Title of Invention	COMPOUND MATERIAL AND METHOD FOR ITS PRODUCTION
Abstract	Title: Compound material and method for its production. Compound material of a coated hart metal or cermet substrate body, upon which a sole or in the case of a multiple layer coating at least one layer with a thickness of 0.5 ?m to 25 ?m, preferably the outermost layer, contains an Al2O3 phase and a phase consisting of ZrO2 and/or HfO2. Characterized in that in the layer containing Al2O3 and a second phase of ZrO2 and/or HfO2 contains a third finely dispersed phase consisting of oxide, oxicarbide, oxinitride or oxicarbonitride of titanium and of individual crystallites of a size which is smaller than 1/100 of the crystallite size of the Al2O3 and the ZrO2 and /or HfO2 phases.

Title of Invention

COMPOUND MATERIAL AND METHOD FOR ITS PRODUCTION

Abstract

Title: Compound material and method for its production. Compound material of a coated hart metal or cermet substrate body, upon which a sole or in the case of a multiple layer coating at least one layer with a thickness of 0.5 ?m to 25 ?m, preferably the outermost layer, contains an Al2O3 phase and a phase consisting of ZrO2 and/or HfO2. Characterized in that in the layer containing Al2O3 and a second phase of ZrO2 and/or HfO2 contains a third finely dispersed phase consisting of oxide, oxicarbide, oxinitride or oxicarbonitride of titanium and of individual crystallites of a size which is smaller than 1/100 of the crystallite size of the Al2O3 and the ZrO2 and /or HfO2 phases.

Full Text	FORM - 2 Description Compound Material and Method Tor Its Production The invention pertains to a compound material made of a coated hard metal or cermet base body, on which the only layer, or in case of a multi-layered coating at least one layer which is 0.??m to 25?m thick, preferably the outermost layer, contains an Al2O3 phase and another phase which consists of ZrO2 and/or HfO2. The invention further pertains to a method for producing a coating containing a First Al2O3 phase and a second phase consisting of ZrO2 and/or HfO2 on a substrate body or on a substrate body coated with one or several layers, with the help of a CVD (Chemical Vapour Deposition) method at deposition temperatures between 900°C and 1000°C in the gas phase, which contains the necessary gases for deposition from the group AlC3, ZrCl4 ,HfCl4, CO2. H2, CH4 and N2 or inert gases, and under pressures from 10 to 100000 Pa Already from the document DE 27 36 982 AI a wear protection coating for moulded parts is described, especially tools, consisting of a moulded body, preferably made of hard metal, and one or several surface coatings, out of which at least one protective coating is made of a ceramic matrix in which another material is embedded The ceramic matrix and the embedded material clearly possess different thermal coefficients of expansion, so that the protective coating is covered by the finest possible micro-cracks As embedding material to be used in a ceramic matrix made of Al2O3, unstabilised and/or partly stabilised ZrO2 is suggested For producing such a coating according to the CVD method, aluminium trichloride, carbondioxide and hydrogen are introduced into the gas phase for formation of Al2O3, and zirconium tetrachloride and water vapour are introduced for formation of ZrO2 in a reaction container ai 1 l00°C Due to the difference in thickness between the resistant tetragonal modification above a conversion temperature of about 1l00°C and the resistant, monocitnic modification of the zirconium oxide below approx 11OO°C, in case of a corresponding phase conversion one gets a significant change in volume of the embedded zirconium oxide This result in, the fact, that with increasing volume of zirconium oxide, at be time the micro, in the deposited ceramic coating gets increased The DF. 28 25 009 CO- describes a hard-metal body with a thin, wear-resistant made of alutnmxum oxide, which entirely or at least to the extent of 85%, 2 consists of K-modification and the eventually remaining portion of a-modification forms on the surface regions or spots of a size of maximum 10 ?m. The aluminium oxide coating can additionally contain titanium, zirconium and/or hafnium. For producing this ceramic coating with the help of the CVD method, apart from H2, AlCl3, CO2 and CO some small quantities of 0.03 to 0 5% TiCl4 is added to the gas mixture. This addition however only exclusively or almost exclusively serves the purpose of formation of the K-aluminium oxide-phase. A further CVD method for deposition of Al2O3 and/or ZrC2 by using an additional reagent like hydrogen sulphide, is described in the document EP 0 523 021 Bl. The document DE 195 18 927 Al describes a coated cutting tool consisting of a sinter carbide substrate or ceramic substrate with a wear-resistant compound ceramic coating, which has two different oxide phases, e.g. made of Al2O3 and ZrO2, and additionally a doping agent which is selected from the group sulphur, selenium, tellurium, phosphorus, arsenic, antimony, bismuth or compounds of these mentioned elements. For producing this two-phased coating according to a CVD method, aluminium and zirconium chloride, carbondioxide with hydrogen as carrier and a H2S gas is conducted over the substrate body at a temperature approx. 700 to 1250°C and a pressure of 133 Pa to surrounding pressure, whereby the two-phased coating gets deposited with a doping agent. The document EP 0 786 536 Al describes a coated hard metal body with a 3 to 20 ?m thick aluminium oxide layer, which has been deposited by the CVD and/or PVD method and which should contain 0 005 to 0 5 percent by weight of chlorine Facultatively, in this layer there could be 0.5 to 10 percent by weight of Zr and/or Hf as well as 1 5 to 15 percent by weight of Ti The document EP 0 162 652 A2 describes a multi-layered coating on a hard metal substrate body with an inner layer, which consists of at least one carbide, nitride, carbonitride. carbo-oxinitride, oxinitride. boric nitride or boric carbonitride of titanium, and an outer multi-layered coating with a total thickness of 5 to 20 urn, which consists of several AI2O3 layers with respective thicknesses of 001 to 2 ??, out of which each consists of an Al2O3 -film, in which titanium oxide is dissolved or at least 30 percent by volume of titanium oxide coexists The layers are separated by intermediate layers of 0.1 to 2 ?? thickness each, which respectively consist of TiC, TiN, TiCN, TiCNO, TiNO, titanium oxides, Ti (BN), Ti (BNC), SiC. AIN and A1ON It is the task of this invention to improve the wear resistance of the already mentioned compound material. Particularly for application of this compound material as cutting tool for machining of material, one should aim for improvement of service life and efficiency -3a- Furthermore, it is the task of this invention to present a method for producing an improved compound material This task is fulfilled by the compound material as mentioned in claim I, which as per the invention has the special feature, that the coating containing the Al2O3 and a second phase of ZrO2 and/or HfO2, additionally has a third fine dispersive phase which consists of an oxide, oxicarbide, oxinitride or oxicarbonitride of titanium, with the exception of such a coating which has chlorine content of 0 005 to 0 5 percent by weight. The third phase could particularly be made of TiO2, TiO, Ti2O, Ti2O3, Ti (0, C), Ti(O, N) or Ti(O, C, N) or mixture phases of these which are referred to below generally as TiOx-phases The embedding of TiOx-compounds into the two-phased ceramic coating brings about a dispersion-strengthening effect which significantly improves the wear resistance of the coating. According to a special design form of the invention, the share of this third phase (TiOx) in the total quantity of the ceramic coating should be 0.2 or even preferably 0 6 to 5 mol%. preferably at least 1 mol% The molecular ratio of the Al2O3 phase to the ZrO2 phase, HfO2 phase or ZrO2/HfO2-phase, which could also be formed as an oxide mixture (Zr. Hf) O2, is adapted according to the requirement, i e purpose of application of the compound material It is generally known that aluminium oxide has a high degree of hardness and a low heal conductivity at 10000C. In case of application of the compound material as cutting tool, the heat generated during machining is therefore mainly conducted to the borings and only to a much lesser extent to the cutting tool, which reduces the danger of plastic deformations of the cutting edge Aluminium oxide is also oxidation resistant at high temperatures, the inclination towards wear with iron substances as well as the coefficient of friction is very low However, in case of deposition of pure Al2O3-coatings one has the problem, that the grain growth during deposition can be only controlled with great difficulties The ZrO2 or HfO2. which compared to AI2O, are more resistant to chemical reactions and have extraordinarily low frictional values vis-a-vis iron substances, are on the other hand softer than Al2O3, but however have the advantage that during common deposition with Al2O3 they reduce the crystallite growth of the Al2O3-phase and in the compound also reduce the coefficient of friction Besides, the ZrO2-and/or HfO2-portion in the Al2O3 coating increases their heat-insulating effect, as ZrO2 only has I/10 of the heat conductivity as compared to Al2O3 Depending on the purpose of application, during which one should be able to utilize better chemical inertness, improved heat insulation of the ZrO2 or HfO2 or the higher wear resistance of A12O3 against friction, one should select the corresponding ratio of both phases accordingly. Ideally, the ratio of Al2O3 phase with respect to the ZrO2-, HfO2- or ZrO2/ HfO2-phase should lie between 9/10 and 10/1, whereby the ZrO2 and HfO2 could be present in the monoclinical and/or tetragonal form The third, fine-crystalline phase, according to another version of the invention, has a size which is less than 1/100 of the size of the crystallite of the A12O3 and the ZrO2- or HfO2-phases. -5- According to a further version of the invention, the compound material coating is multi-layered and has at least one layer made of carbide, nitride, carbonitride of one of the elements of the IVa- to Vla-group of the period system. Here, as intermediate layer between the basic body and the outermost layer made of Al2O3/ZrO2 (if required replaced totally or partly by HfO2) /TiOx, one uses a coating of TiN and/or Ti (C, N). These layers prevent the danger of the relatively brittle ceramic coating from getting peeled off from the basic body. The thickness of the Al2O3/Zr02 or HfO2/TiOx layer should preferably be between 1 ?m and 10 ?m, particularly between 2 urn and 8 urn. The total thickness of coating should not exceed 25 ?m. In a special design form, the first layer deposited on the base body and made of a titanium nitride or titanium carbonitride has a thickness between 3 and 8 urn and the second layer made of Al2O3/ZrO2 or HfO2/TiOx has a thickness between 2 and 8 ?m, whereby this second layer is either the outer layer or on this second layer an external layer of TiN, ZrO2 or ZrCN with a thickness between 1 and 5 urn has been deposited. For producing the above described Al2O3- ZrO2- or HfO2- TiOx-layer, as per the invention the method as mentioned in claim 9 is suggested. For CVD deposition, deposition temperatures of between 900°C and 1000°C are selected. The temperature should not be below 900°C as, far as possible on account of the otherwise too low deposition rate, whereas the deposition temperatures of 1000°C should not be exceeded, as at high temperatures very thick depositions occur in the region of the edges of the compound material, which particularly lead to undesirable crumbling during application of the compound material as cutting tool. The pressure in the gas atmosphere which is composed of AICI3, ZrCl3, HfCl4, CO2, H2, CH4 and -6- N2 or inert gases, is 10 to 100000 Pa According to the invention, the gas phase contains 0 2 to 5 mol % TiCl4 With the exception of the portions of titanium chloride as per the invention in the gas phase, the CVD method is basically known from the state-of-the-art technology, e g. from the already cited document DF 195 18 927 Al. According fo a further design, the gas phase portion of the AlCl3 is 1 to 5 mol % and/or (he gas phase portion of ZrCl4 or HfCl4 is 0 2 to 5 mol %, in order to obtain the desired relative percentual shares of the AlO3-phase to the ZrO2- or HfO2-phase The gas phase pressure should ideally he below 10000 Pa. preferably 8000 Pa For deposition of a multi-layered coating on a hard meial base body, which had a composition of 94 M% WC. rest Co, a CVD method with a gas phase temperature of 1000°C was selected The pressure of the respective gas phase was 8000 Pa In a first design example, on the mentioned hard metal body a subsequent layer of TiN. Ti (C. N) and the described AlO3/ZrO2/TiO-outer layer was applied The individual layer thicknesses as well as the gases used can be obtained from the following table Individual layer Thickness (?m) Gases used TiN 2.0 H2, N2l TiCl4 Ti(C, N) 4 1 H2, N2, CH4, TiCl4 Al2O3/Zr02/TiO 8 1 H2, CO2, AlCl3, TiCl4, CH4, ZrCl4, Total thickness 14 2 The gas phase composition in case of deposition of outer layer consisted of 10 1 AlCl3, 2 5 1 ZrCl4, 161 TiCl4. 20 HCO2. 40 1 N2. 320 1 H2 and 1 5 1 CH4, The layer structure can be obtained in fig. I which-shows a REM fractured structure picture. As one can see from the enlarged REM-structural image of the outer layer, as shown in fig. 2, the outer layer had Al2O3 - portions appearing as dark phases. ZrO2 portions appearing as bright phases, as well as a TiOX phase which can be seen as white dots. This phase has a crystallite size which is lesser than 1/100 of the crystallite size of both the other phases of Al2O3; and ZrO;. ¦ As a comparison to this, on a substrate body which similarly has a composition 94 M% WC. 6 M% Co. the following layer sequence was applied. Individual layer Thickness (urn) Gases used TiN 2.0 . H2, N2, TiCL, Ti(C, N). 4.0 H2, N2, CH4, TiCl4 Al2O3 7.6 H2, CO2, A1C13, Total thickness 13.6 Such a layer sequence with an Al2O3 outer layer is known from the state-of-the-art technology. Such compound bodies in the form of indexable inserts with a SNUN120412-geometry conforming to the layer composition according to the above tables, have been used for turning a shaft of grey casting of the type GG25 under the following cutting conditions. Cutting speed vc = 400 m/min Cutting depth ap = 2.5 mm Feed f=0.31 mm/rotation Wear VB = 0.5 mm With the indexable inserts known in the state-of-the-art technology, which have an Al2O3 outer layer, one can achieve service lives of approx. 4 min on an average. The indexable inserts coated as per the invention with Al2O3/ZrO2/TiOx-outer layer however achieved cutting lives of 13.7 min under the mentioned cutting condition. This means that the cutting insert as per the invention possesses a significantly improved wear resistance. In a farther application example, indexable inserts with a coating known in the state-of-the-art technology and a coating as per the invention were used for milling. The cutting inserts had the geometry RDMW1605. As substrate bodies here, similarly hard metal body with 94 M% WC and 6 M%Co served the purpose. The individual layers known from the state-of-the-art technology were as follows: Individual layer Thickness (?m) Gases used TiN 1.5 H2, N2, TiCl4 Ti (C, N) 2.8 H2, CH3CN, TiCl4 A12O3 2.3 H2, CO2, AlCl3, Total thickness 6.6 The coating as per the invention was deposited as follows under gas phase temperatures of 980°C: Individual layer Thickness (?m) Gases used TiN 1.2 H2. N2,TiCl4 Ti(C,N) 3.0 H2, CH3CN, TiCl4 Al2O3/ZrO2/TiOx 2.6 H2, CO2, AlCl3, TiCl4, CH4, N2. ZrCl4 Toial thickness 6.8 Here additionally N2 was introduced in the gas phase in a quantity of 20 1. The series of indexable inserts manufactured according to the state-of-the-art technology with an exterior Al2O3 coating as well as a series of indexable inserts with coating as per the invention were used for plain milling of a work piece from a 56NiCrMoV7 material with a strength of 1300 N/mm2 under the following cutting conditions: Cutting speed vc-3l5m/min Cutting depth ap - 0.5 mm Gripping width ae - 67.2 mm Feed fz = 0.31 mm/tboth Wear VB = 0.3 mm The running length for cutting which could be achieved with the cutting inserts as per the state-of-the-art technology amounted to 4000 mm on an average, whereas cutting inserts as per the invention achieved an average running length of 13000 mm. Even here one can see more than a three-fold higher life strength. Instead of hard metal base bodies, one can also use cermets having known composition. Similarly, for special cases of application, on the ceramic outer layer as per the invention an additional covering layer of ZrCN. HfCN and/or ZrO2, HfO2 or TiN can be applied. In a further application example, indexable inserts with a coating known as per the state-of-the-art technology and the coating as per the invention were used for milling. The cutting inserts had the geometry RDMW 1605. As substrate body here, similarly one used a hard metal body with 94 M% WC and 6 M% Co The individual layers known as per the state-of-the-art technology were as follows Individual layer Thickness (?m) Gases used TiN 1.5 H2, N2, TiCl4 Ti(C. N) 4 8 H, CH3CN, TiCl4 Al2O3 5 3 H2, CO2, A1Cl4, Total thickness 116 The coating as per the invention was deposited as follows under the gas phase temperature of 9800C. Individual layer Thickness (?m) Gases used TiN , 12 H2. N;, TiCl, Ti (C. N) 4.8 H2, CH3CN, TiCl4, Al2O3/Zr02/Ti0, 6.0 H2. CO2, AlCl3, TiCl4, CH4, HfCl4 Total thickness 12 0 The series of indexable inserts manufactured in a design form known as per the state-of-the-art technology with an outer Al2O3 coating, as well as a series of indexable inserts with a coating as per the invention were used for plain milling of a work piece from a GG25 material (HB = 180 - 240) under the following cutting condition: Cutting speed vc = 570 m/min Cutting depth ap = 2.0 mm Gripping width ae -- 62.5 mm I-eed fz = 0.20 mm/tooth Wear VB - 0 .3 mm The running length per cutting which could be achieved with cutting inserts known from the state-of-the-art technology was on an average 5000 mm, whereas cutting inserts as per the invention achieved on an average a running length of 15000 mm. Here too one could see a three-fold higher endurance strength. In a further application example, indexable inserts with a coating known in the state-of-the-art technology and a coating as per the invention were used for milling. The cutting inserts had . the geometry RDMW 1605. As substrate body here, one similarly used a hard metal body with 94 M% WC and 6 M% Co. The individual layers known in the state-of-the-art technology were as follows: Individual layer Thickness (?m) Gases used TiN 1.0 H2, N2, TiCl4 Ti (C. N) 4.9 H2, CH3CN, TiCl4 Al2O3 6.3 H2, CO2, AlCl3 Total thickness 12.2 The coating as per the invention was deposited as follows under a gas phase temperature of 980°C: Individual layer Thickness (?m) Gases used TiN 1.5 H2, N2, TiCl4 Ti (C, N) 4.1 H2, CH3CN, TiCl4 A12O3/(Zr, Hf) O2/TiOx 7.0 H2, CO2, AlCl3, TiCl4, CH4, N2, ZrCl4, HfCl4 Total thickness 12.6 The series of indexable inserts manufactured in a design form known from the state-of-the-art technology with an outer Al2O3 coating, as well as the series of indexable inserts with the coating as per the invention were used for plain milling of a work piece of GGG70 material (HB = 250 - 300) under the following cutting condition: Cutting speed vc - 350 m/min Cutting depth ap = 2.0 mm Gripping width ae = 25.0 mm Feed fz = 0.25 mm/tooth Wear VB = 0.5 mm The running length per cutting with the cutting inserts known in the state-of-the-art technology amounted to 1500 mm on an average, whereas cutting inserts as per the invention achieved on an average a running length of 4000 mm. As long as the compound body is designed as cutting inserts, these are suitable for turning, milling, here particularly high speed milling. -13-WE CLAIM Compound material of a coated hard metal or cermet substrate body, upon which a sole or in the case of a multiple layer coating at least one layer with a thickness of 0.5 ?m to 25 ?m, preferably the outermost layer, contains an AI2O3, phase and a phase consisting of ZrO2 and/or HfO2 characterized in that in the layer containing Al2O3 and a second phase of ZrO2 and/or HfO2 contains a third finely dispersed phase consisting of oxide, oxicarbide, oxinitride or oxicarbonitride of titanium and of individual crystallites of a size which is smaller than 1/100 of the crystallite size of the AI2O3 and the ZrO2 and/or HfO2 phases. Compound material as claimed in claim 1, wherein the third phase consists of TiO2, TiO, Ti2O, Ti2O3, Ti (O, C), Tl (O, N) or Ti (O, C, N) or mixture phases of these. Compound material as claimed in claim 1 or 2, wherein the portion of the third phase with respect to the total quantity of the layer should be 0.2 preferably 0.6 to 5 mot%, further preferably at least 1 mol% and the molecular ratio of the AI2O3-phase with respect to the Zr02-and/or HfOrphase lies between 9/10 and 10/1, whereby the ZrO2 and/or HfO2 is present in monoclinical and/or tetragonal form. Compound material as claimed in claim 1 or 3, wherein the third fine crystalline phase consists of individual crystallites having a size which is smaller than 1/100 of the size of the crystallites of the A12O3- and the ZrO^-and/or HfO2-phases. Compound material as claimed in claim 1 or 4, wherein The coating is mufti-layered and at least one layer is made of a carbide, nitride, carbonitrade of one of the elements of the Iva-to Via-group of the period system. -14- Compound material as claimed is claim 5, Where in there is a layer sequence deposited on the base body made of TiN, Ti (C, N) and an outer layer Al2O3,/ZrO2 and/or HfO2/TiOx with TiOx = TiO2, TiO, Ti2O, TiO3. Ti (O, C). Ti (0. N) or Ti (0, C. N) or mixture phases of these. Compound material as cleimed one of the claims 1 or 6, Wherein the thickness of the Al2O3/ZrO2 and/or HfO/TiC3-layer lies between 1 ?m and 10 ?m, preferably between 2 urn and 8 ?m, and/or the entire thickness of the coating should not exceed 25 ?m. Compound material as claimed in one of the claims 5 to 7. Wherein the first layer deposited on the base body has a thickness between 3 ?m and 8 ?m and the second layer made of Al2O3/ ZrO2 and/or HfO2/TiOx has a thickness between 2 ?m and 8 ?m, whereby this second layer is cither the outer layer or, on this second layer an outer layer made of TiN, ZrO2. HfO2, ZrCN or HfCN with a thickness between 1 ?m and 5 ?m has been deposited. Method for production of a layer containing a first phase of A12O3 and a second phase of ZrO2 and/or HfO2, on a substrate body or on a substrate body coated with one or several layers with the help of a CVD- (Chemical Vapour Deposition) method,at deposition temperatures between 900°C and 1000°C in the gas phase, which contains the gases necessary for deposition from the group Al2O3. ZrCl4, HfCl4, CO2, H2, CH4 and N2 or inert gases, and under pressures of 10 to 100000 Pa. in which the gas phase contains 0.2 to 5 mol % of TiCl4. Method as claimed claim 9. wherein the gas phase portion of the AlCl3 is between 1 to 5 mol % and/or the gas phase portion of the ZrCl4 and/or HlCl4 is between 0.2 and 5 mol %. Method as claimed in 9 or 10, Wherein the gas phase pressure Title: Compound material and method for its production. Compound material of a coated hart metal or cermet substrate body, upon which a sole or in the case of a multiple layer coating at least one layer with a thickness of 0.5 ?m to 25 ?m, preferably the outermost layer, contains an Al2O3 phase and a phase consisting of ZrO2 and/or HfO2. Characterized in that in the layer containing Al2O3 and a second phase of ZrO2 and/or HfO2 contains a third finely dispersed phase consisting of oxide, oxicarbide, oxinitride or oxicarbonitride of titanium and of individual crystallites of a size which is smaller than 1/100 of the crystallite size of the Al2O3 and the ZrO2 and /or HfO2 phases.

Full Text

FORM - 2

Description Compound Material and Method Tor Its Production
The invention pertains to a compound material made of a coated hard metal or cermet base body, on which the only layer, or in case of a multi-layered coating at least one layer which is 0.??m to 25?m thick, preferably the outermost layer, contains an Al2O3 phase and another phase which consists of ZrO2 and/or HfO2.
The invention further pertains to a method for producing a coating containing a First Al2O3 phase and a second phase consisting of ZrO2 and/or HfO2 on a substrate body or on a substrate body coated with one or several layers, with the help of a CVD (Chemical Vapour Deposition) method at deposition temperatures between 900°C and 1000°C in the gas phase, which contains the necessary gases for deposition from the group AlC3, ZrCl4 ,HfCl4, CO2. H2, CH4 and N2 or inert gases, and under pressures from 10 to 100000 Pa
Already from the document DE 27 36 982 AI a wear protection coating for moulded parts is described, especially tools, consisting of a moulded body, preferably made of hard metal, and one or several surface coatings, out of which at least one protective coating is made of a ceramic matrix in which another material is embedded The ceramic matrix and the embedded material clearly possess different thermal coefficients of expansion, so that the protective coating is covered by the finest possible micro-cracks As embedding material to be used in a ceramic matrix made of Al2O3, unstabilised and/or partly stabilised ZrO2 is suggested For producing such a coating according to the CVD method, aluminium trichloride, carbondioxide and hydrogen are introduced into the gas phase for formation of
Al2O3, and zirconium tetrachloride and water vapour are introduced for formation of ZrO2 in a reaction container ai 1 l00°C Due to the difference in thickness between the resistant tetragonal modification above a conversion temperature of about 1l00°C and the resistant, monocitnic modification of the zirconium oxide below approx 11OO°C, in case of a corresponding phase conversion one gets a significant change in volume of the embedded zirconium oxide This result in, the fact, that with increasing volume of zirconium oxide, at be time the micro, in the deposited ceramic coating gets increased
The DF. 28 25 009 CO- describes a hard-metal body with a thin, wear-resistant made of alutnmxum oxide, which entirely or at least to the extent of 85%,

2
consists of K-modification and the eventually remaining portion of a-modification forms on the surface regions or spots of a size of maximum 10 ?m. The aluminium oxide coating can additionally contain titanium, zirconium and/or hafnium. For producing this ceramic coating with the help of the CVD method, apart from H2, AlCl3, CO2 and CO some small quantities of 0.03 to 0 5% TiCl4 is added to the gas mixture.
This addition however only exclusively or almost exclusively serves the purpose of formation of the K-aluminium oxide-phase.
A further CVD method for deposition of Al2O3 and/or ZrC2 by using an additional reagent like hydrogen sulphide, is described in the document EP 0 523 021 Bl.
The document DE 195 18 927 Al describes a coated cutting tool consisting of a sinter carbide substrate or ceramic substrate with a wear-resistant compound ceramic coating, which has two different oxide phases, e.g. made of Al2O3 and ZrO2, and additionally a doping agent which is selected from the group sulphur, selenium, tellurium, phosphorus, arsenic, antimony, bismuth or compounds of these mentioned elements. For producing this two-phased coating according to a CVD method, aluminium and zirconium chloride, carbondioxide with hydrogen as carrier and a H2S gas is conducted over the substrate body at a temperature approx. 700 to 1250°C and a pressure of 133 Pa to surrounding pressure, whereby the two-phased coating gets deposited with a doping agent.

The document EP 0 786 536 Al describes a coated hard metal body with a 3 to 20 ?m thick aluminium oxide layer, which has been deposited by the CVD and/or PVD method and which should contain 0 005 to 0 5 percent by weight of chlorine Facultatively, in this layer there could be 0.5 to 10 percent by weight of Zr and/or Hf as well as 1 5 to 15 percent by weight of Ti
The document EP 0 162 652 A2 describes a multi-layered coating on a hard metal substrate body with an inner layer, which consists of at least one carbide, nitride, carbonitride. carbo-oxinitride, oxinitride. boric nitride or boric carbonitride of titanium, and an outer multi-layered coating with a total thickness of 5 to 20 urn, which consists of several AI2O3 layers with respective thicknesses of 001 to 2 ??, out of which each consists of an Al2O3 -film, in which titanium oxide is dissolved or at least 30 percent by volume of titanium oxide coexists The layers are separated by intermediate layers of 0.1 to 2 ?? thickness each, which respectively consist of TiC, TiN, TiCN, TiCNO, TiNO, titanium oxides, Ti (BN), Ti (BNC), SiC. AIN and A1ON
It is the task of this invention to improve the wear resistance of the already mentioned compound material. Particularly for application of this compound material as cutting tool for machining of material, one should aim for improvement of service life and efficiency

-3a-
Furthermore, it is the task of this invention to present a method for producing an improved compound material
This task is fulfilled by the compound material as mentioned in claim I, which as per the invention has the special feature, that the coating containing the Al2O3 and a second phase of ZrO2 and/or HfO2, additionally has a third fine dispersive phase which consists of an oxide, oxicarbide, oxinitride or oxicarbonitride of titanium, with the exception of such a coating which has chlorine content of 0 005 to 0 5 percent by weight. The third phase could particularly be made of TiO2, TiO, Ti2O, Ti2O3, Ti (0, C), Ti(O, N) or Ti(O, C, N) or mixture phases of these which are referred to below generally as TiOx-phases The embedding of TiOx-compounds into the two-phased ceramic coating brings about a dispersion-strengthening effect which significantly improves the wear resistance of the coating.

According to a special design form of the invention, the share of this third phase (TiOx) in the total quantity of the ceramic coating should be 0.2 or even preferably 0 6 to 5 mol%. preferably at least 1 mol% The molecular ratio of the Al2O3 phase to the ZrO2 phase, HfO2 phase or ZrO2/HfO2-phase, which could also be formed as an oxide mixture (Zr. Hf) O2, is adapted according to the requirement, i e purpose of application of the compound material It is generally known that aluminium oxide has a high degree of hardness and a low heal conductivity at 10000C. In case of application of the compound material as cutting tool, the heat generated during machining is therefore mainly conducted to the borings and only to a much lesser extent to the cutting tool, which reduces the danger of plastic deformations of the cutting edge Aluminium oxide is also oxidation resistant at high temperatures, the inclination towards wear with iron substances as well as the coefficient of friction is very low However, in case of deposition of pure Al2O3-coatings one has the problem, that the grain growth during deposition can be only controlled with great difficulties The ZrO2 or HfO2. which compared to AI2O, are more resistant to chemical reactions and have extraordinarily low frictional values vis-a-vis iron substances, are on the other hand softer than Al2O3, but however have the advantage that during common deposition with Al2O3 they reduce the crystallite growth of the Al2O3-phase and in the compound also reduce the coefficient of friction Besides, the ZrO2-and/or HfO2-portion in the Al2O3 coating increases their heat-insulating effect, as ZrO2 only has I/10 of the heat conductivity as compared to Al2O3 Depending on the purpose of application, during which one should be able to utilize better chemical inertness, improved heat insulation of the ZrO2 or HfO2 or the higher wear resistance of A12O3 against friction, one should select the corresponding ratio of both phases accordingly. Ideally, the ratio of Al2O3 phase with respect to the ZrO2-, HfO2- or ZrO2/ HfO2-phase should lie between 9/10 and 10/1, whereby the ZrO2 and HfO2 could be present in the monoclinical and/or tetragonal form
The third, fine-crystalline phase, according to another version of the invention, has a size which is less than 1/100 of the size of the crystallite of the A12O3 and the ZrO2- or HfO2-phases.

-5-
According to a further version of the invention, the compound material coating is multi-layered and has at least one layer made of carbide, nitride, carbonitride of one of the elements of the IVa- to Vla-group of the period system. Here, as intermediate layer between the basic body and the outermost layer made of Al2O3/ZrO2 (if required replaced totally or partly by HfO2) /TiOx, one uses a coating of TiN and/or Ti (C, N). These layers prevent the danger of the relatively brittle ceramic coating from getting peeled off from the basic body.
The thickness of the Al2O3/Zr02 or HfO2/TiOx layer should preferably be between 1 ?m and 10 ?m, particularly between 2 urn and 8 urn. The total thickness of coating should not exceed
25 ?m.
In a special design form, the first layer deposited on the base body and made of a titanium nitride or titanium carbonitride has a thickness between 3 and 8 urn and the second layer made of Al2O3/ZrO2 or HfO2/TiOx has a thickness between 2 and 8 ?m, whereby this second layer is either the outer layer or on this second layer an external layer of TiN, ZrO2 or ZrCN with a thickness between 1 and 5 urn has been deposited.
For producing the above described Al2O3- ZrO2- or HfO2- TiOx-layer, as per the invention the method as mentioned in claim 9 is suggested. For CVD deposition, deposition temperatures of between 900°C and 1000°C are selected. The temperature should not be below 900°C as, far as possible on account of the otherwise too low deposition rate, whereas the deposition temperatures of 1000°C should not be exceeded, as at high temperatures very thick depositions occur in the region of the edges of the compound material, which particularly lead to undesirable crumbling during application of the compound material as cutting tool. The pressure in the gas atmosphere which is composed of AICI3, ZrCl3, HfCl4, CO2, H2, CH4 and

-6-
N2 or inert gases, is 10 to 100000 Pa According to the invention, the gas phase contains 0 2 to 5 mol % TiCl4 With the exception of the portions of titanium chloride as per the invention in the gas phase, the CVD method is basically known from the state-of-the-art technology, e g. from the already cited document DF 195 18 927 Al.
According fo a further design, the gas phase portion of the AlCl3 is 1 to 5 mol % and/or (he gas phase portion of ZrCl4 or HfCl4 is 0 2 to 5 mol %, in order to obtain the desired relative percentual shares of the AlO3-phase to the ZrO2- or HfO2-phase The gas phase pressure should ideally he below 10000 Pa. preferably 8000 Pa For deposition of a multi-layered coating on a hard meial base body, which had a composition of 94 M% WC. rest Co, a CVD method with a gas phase temperature of 1000°C was selected The pressure of the respective gas phase was 8000 Pa
In a first design example, on the mentioned hard metal body a subsequent layer of TiN. Ti (C. N) and the described AlO3/ZrO2/TiO-outer layer was applied The individual layer thicknesses as well as the gases used can be obtained from the following table
Individual layer Thickness (?m) Gases used
TiN 2.0 H2, N2l TiCl4
Ti(C, N) 4 1 H2, N2, CH4, TiCl4
Al2O3/Zr02/TiO 8 1 H2, CO2, AlCl3,
TiCl4, CH4, ZrCl4,
Total thickness 14 2
The gas phase composition in case of deposition of outer layer consisted of 10 1 AlCl3, 2 5 1 ZrCl4, 161 TiCl4. 20 HCO2. 40 1 N2. 320 1 H2 and 1 5 1 CH4, The layer structure can be

obtained in fig. I which-shows a REM fractured structure picture. As one can see from the enlarged REM-structural image of the outer layer, as shown in fig. 2, the outer layer had Al2O3 - portions appearing as dark phases. ZrO2 portions appearing as bright phases, as well as a TiOX phase which can be seen as white dots. This phase has a crystallite size which is lesser than 1/100 of the crystallite size of both the other phases of Al2O3; and ZrO;.
¦ As a comparison to this, on a substrate body which similarly has a composition 94 M% WC. 6 M% Co. the following layer sequence was applied.
Individual layer Thickness (urn) Gases used
TiN 2.0 . H2, N2, TiCL,
Ti(C, N). 4.0 H2, N2, CH4, TiCl4
Al2O3 7.6 H2, CO2, A1C13,
Total thickness 13.6

Such a layer sequence with an Al2O3 outer layer is known from the state-of-the-art technology. Such compound bodies in the form of indexable inserts with a SNUN120412-geometry conforming to the layer composition according to the above tables, have been used for turning a shaft of grey casting of the type GG25 under the following cutting conditions.
Cutting speed vc = 400 m/min
Cutting depth ap = 2.5 mm
Feed f=0.31 mm/rotation
Wear VB = 0.5 mm
With the indexable inserts known in the state-of-the-art technology, which have an Al2O3 outer layer, one can achieve service lives of approx. 4 min on an average. The indexable inserts coated as per the invention with Al2O3/ZrO2/TiOx-outer layer however achieved cutting lives of 13.7 min under the mentioned cutting condition. This means that the cutting insert as per the invention possesses a significantly improved wear resistance.
In a farther application example, indexable inserts with a coating known in the state-of-the-art technology and a coating as per the invention were used for milling. The cutting inserts had the geometry RDMW1605. As substrate bodies here, similarly hard metal body with 94 M% WC and 6 M%Co served the purpose. The individual layers known from the state-of-the-art technology were as follows:
Individual layer Thickness (?m) Gases used
TiN 1.5 H2, N2, TiCl4
Ti (C, N) 2.8 H2, CH3CN, TiCl4
A12O3 2.3 H2, CO2, AlCl3,
Total thickness 6.6
The coating as per the invention was deposited as follows under gas phase temperatures of 980°C:

Individual layer Thickness (?m) Gases used
TiN 1.2 H2. N2,TiCl4
Ti(C,N) 3.0 H2, CH3CN, TiCl4
Al2O3/ZrO2/TiOx 2.6 H2, CO2, AlCl3,
TiCl4, CH4, N2. ZrCl4
Toial thickness 6.8
Here additionally N2 was introduced in the gas phase in a quantity of 20 1. The series of indexable inserts manufactured according to the state-of-the-art technology with an exterior Al2O3 coating as well as a series of indexable inserts with coating as per the invention were used for plain milling of a work piece from a 56NiCrMoV7 material with a strength of 1300 N/mm2 under the following cutting conditions:
Cutting speed vc-3l5m/min
Cutting depth ap - 0.5 mm
Gripping width ae - 67.2 mm
Feed fz = 0.31 mm/tboth
Wear VB = 0.3 mm
The running length for cutting which could be achieved with the cutting inserts as per the state-of-the-art technology amounted to 4000 mm on an average, whereas cutting inserts as per the invention achieved an average running length of 13000 mm. Even here one can see more than a three-fold higher life strength.
Instead of hard metal base bodies, one can also use cermets having known composition. Similarly, for special cases of application, on the ceramic outer layer as per the invention an additional covering layer of ZrCN. HfCN and/or ZrO2, HfO2 or TiN can be applied.
In a further application example, indexable inserts with a coating known as per the state-of-the-art technology and the coating as per the invention were used for milling. The cutting inserts had the geometry RDMW 1605. As substrate body here, similarly one used a hard

metal body with 94 M% WC and 6 M% Co The individual layers known as per the state-of-the-art technology were as follows
Individual layer Thickness (?m) Gases used
TiN 1.5 H2, N2, TiCl4
Ti(C. N) 4 8 H, CH3CN, TiCl4
Al2O3 5 3 H2, CO2, A1Cl4,
Total thickness 116
The coating as per the invention was deposited as follows under the gas phase temperature of 9800C.
Individual layer Thickness (?m) Gases used
TiN , 12 H2. N;, TiCl,
Ti (C. N) 4.8 H2, CH3CN, TiCl4,
Al2O3/Zr02/Ti0, 6.0 H2. CO2, AlCl3,
TiCl4, CH4, HfCl4
Total thickness 12 0
The series of indexable inserts manufactured in a design form known as per the state-of-the-art technology with an outer Al2O3 coating, as well as a series of indexable inserts with a coating as per the invention were used for plain milling of a work piece from a GG25 material (HB = 180 - 240) under the following cutting condition:
Cutting speed vc = 570 m/min
Cutting depth ap = 2.0 mm
Gripping width ae -- 62.5 mm
I-eed fz = 0.20 mm/tooth
Wear VB - 0 .3 mm
The running length per cutting which could be achieved with cutting inserts known from the state-of-the-art technology was on an average 5000 mm, whereas cutting inserts as per the

invention achieved on an average a running length of 15000 mm. Here too one could see a three-fold higher endurance strength.
In a further application example, indexable inserts with a coating known in the state-of-the-art technology and a coating as per the invention were used for milling. The cutting inserts had . the geometry RDMW 1605. As substrate body here, one similarly used a hard metal body with 94 M% WC and 6 M% Co. The individual layers known in the state-of-the-art technology were as follows:
Individual layer Thickness (?m) Gases used
TiN 1.0 H2, N2, TiCl4
Ti (C. N) 4.9 H2, CH3CN, TiCl4
Al2O3 6.3 H2, CO2, AlCl3
Total thickness 12.2
The coating as per the invention was deposited as follows under a gas phase temperature of 980°C:
Individual layer Thickness (?m) Gases used
TiN 1.5 H2, N2, TiCl4
Ti (C, N) 4.1 H2, CH3CN, TiCl4
A12O3/(Zr, Hf) O2/TiOx 7.0 H2, CO2, AlCl3,
TiCl4, CH4, N2, ZrCl4, HfCl4
Total thickness 12.6
The series of indexable inserts manufactured in a design form known from the state-of-the-art technology with an outer Al2O3 coating, as well as the series of indexable inserts with the coating as per the invention were used for plain milling of a work piece of GGG70 material (HB = 250 - 300) under the following cutting condition:

Cutting speed vc - 350 m/min
Cutting depth ap = 2.0 mm
Gripping width ae = 25.0 mm
Feed fz = 0.25 mm/tooth
Wear VB = 0.5 mm
The running length per cutting with the cutting inserts known in the state-of-the-art technology amounted to 1500 mm on an average, whereas cutting inserts as per the invention achieved on an average a running length of 4000 mm.
As long as the compound body is designed as cutting inserts, these are suitable for turning, milling, here particularly high speed milling.

-13-WE CLAIM
Compound material of a coated hard metal or cermet substrate body,
upon which a sole or in the case of a multiple layer coating at least one
layer with a thickness of 0.5 ?m to 25 ?m, preferably the outermost layer,
contains an AI2O3, phase and a phase consisting of ZrO2 and/or HfO2
characterized in that
in the layer containing Al2O3 and a second phase of ZrO2 and/or HfO2
contains a third finely dispersed phase consisting of oxide, oxicarbide,
oxinitride or oxicarbonitride of titanium and of individual crystallites of a
size which is smaller than 1/100 of the crystallite size of the AI2O3 and the
ZrO2 and/or HfO2 phases.
Compound material as claimed in claim 1,
wherein
the third phase consists of TiO2, TiO, Ti2O, Ti2O3, Ti (O, C), Tl (O, N) or Ti
(O, C, N) or mixture phases of these.
Compound material as claimed in claim 1 or 2,
wherein
the portion of the third phase with respect to the total quantity of the layer
should be 0.2 preferably 0.6 to 5 mot%, further preferably at least 1 mol%
and the molecular ratio of the AI2O3-phase with respect to the Zr02-and/or
HfOrphase lies between 9/10 and 10/1, whereby the ZrO2 and/or HfO2 is
present in monoclinical and/or tetragonal form.
Compound material as claimed in claim 1 or 3,
wherein
the third fine crystalline phase consists of individual crystallites having a
size which is smaller than 1/100 of the size of the crystallites of the A12O3-
and the ZrO^-and/or HfO2-phases.
Compound material as claimed in claim 1 or 4,
wherein
The coating is mufti-layered and at least one layer is made of a carbide,
nitride, carbonitrade of one of the elements of the Iva-to Via-group of the
period system.

-14-
Compound material as claimed is claim 5, Where in
there is a layer sequence deposited on the base body made of TiN, Ti (C, N) and an outer layer Al2O3,/ZrO2 and/or HfO2/TiOx with TiOx = TiO2, TiO, Ti2O, TiO3. Ti (O, C). Ti (0. N) or Ti (0, C. N) or mixture phases of these.
Compound material as cleimed one of the claims 1 or 6, Wherein
the thickness of the Al2O3/ZrO2 and/or HfO/TiC3-layer lies between 1 ?m and 10 ?m, preferably between 2 urn and 8 ?m, and/or the entire thickness of the coating should not exceed 25 ?m.
Compound material as claimed in one of the claims 5 to 7.
Wherein
the first layer deposited on the base body has a thickness between 3 ?m and 8 ?m and
the second layer made of Al2O3/ ZrO2 and/or HfO2/TiOx has a thickness between 2 ?m
and 8 ?m, whereby this second layer is cither the outer layer or, on this second layer
an outer layer made of TiN, ZrO2. HfO2, ZrCN or HfCN with a thickness between 1
?m and 5 ?m has been deposited.
Method for production of a layer containing a first phase of A12O3 and a second phase of ZrO2 and/or HfO2, on a substrate body or on a substrate body coated with one or several layers with the help of a CVD- (Chemical Vapour Deposition) method,at deposition temperatures between 900°C and 1000°C in the gas phase, which contains the gases necessary for deposition from the group Al2O3. ZrCl4, HfCl4, CO2, H2, CH4 and N2 or inert gases, and under pressures of 10 to 100000 Pa. in which the gas phase contains 0.2 to 5 mol % of TiCl4.
Method as claimed claim 9.
wherein
the gas phase portion of the AlCl3 is between 1 to 5 mol % and/or the gas phase portion of the ZrCl4 and/or HlCl4 is between 0.2 and 5 mol %.

Method as claimed in 9 or 10, Wherein
the gas phase pressure Title: Compound material and method for its production.
Compound material of a coated hart metal or cermet substrate body, upon which a sole or in the case of a multiple layer coating at least one layer with a thickness of 0.5 ?m to 25 ?m, preferably the outermost layer, contains an Al2O3 phase and a phase consisting of ZrO2 and/or HfO2. Characterized in that in the layer containing Al2O3 and a second phase of ZrO2 and/or HfO2 contains a third finely dispersed phase consisting of oxide, oxicarbide, oxinitride or oxicarbonitride of titanium and of individual crystallites of a size which is smaller than 1/100 of the crystallite size of the Al2O3 and the ZrO2 and /or HfO2 phases.

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Patent Number

201402

Indian Patent Application Number

IN/PCT/2001/00330/KOL

PG Journal Number

6/2007

Publication Date

09-Feb-2007

Grant Date

09-Feb-2007

Date of Filing

22-Mar-2001

Name of Patentee

WIDIA GMBH

Applicant Address

MUNCHENER STRASSE 90, D 45145 ESSEN,

Inventors:

#	Inventor's Name	Inventor's Address
1	WESTPHAL HARTMUT	SCHULSTRASSE 16 D-36466 DERMBACH/RHON,
2	SOTTKE VOLKMAR	HOLZSTRASSE 182 D-45479 MULHEIM,

PCT International Classification Number

C 23 C 30/00,C23 C 1

PCT International Application Number

PCT/DE99/02859

PCT International Filing date

1999-09-04

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	198437439	1998-09-24	Germany