used in the process according to the invention are titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten and uranium.
Preferred elements are iron, uranium, tantalum, vanadium and tungsten, but especially boron, silicon and titanium.
The iron, boron and silicon and the transition metals of sub-groups 4-6 of the periodic table can be employed in any desired form, for example in the form of the elements.
However, they are-conveniently used in the form of derivatives, especially in the case of the transition metals according to the definition. Examples of suitable derivatives are hydrides, carbonyls, carbonyl-hydrides, organometallic com-' pounds and halides, such as silicon hydride (SiH4), titanium hydride (TiH2), zirconium hydride (ZrH2), boranes, chromium hexacarbonyl, molybdemlm hexacarbonyl and tungsten hexa-carbonyl, iron pentacarbonyl [Fe(CO)5], FeH2(CO)4, tetra-,.
,',: ~ :
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1~ 47 8 9~
ethyltitanium, te~netllylsllane and tetraethyl~ e, Inethyl-dlchloro~llane~ ~richlorosil~le, methyl-tricllloro~llane, et~lyl-~rlchloro3ilane, trlmet~lylchloro~ilane, boron tric~oride, sllloon tetrac~oride, ti~anium dlbromlde, tit~nium trichlorlde, tltanlu~ tetrac~orlde and titanium tetrabromlde, zirconium tetr~chloride, vanadium trichlorlde and vanadium tetrachlorlde, nioblum pentachloride, t~ntalum pentachloride, chromlum trl-chlor~de, tungsten hexachloride and tungsten hexafluoride, Iron-~I chloride and lron Il~ chloride, uranium te trachlorlde an~ ~ra~ium hexafluorlde.
~ he hallde~, e~peclally the chlo~ldes, abo~e all tho~e Of boron~ sllicon and the tr~nsltion met~ls, are p~eferr~d.
Boron trlohlor~de, ~lllcon tetrachlorld~ and titan~um te~ra-~hlor~de are very par~ic~larly preferred.
~ ep~nding on the end use and/or the type of compound Of th~ formula ~ or II, it can be desira~le to carry out the re~c~on ln the presence of further Addltives~ such as hydro-~sn~ bydrogen chloride, ~tomic or molecular nltrogen or other ~o~pound~ which ae~ as sources of nltrogen or carbon or mixtures thereof under the reaction conditions. These sub-stances or compounds can contribute to the formation of the carbides, nitrides or carbonitrides or shift the equilibrium of the formation reaction more towards the nitrides or the carbides. Examples of such additional compounds which act as sources of nitrogen or carbon or mixtures thereof under the reaction conditions are methane, ethane, n-butane, N-methyl-- amine, N,N-diethylamine, ethylenediamine, benzene and ammonia.
The coating, according to the invention, of inorganic ,, , ~, . . . ~ . . . _ .
1047~9C~
substrates with carbides, nitrides or carbonitrides or mix-tures thereof can be carried out, within the scope of the definition, in accordance with any desired methods which are in themselves known.
One of the mos-t important processes is the chemical deposition from the gas phase, also referred to as the CVD
process (chemical vapour deposition). The reaction in the gas phase can be carried out wi-th application of heat or radiant energy. In this process, the iron, boron and sili-con or the transition metals, and the compounds of the formula I or II, are usually employed in the form of gaseous com-pounds. The reaction temperatures are in general between about 500 and 1,800C, preferably between 800 and 1,500C.
Hydrogen is preferably used as the reducing a~ent.
~n certain cases it can also be advantageous to use a carrier gas, such as argon, to transport the starting materials into the reaction zone.
According to another method, the substrates to be coated can also be covered with mixtures of materials, for example powder mixtures, or be mixed, and optionally compacted with other materials which contain all or - preferably - some of the starting materials required to form the carbides, nitrides or carbonitrides.
Thereafter, the whole is heated, preferably to temperatures of between 500 and 2,000C, the heating being carried out, in accordance with the composition of the mixture of materials, in the presence of the starting materials which are as yet lacking in the mixture, that is to say in the presence of a gaseous compound of the formula I or II or in the presence of _ 9 _ s ~: - - - .. . .
suitable derivatives, in the gaseous state, of iron, boron or silicon or of a transition metal.
The coating of the substrates with carbides, nitrides or carbonitrides or mixtures thereof can also be carried out by r~action of the starting materials in a plasma, for example by so-called plasma spraying. The plasma can be produced in any desired manner, for example by means of an electric arc, glow discharge or corona discharge. The plasma gases used are pre~erably argon or hydrogen.
Coatings according to the definition can furthermore be produced in accordance with the flame spraying process, -wherein hydrogen/oxygen or acetylene/oxygen flames are generally used.
A further method is to impregnate the substrate which . ls to be coated with a solution or suspension of a suitable j. derivative of iron, boron or silicon or of a transition metal and subsequently to react the impregnated material, at elevated temperatures, with a compound of the formula I or II.
. The process according to the invention is preferably carried out in accordance with the CVD technique.
Inbrganic substrates which can be coated with the aid of the process according to the invention are above all metallic and metalloid substrates, sintered metal carbides . and carbon materials of any desired typè, which can also con-tain incompletely pyrolysed constituents, such as glassy , (amorphous) carbon, partially graphitised carbon and graphite.
The process according to the invention is also suitable for coating ceramic substrates, glasses, oxides, nitrides and s -- 10 --~9 .
- ~ - ,,, ,, , ,... -~0478991 carbides.
Exarnples of metallic substrates are ferrous metals, such as steel and cast iron, t:itanium, and high-melting metals, such as tungsten, molybdenum, niobium, vanadium and tantalum. Examples of suitable me-talloids are boron and silicon, whilst suitable sintered metal carbides, that is to say sintered materials consisting of carbides of the transi-tion metals of sub-groups 4-6 of the periodic table and cobalt as the binder,are above all alloys of tungsten car-bide/cobalt, tungsten carbide/tantalum carbide/cobalt, tungsten carbide/titanium carbide/cobalt, tungsten carbide/
vanadium carbide/cobalt, tungsten carbide/titanium carbide/
tantalum carbide/cobalt, tungsten carbide/tantalum carbide/
niobium carbide/cobalt and tungsten carbide/titanium carbide/
tantalum carbide/niobium carbide/cobalt. Examples of suit-able ceramic substrates and oxides are porcelain, chamotte and clay materials, or aluminium oxide, SiO2 and zirconium dioxide. Examples of nitrides and carbides are Si3N4, SiC
and chromium carbides.
If carbon materials are used as substrates, a con-siderable improvement in the oxidation resistance and corrosion resistance of the carbon materials can in some cases be ~chieved by coating the materials in accordance with the invention.
The substrates can consist wholly or partially of one or more of the materials mentioned and can be in any desired form, for example in the form of powders, fibres, foils, filaments, machined articles or components of very diverse ~. .
. , 104~899~
types.
Depending on the choice of the starting materials and additives, the reaction temperatures or tne substrates, or both, carbides, nitridesJ carbonitrides or mixtures thereof -are formed in accordance with the process of the invention.
. The principal fields in which the process according to the invention is applied are: the surface improvement or surface hardening of metals and sintered metal carbides to increase the wear resistance and corrosion resistance, for example in the case of tool steel, cast iron, titanium, metal substrates containing -titanium, sheet tantalum, sheet vanadium and sheet iron and sintered metal carbides of the abovementioned type, such as WC-Co alloys, for example for use in lathe tools, press tools, punches, cutting tools and drawing dies, engine components, precision components for watches and textile machinery, rocket jets, corrosion-resistant apparatuses for the chemical industry, and the like; -the coating of carbon electrodes and graphite electrodes, of carbon fibres, including so-called "chopped fibres", to pro-~ect the fibres, to improve the adhesion and wettability by the metal matrix and to prevent undesired reactions between the carbon fibres and the metal matrix, of carbon-carbon composites, above all for turbine construction, of graphite seals and the like; the coating of ceramic materials or glasses, for example ceramic supports for catalysts and-filter glasses, and, finally, the coating of boron, silicon and tungsten fibres or filaments to achieve better wettability by the metal matrix, and to protect the fibres.
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Depen~ing on the choice of -the starting materials, additives ~ld reaction temperatures, carbides, nitrides, carbonitrides or mixtures -thereof are formed in accordance with the process of the invention.
Example 1 The experiments are carried out in a vertical CVD
reactor of Pyrex glass ("Pyrex" is a trade mark) which is closed at the top and bottom by means of a flange lid. The reaction gases are passed into the reactor through a spray-head, to achieve a uniform stream of gas. The ~emperature on the substrate is measured by means of a pyrometer. The compounds'of the formula I or II are - where necessary -vaporised in a vaporiser device inside or outside the reactor.
The substrate can be heated by resistance heating, high frequency heating or inductive heating or in a reactor externally heated by means of a furnace.
A steel wire of diameter 0.78 mm (1%
by weight of C, 0.1% by weight of Si, 0.25% by weight of Mn, 0.1~ by weight of V) is heated to 950C by resistance heating in an argon atmosphere in an apparatus of the type described ~bove. At this temperature, a gas mixture consisting of 95~ by volume of hydrogen, 2.4% by volume of argon, 1% by volume of titanium tetrachloride and 1.6% by volume of cyano-gen chloride is passed over the substrate in the course of 30 ' minutes, the total gas flow being 0.21 litre/minute [l/min.]
and the internal pressure in the reactor being 720 mm Hg.
After this period, a dark yellow layer has formed on the sub-strate. Layer thickness approx. 12 ~m; Vickers micro-hardness , ~ 13 ~
. .
~. . ' ... .. , .'.. ~.', .j .
HVo 015 = 2,270 kg/cm .
Example 2 A steel wire of 0.78 mm d~iameter is provided, by the CVD process, with a 6 ~m thick layer of chromium carbide.
This coated steel wire is then treated~by the method described in Example 1, for 2 hours at 950C/720 mm Hg, with a gas mix-ture consisting of 97% by volume of hydrogen, 1% by volume of titanium tetrachloride and 2% by volume of propionitrile (total gas flow 1.03 l/min~). A dark grey layer, approx.
30 ~m thick, having a micro-hardness HVo-025 = 2,280 kg/mm2, forms.
Examples 3 - 31 The Table I which follows lists further substrates which were coated in the manner described above.
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- 19- 10~7899 - ,;- . . .
Example 32 .
A graphite rod of 2 mm diameter is heated by resistance heating to 950C in an argon atmosphere in an apparatus of the type described in Example 1. At this temperature, a gas mix-ture consisting of 97% by volume of hydrogen, 2% by volume of acetonitrile and 1% by volume of titanium te-trachloride is passed over the substrate for 2 hours, the total gas flow being 1.03 litre/minute [l/min.] and the internal pressure in the reactor being 720 mm Hg. After this time, a grey-violet, hard layer has formed on the graphite rod. The layer, which adheres very firmly, is 70 ~m thick and has a Vickers micro-hardness of HVo 01 > 4,000 kg/mm .
~ Example 33 -i~ A graphite rod of 2 mm diameter is heated to 950C in ~;
an argon atmosphere in an apparatus of the type described above.
At this temperature, a gas mixture consisting of 94.4% by volume of hydrogen, 2.3% by volume of argon, 1.4% by volume of titanium tetrachloride and 1.9% by volume of cyanogen chloride is passed over the substrate for 1 hour, the total gas flow being 0.21 l/min. and the internal pressure in the reactor ~; .
being 720 mm Hg. After this time, a grey, hard layer has formed on the graphite rod. The layer, which adheres very firmly, is 30 ~m thick and has a Vickers micro-hardness of s HVo-05 = 3,700 kg/mm .
Examples 34 - 46 Table II which follows lists further carbon materials which were coated in the manner described above:
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- - 23- ~047899 ,. -- . , .
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1~47899 Example 47 The experiment is carried out in a plasma reactor using a plasma torch of conventional construction [Model PJ 139 H of Messrs. Arcos, Brussels; torch rating: 7.8 kw (30 V, 260 A)].
The reactor is located in a water-cooled reaction chamber of stainless steel, sealed from the outside atmosphere. The plasma is produced by a DC light arc formed between the tung-sten cathode and the copper anode of the plasma torch. The cathode and anode are also water-cooled. Argon or hydrogen can be used as plasma gases. The reaction gases are introduced into the plasma beam with the aid of a carrier gas, through lateral bores in the outlet jet of the copper anode. The con-centration of the reaction gases in the stream of carrier gas is adjusted by means of thermostatically controllable vaporiser devices a~d flow regulators. The substrate, which under certain circumstances can be water-cooled, is at a distance of 1-5 cm in front of the outlet orifice of the plasma beam in the copper anode.
At the beginning of the experiment, the reaction chamber is evacuated, flushed and filled with argon. The plasma gas (argon, 90 mols/hour) is then introduced and the plasma flame is lit. A graphite substrate is located at a distance of 2 cm from the outlet orifice of the plasma beam and the reaction gases and the carrier gas are introduced into the plasma beam as follows: titanium tetrachloride: 0.02 mol/hour; carrier gas (hydrogen) for TiCI4: 1 mol/hour; acetonitrile: 0.05 mol/
hour; carrier gas (argon) for acetonitrile: 0.25 mol/hour.
The temperature of the plasma flame is above 3,000C; the .
, - - : - , : .
, 1~4789~
temperature of the substrate surface is approx. 2,500C.
After a reaction time of 15 minutes the plasma torch is s~itched off and the coated substrate is cooled in the gas-filled reaction chamber. A homogeneous, grey, well-adhering layer having a metallic gloss is obtained; thickness 4 ~m;
composition as determined by X-ray diffraction: TiC (lattice constant a = 4.33 ~).
Example 48 An aluminium oxide substrate is treated analogously to the method described in Example 47. The temperature of the substrate surface during coating is approx. 1,900C. A hard, relatively porous layer is obtained, which is built up of several zones of different colour. The outermost 7 grey layer has a lattice constant a = 4.31 ~.
.
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- - 23- ~047899 ,. -- . , .
.. , ,, .
1~47899 Example 47 The experiment is carried out in a plasma reactor using a plasma torch of conventional construction [Model PJ 139 H of Messrs. Arcos, Brussels; torch rating: 7.8 kw (30 V, 260 A)].
The reactor is located in a water-cooled reaction chamber of stainless steel, sealed from the outside atmosphere. The plasma is produced by a DC light arc formed between the tung-sten cathode and the copper anode of the plasma torch. The cathode and anode are also water-cooled. Argon or hydrogen can be used as plasma gases. The reaction gases are introduced into the plasma beam with the aid of a carrier gas, through lateral bores in the outlet jet of the copper anode. The con-centration of the reaction gases in the stream of carrier gas is adjusted by means of thermostatically controllable vaporiser devices a~d flow regulators. The substrate, which under certain circumstances can be water-cooled, is at a distance of 1-5 cm in front of the outlet orifice of the plasma beam in the copper anode.
At the beginning of the experiment, the reaction chamber is evacuated, flushed and filled with argon. The plasma gas (argon, 90 mols/hour) is then introduced and the plasma flame is lit. A graphite substrate is located at a distance of 2 cm from the outlet orifice of the plasma beam and the reaction gases and the carrier gas are introduced into the plasma beam as follows: titanium tetrachloride: 0.02 mol/hour; carrier gas (hydrogen) for TiCI4: 1 mol/hour; acetonitrile: 0.05 mol/
hour; carrier gas (argon) for acetonitrile: 0.25 mol/hour.
The temperature of the plasma flame is above 3,000C; the .
, - - : - , : .
, 1~4789~
temperature of the substrate surface is approx. 2,500C.
After a reaction time of 15 minutes the plasma torch is s~itched off and the coated substrate is cooled in the gas-filled reaction chamber. A homogeneous, grey, well-adhering layer having a metallic gloss is obtained; thickness 4 ~m;
composition as determined by X-ray diffraction: TiC (lattice constant a = 4.33 ~).
Example 48 An aluminium oxide substrate is treated analogously to the method described in Example 47. The temperature of the substrate surface during coating is approx. 1,900C. A hard, relatively porous layer is obtained, which is built up of several zones of different colour. The outermost 7 grey layer has a lattice constant a = 4.31 ~.
.
.
Claims (10)
1. A process for coating inorganic substrates with car-bides, nitrides or carbonitrides or mixtures thereof, of iron, boron or silicon or of the transition metals of sub-groups 4-6 of the periodic table by direct thermal reaction of iron, boron, silicon or transition metals of sub-groups 4-6 of the periodic table, or derivatives thereof, with substances which act as sources of carbon and nitrogen, characterised in that the sources of carbon and nitrogen used are at least one compound of the formula I or II
X - C ? N or N ? C - X1 - C ? N
(I) (II) wherein X represents chlorine, -CN, -CH2-NH-CH2CN, -CH2N?CH2CN)2, , an alkyl group with 1-6 carbon atoms, which can be substituted by halogen atoms or or groups, an alkenyl group with 2-4 carbon atoms,which can be substituted by halogen atoms or groups, a cycloalkyl group with 3-6 carbon atoms or an aryl group with 6-10 carbon atoms, which can each be substituted by halogen atoms, methyl groups or groups, and X1 represents an alkylene group with 1-10 carbon atoms, an alkenylene group with 2-4 carbon atoms, a phenylene or cyclo-hexylene group,which can each be substituted by halogen atoms or groups, or a group of the formula , or and R1 and R2 independently of one another denote hydrogen or an alkyl group with 1-4 carbon atoms and m denotes an integer from 4 to 7.
X - C ? N or N ? C - X1 - C ? N
(I) (II) wherein X represents chlorine, -CN, -CH2-NH-CH2CN, -CH2N?CH2CN)2, , an alkyl group with 1-6 carbon atoms, which can be substituted by halogen atoms or or groups, an alkenyl group with 2-4 carbon atoms,which can be substituted by halogen atoms or groups, a cycloalkyl group with 3-6 carbon atoms or an aryl group with 6-10 carbon atoms, which can each be substituted by halogen atoms, methyl groups or groups, and X1 represents an alkylene group with 1-10 carbon atoms, an alkenylene group with 2-4 carbon atoms, a phenylene or cyclo-hexylene group,which can each be substituted by halogen atoms or groups, or a group of the formula , or and R1 and R2 independently of one another denote hydrogen or an alkyl group with 1-4 carbon atoms and m denotes an integer from 4 to 7.
2. A process according to Claim 19 characterised in that compounds of the formula I, wherein X represents -CH2-NH-CH2CN, -CH2-N-(CH2CN)2, , an alkyl group with 1-6 carbon atoms, which can be substituted by halogen atoms or or groups, an alkenyl group with 2-4 carbon atoms,which can be substituted by halogen atoms or groups, a cycloalkyl group with 3-6 carbon atoms or an aryl group with 6-10 carbon atoms,which can each be substituted by halogen atoms, methyl groups or groups, and R1, R2 and m have the meaning indicated in Claim 1, are used.
3. A process according to Claim 1, characterised in that compounds of the formula I, wherein X represents an alkyl group with 1-4 carbon atoms,which can be substituted by chlorine atoms or groups, an alkenyl or chloroalkenyl group with 2-4 carbon atoms or a phenyl group,which can be substituted by halogen atoms, methyl groups or groups, and R1 and R2 independently of one another denote hydrogen or an alkyl group with 1 or 2 carbon atoms, are used.
4. A process according to Claim 1, characterised in that compounds of the formula II, wherein X1 represents an unsub-stituted alkylene group with 1-4 carbon atoms, an unsubstituted phenylene or cyclohexylene group or a group of the formula are used.
5. A process according to Claim 1, characterised in that acetonitrile, propionitrile, acrylonitrile, succinodinitrile, adipodinitrile or tetracyanoethylene are used.
6. A process according to Claim 1, characterised in that metallic or metalloid substrates are used.
7, A process according to Claim 1, characterised in that sintered metal carbide substrates are used.
8. A process according to Claim 1, characterised in that carbon materials are used as the substrates.
9. A process according to Claim 1, characterised in that the reaction is carried out in the presence of hydrogen, hydrogen chloride, atomic or molecular nitrogen or other compounds which act as sources of nitrogen or carbon or mixtures thereof under the reaction conditions, as further additives.
10. A process according to Claim 1, characterised in that the reaction is effected in the presence of a carrier gas.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH170474A CH593345A5 (en) | 1974-02-07 | 1974-02-07 | Depositing carbide, nitride and carbonitride coatings - on inorg. substrates by using cyano cpds. as sources of carbon and nitrogen |
| CH170374A CH589723A5 (en) | 1974-02-07 | 1974-02-07 | Depositing carbide, nitride and carbonitride coatings - on inorg. substrates by using cyano cpds. as sources of carbon and nitrogen |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1047899A true CA1047899A (en) | 1979-02-06 |
Family
ID=25688425
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA219,428A Expired CA1047899A (en) | 1974-02-07 | 1975-02-05 | Process for coating inorganic substrates with carbides, nitrides and/or carbonitrides |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS5753308B2 (en) |
| AT (1) | AT332697B (en) |
| CA (1) | CA1047899A (en) |
| FR (1) | FR2273080B1 (en) |
| GB (1) | GB1489102A (en) |
| SE (1) | SE410743B (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50124904A (en) * | 1974-03-20 | 1975-10-01 | ||
| GB2227755B (en) * | 1988-12-08 | 1993-03-10 | Univ Hull | A process for improving the wear and corrosion resistance of metallic components |
| EP1598456B1 (en) * | 2004-05-17 | 2008-11-12 | Bräcker AG | Ring traveller and method for producing the same. |
| DE102005049393B4 (en) * | 2005-10-15 | 2019-08-08 | Kennametal Widia Produktions Gmbh & Co. Kg | Method for producing a coated substrate body, substrate body with a coating and use of the coated substrate body |
| JP2011166160A (en) * | 2011-03-22 | 2011-08-25 | Tokyo Electron Ltd | Method of forming multilayer film |
| JP2022501514A (en) * | 2018-09-28 | 2022-01-06 | コーニング インコーポレイテッド | A low temperature method for depositing inorganic particles on a metal substrate and articles manufactured by this low temperature method. |
| CN109243654B (en) * | 2018-10-10 | 2022-10-18 | 镇江华核装备有限公司 | Preparation process of nuclear leakage emergency shielding clothes |
-
1975
- 1975-02-05 CA CA219,428A patent/CA1047899A/en not_active Expired
- 1975-02-06 SE SE7501315A patent/SE410743B/en not_active IP Right Cessation
- 1975-02-06 FR FR7503703A patent/FR2273080B1/fr not_active Expired
- 1975-02-06 AT AT92375A patent/AT332697B/en not_active IP Right Cessation
- 1975-02-07 JP JP1617175A patent/JPS5753308B2/ja not_active Expired
- 1975-02-07 GB GB534475A patent/GB1489102A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5753308B2 (en) | 1982-11-12 |
| SE7501315L (en) | 1975-08-08 |
| JPS50117809A (en) | 1975-09-16 |
| ATA92375A (en) | 1976-01-15 |
| DE2505009A1 (en) | 1975-08-14 |
| SE410743B (en) | 1979-10-29 |
| GB1489102A (en) | 1977-10-19 |
| FR2273080A1 (en) | 1975-12-26 |
| AT332697B (en) | 1976-10-11 |
| DE2505009B2 (en) | 1977-06-30 |
| FR2273080B1 (en) | 1977-09-16 |
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