WO1995019941A1

WO1995019941A1 - Wear and corrosion resistant parts for use in liquids and/or solids transportation

Info

Publication number: WO1995019941A1
Application number: PCT/US1995/001025
Authority: WO
Original assignee: Lanxide Technology Company, Lp
Priority date: 1994-01-24
Filing date: 1995-01-24
Publication date: 1995-07-27
Also published as: AU1732895A

Abstract

The invention relates to novel wear and corrosion resistant parts for use in liquids and/or solids transportation and, in a particularly preferred embodiment, the invention relates to slurry pump parts, and methods for making the same. More specifically, the present invention relates to a novel means for joining together at least two parts, and the bodies formed thereby, for use in liquids and/or solids transportation and even more specifically to a novel means for forming a slurry pump suction side liner comprising joining a suction side wear plate to a substrate material or backing plate, which combination of materials may be used in a slurry pump.

Description

DESCRIPTION

WEAR AND CORROSION RESISTANT PARTS FOR USE IN LIQUIDS AND/OR SOLIDS TRANSPORTATION

Technical Field

The invention relates to novel wear and corrosion resistant parts for use in liquids and/or solids transportation, and in a particularly preferred embodiment, the invention relates to slurry pump parts, and methods for making the same. More specifically, the present invention relates to a novel means for joining together at least two parts, and the bodies formed thereby, for use in liquids and/or solids transportation and even more specifically to a novel means for forming a slurry pump suction side liner comprising joining a suction side wear plate to a substrate material or backing plate, which combination of materials may be used in a slurry pump.

Backoround Art Liquid and/or solid transportation systems are subjected to particularly abusive environments, such as corrosive, erosive and the like, environments. In an effort to overcome such harsh environments, engineers have been driven to incorporate, for example, materials with exceptional properties to survive these environments. Particularly preferred materials to withstand these environments include, for example, ceramic, ceramic matrix composites, and/or metal matrix composite materials. Although such materials may be particularly attractive due to certain desirable properties, other complications may arise when attempting to utilize such materials in existing liquid and/or solid transportation systems. For example, joining complexities arise when attempting to incorporate a ceramic, ceramic matrix composite, and/or metal matrix composite material into an existing liquids and/or solids transportation system which may entail bonding or otherwise affixing the ceramic, ceramic matrix composite, and/or metal matrix composite material to, for example, a metal. Particularly, the approach heretofore used has been, for example, to attempt to bond the ceramic, ceramic matrix composite, and/or metal matrix composite to the, for example, metal material by providing a polymer-like material to the interface thereof. Although the bond formed by the polymer-like material may be effective in certain situations, this may not always be true. A particular example of when the polymer-like material bond may not be sufficient, would be in, for example, slurry pump applications. Slurry pumps are used, generally, to transport various fluids and abrasive particles in, for example, the mining industry. As is well known to those in the mining industry, such slurries may be very destructive to the pump parts due to, for example, erosive wear, corrosive wear, etc. Subjected to a particularly abusive environment is a section of the slurry pump referred to as the suction side liner, or the suction side wear plate.

Due to the, for example, erosive and/or corrosive environment, a particularly attractive material for use in this specific application would be, for example, certain ceramic, ceramic matrix composite, or metal matrix composite materials. Even more preferred materials include ceramic, ceramic matrix composites or metal matrix composites formed according to the methods disclosed and claimed in a number of U.S. patents and U.S. patent applications assigned to Lanxide Technology Company, LP. Furthermore, traditional ceramics and/or metal matrix composite materials may also perform in an acceptable manner. Due to the generally high stiffness and brittleness of ceramic and/or ceramic matrix composites and due to the cost of production thereof when compared to simple metal materials, it may be desirable to utilize a relatively small amount of a ceramic and/or ceramic matrix composite suction side liner wear plate in combination with a generally less expensive to manufacture material; for example, metal. The physical combination of a metal backing plate and a ceramic, ceramic matrix composite, and/or metal matrix composite suction side liner wear plate may present certain difficulties which give rise to the present invention.

Description of Commonly Owned U.S. Patents and Patent Applications

A portion of the subject matter of this application is related to that of several Commonly Owned Patents and Commonly Owned and Copending Patent Applications. Particularly, these Patents and Patent Applications describe novel methods for making ceramic matrix composite materials (hereinafter sometimes referred to as "Commonly Owned Ceramic Matrix Patent Applications") and metal matrix composite materials (hereinafter sometimes referred to as "Commonly Owned Metal Matrix Patent(s) and Patent Application(s)").

A novel approach to the formation of ceramic materials is disclosed generically in Commonly Owned U.S. Patent No. 4,713,360, which issued on December 15, 1987 in the names of Marc S. Newkirk et al . and entitled "Novel Ceramic Materials and Methods for Making Same", a European counterpart to which was published in the EPO on September 25, 1985, as Publication No. 0155831. This Patent discloses a method of producing self-supporting ceramic bodies grown as the oxidation reaction product of a molten parent precursor metal which is reacted with a vapor-phase oxidant to form an oxidation reaction product. Molten metal migrates through the formed oxidation reaction product to react with the oxidant thereby continuously developing a ceramic polycrystalline body which can, if desired, include an interconnected metallic component. The process may be enhanced by the use of one or more dopants alloyed with the parent metal. For example, in the case of oxidizing aluminum in air, it is desirable to alloy magnesium and silicon with the aluminum to produce alpha-alumina ceramic structures. This method was improved upon by the application of dopant materials to the surface of the parent metal, as described in Commonly Owned U.S. Patent No. 4,853,352, which issued on August 1, 1989, in the names of Marc S. Newkirk et al., and entitled "Methods of Making Self-Supporting Ceramic Materials", a European counterpart to which was published in the EPO on January 22, 1986, as Publication No. 0 169067.

A novel method for producing a self-supporting ceramic composite by growing an oxidation reaction product from a parent metal into a permeable mass of filler is disclosed in commonly owned and copending U.S. Patent Application Serial No. 07/443,733, filed November 30, 1989, and entitled "Method of Making Composite Articles Having Embedded

Filler", which is a continuation-in-part of commonly owned U.S. Patent Application Serial No. 07/415,180, filed September 29, 1989, now abandoned, which is a divisional of U.S. Patent No. 4,916,113, issued April 10, 1990, and entitled "Methods of Making Ceramic Articles" which is a continuation of U.S. Patent No. 4,851,375, issued July 25, 1989, and entitled "Methods of Making Composite Ceramic Articles Having Embedded Filler", a European counterpart to which was published in the EPO on September 3, 1986, as Publication No. 0 193 292, all in the names of Marc S. Newkirk, et al .

A method for producing ceramic composite bodies having a predetermined geometry or shape is disclosed in Commonly Owned U.S. Patent No. 5,017,526, which issued on May 21, 1991, and entitled

"Method of Making Shaped Ceramic Composite", which is a continuation of U.S. Application Serial No. 06/861,025, filed May 8, 1986 (and now abandoned), a European counterpart to which was published in the EPO on November 11, 1987, as Publication No. 0245 192, both in the names of Marc S. Newkirk et al . In accordance with the method in this U.S. Patent, the developing oxidation reaction product infiltrates a permeable preform of filler material in a direction towards a defined surface boundary. It was discovered that high fidelity is more readily achieved by providing the preform with a barrier means, as disclosed in Commonly Owned and Copending U.S. Patent Application Serial No.

07/819,308, filed January 9, 1992, which is a continuation-in-part of U.S. Patent Application Serial No. 07/786,660, filed November 1, 1991 (now abandoned), which is a continuation-in-part of U.S. Patent Application Serial No. 07/724,236, filed July 1, 1991 (now abandoned), which is a continuation-in-part of Commonly Owned U.S.^* Patent No.

5,236,786, which issued on August 17, 1993, entitled "Shaped Ceramic Composites with a Barrier", which was a continuation of U.S. Patent Application Serial No. 07/295,488, filed January 10, 1989 (now abandoned), which is a continuation of U.S. Patent No. 4,923,832, which issued May 8, 1990, all in the names of Marc S. Newkirk et al., a

European counterpart to which was published in the EPO on November 11, 1987, as Publication No. 0245 193. This method produces shaped self- supporting ceramic bodies, including shaped ceramic composites, by growing the oxidation reaction product of a parent metal to a barrier means spaced from the metal for establishing a boundary or surface. Ceramic composites having a cavity with an interior geometry inversely replicating the shape of a positive mold or pattern are disclosed in Commonly Owned U.S. Patent No. 5,051,382, which issued on September 24, 1991, which is a divisional of U.S. Patent No. 4,828,785, which issued May 9, 1989, both in the names of Marc S. Newkirk, et al . , a European counterpart to which was published in the EPO on September 2, 1987, as Publication No. 0234704 and in U.S. Patent No. 4,859,640, which issued on August 22, 1989, a European counterpart to which was published in the EPO on March 9, 1988, as Publication No. 0259239.

The feeding of additional molten parent metal from a reservoir has been successfully utilized to produce thick ceramic matrix composite structures. Particularly, as disclosed in Commonly Owned U.S. Patent No. 4,918,034, issued April 17, 1990, which is a continuation-in-part of U.S. Patent No. 4,900,699, issued February 13, 1990, both in the names of Marc S. Newkirk et al . , and entitled "Reservoir Feed Method of Making Ceramic Composite Structures and

Structures Made Thereby", a European counterpart to which was published in the EPO on March 30, 1988, as Publication No. 0262075, the reservoir feed method has been successfully applied to form ceramic matrix composite structures. According to the method of this Newkirk et al . invention, the ceramic or ceramic composite body which is produced comprises a self-supporting ceramic composite structure which includes a ceramic matrix obtained by the oxidation reaction of a parent metal with an oxidant to form a polycrystalline material. In conducting the process, a body of the parent metal and a permeable filler are oriented relative to each other so that formation of the oxidation reaction product will occur in a direction toward and into the filler. The parent metal is described as being present as a first source and as a reservoir, the reservoir of metal communicating with the first source due to, for example, gravity flow. The first source of molten parent metal reacts with the oxidant to begin the formation of the oxidation reaction product. As the first source of molten parent metal is consumed, it is replenished, preferably by a continuous means, from the reservoir of parent metal as the oxidation reaction product continues to be produced and infiltrates the filler. Thus, the reservoir assures that sufficient parent metal will be available to continue the process until the oxidation reaction product has grown to a desired extent.

A method for tailoring the constituency of the metallic component of a ceramic matrix composite structure is disclosed in Commonly Owned and Copending U.S. Patent Application Serial No. 07/904,739, filed

June 26, 1992 (now allowed), which was filed as a continuation-in-part of U.S. Application Serial No. 07/793,933, filed November 14, 1991, which issued on February 9, 1993, as U.S. Patent No. 5,185,303, which was filed as a continuation of U.S. Application Serial No. 07/568,618 on August 16, 1990, which issued on November 19, 1991 as U.S. Patent No. 5,066,618, which was filed as a continuation of U.S. Serial No. 07/389,506, filed August 2, 1989, which issued as U.S. Patent No. 5,017,533 on May 21, 1991, which is a continuation of U.S. Patent Application Serial No. 06/908,454, filed September 17, 1986 (now abandoned), a European counterpart to which was published in the EPO on April 6, 1988, as Publication No. 0263051, both of which are in the names of Marc S. Newkirk et al ., and entitled "Method for In Situ

Tailoring the Metallic Component of Ceramic Articles and Articles Made Thereby".

Moreover, U.S. Patent Application Serial No. 07/269,152, filed November 9, 1988, which is a continuation of U.S. Patent Application Serial No. 07/152,518, (which issued as U.S. Patent No. 4,818,734, issued April 4, 1989), in the names of Robert C. Kantner et al., which was a Continuation-in-Part Application of the above-mentioned Serial No. 06/908,454, having the same title and also being Commonly Owned. This Patent and the above-mentioned application 06/908,454, disclose methods for tailoring the constituency of the metallic component (both isolated and interconnected) of ceramic and ceramic matrix composite bodies during formation thereof to impart one or more desirable characteristics to the resulting body. Thus, desired performance characteristics for the ceramic or ceramic composite body are advantageously achieved by incorporating the desired metallic component in situ, rather than from an extrinsic source, or by post-forming techniques.

As discussed in these Commonly Owned Ceramic Matrix Patent Applications and Patents, novel polycrystalline ceramic materials or polycrystalline ceramic composite materials are produced by the oxidation reaction between a parent metal and an oxidant (e.g., a solid, liquid and/or a gas). In accordance with the generic process disclosed in these Commonly Owned Ceramic Matrix Patent Applications and Patents, a parent metal (e.g., aluminum) is heated to an elevated temperature above its melting point but below the melting point of the oxidation reaction product to form a body of molten parent metal which reacts upon contact with an oxidant to form the oxidation reaction product. At this temperature, the oxidation reaction product, or at least a portion thereof, is in contact with and extends between the body of molten parent metal and the oxidant, and molten metal is drawn or transported through the formed oxidation reaction product and towards the oxidant. The transported molten metal forms additional fresh oxidation reaction product upon contact with the oxidant, at the surface of previously formed oxidation reaction product. As the process continues, additional metal is transported through this formation of polycrystalline oxidation reaction product thereby continually "growing" a ceramic structure of interconnected crystallites. The resulting ceramic body may contain metallic constituents, such as non-oxidized constituents of the parent metal, and/or voids. Oxidation is used in its broad sense in all of the Commonly Owned Ceramic Matrix Patent Applications and Patents and in this application, and refers to the loss or sharing of electrons by a metal to an oxidant which may be one or more elements and/or compounds. Accordingly, elements other than oxygen may serve as an oxidant.

In certain cases, the parent metal may require the presence of one or more dopants in order to influence favorably or to facilitate growth of the oxidation reaction product. Such dopants may at least partially alloy with the parent metal at some point during or prior to growth of the oxidation reaction product. For example, in the case of aluminum as the parent-metal and air as the oxidant, dopants such as magnesium and silicon, to name but two of a larger class of dopant materials, can be alloyed with aluminum, and the created growth alloy is utilized as the parent metal. The resulting oxidation reaction product of such a growth alloy, in the case of using oxygen as an oxidant, comprises alumina, typically alpha-alumina.

Novel ceramic composite structures and methods of making the same are also disclosed and claimed in certain of the aforesaid Commonly

Owned Ceramic Matrix Patent Applications and Patents which utilize the oxidation reaction to produce ceramic composite structures comprising a substantially inert filler (note: in some cases it may be desirable to use a reactive filler, e.g., a filler which is at least partially reactive with the advancing oxidation reaction product and/or parent metal) infiltrated by the polycrystalline ceramic matrix. A parent metal is positioned adjacent to a mass of permeable filler (or a preform) which can be shaped and treated to be self-supporting, and is then heated to form a body of molten parent metal which is reacted with an oxidant, as described above, to form an oxidation reaction product. As the oxidation reaction product grows and infiltrates the adjacent filler material, molten parent metal is drawn through previously formed oxidation reaction product within the mass of filler and reacts with the oxidant to form additional fresh oxidation reaction product at the surface of the previously formed oxidation reaction product, as described above. The resulting growth of oxidation reaction product infiltrates or embeds the filler and results in the formation of a ceramic composite structure of a polycrystalline ceramic matrix embedding the filler. As also discussed above, the filler (or preform) may utilize a barrier means to establish a boundary or surface for the ceramic composite structure. Thus, the aforesaid Commonly Owned Ceramic Matrix Patent

Applications and Patents describe the production of oxidation reaction products which are readily grown to desired sizes and thicknesses heretofore believed to be difficult, if not impossible, to achieve with conventional ceramic processing techniques. The production of boride-containing materials has been addressed in commonly owned U.S. Patent No. 5,180,697, which issued January 19, 1993, which was filed as a continuation-in-part of U.S. Patent Application Serial No. 07/446,433, filed December 5, 1989, which issued as U.S. Patent No. 5,017,334 on May 21, 1991, which was filed as a continuation of U.S. Patent Application Serial No. 07/296,771, which issued as U.S. Patent No. 4,885,130 (hereinafter "Patent '130") on December 5, 1989, in the names of Danny R. White, Michael K. Aghajanian and T. Dennis Claar and is entitled "Process for Preparing Self- Supporting Bodies and Products Made Thereby", a European counterpart to which was published in the EPO on July 18, 1990, as Publication No. 0378499.

Briefly summarizing the disclosure of Patent '130, self- supporting ceramic bodies are produced by utilizing a parent metal infiltration and reaction process (i.e., reactive infiltration) in the presence of a mass comprising boron carbide. Particularly, a bed or mass comprising boron carbide and, optionally, one or more of a boron donor material and a carbon donor material is infiltrated by molten parent metal, and the bed may be comprised entirely of boron carbide or only partially of boron carbide, thus resulting in a self-supporting body comprising, at least in part, one or more parent metal boron- containing compounds, which compounds include a parent metal boride or a parent metal boro carbide, or both, and typically also may include a parent metal carbide. It is also disclosed that the mass comprising boron carbide which is to be infiltrated may also contain one or more inert fillers mixed with the boron carbide. Accordingly, by combining an inert filler, the result will be a composite body having a matrix produced by the reactive infiltration of the parent metal, said matrix comprising at least one boron-containing compound, and the matrix may also include a parent metal carbide, the matrix embedding the inert filler. It is further noted that the final composite body product in either of the above-discussed embodiments (i.e., filler or no filler) may include a residual metal as at least one metallic constituent of the original parent metal.

Broadly, in the disclosed method of Patent '130, a mass comprising boron carbide and, optionally, one or more of a boron donor material and a carbon donor material, is placed adjacent to or in contact with a body of molten metal or metal alloy, which is melted in a substantially inert environment within a particular temperature envelope. The molten metal infiltrates the mass comprising boron carbide and reacts with at least the boron carbide to form at least one reaction product. The boron carbide and/or the boron donor material and/or the carbon donor material is reducible, at least in part, by the molten parent metal, thereby forming the parent metal boron-containing compound (e.g., a parent metal boride and/or boro compound under the temperature conditions of the process). Typically, a parent metal carbide is also produced, and in certain cases, a parent metal boro carbide is produced. At least a portion of the reaction product is maintained in contact with the metal, and molten metal is drawn or transported toward the unreacted mass comprising boron carbide by a wieking or a capillary action. This transported metal forms additional parent metal, boride, carbide, and/or boro carbide and the formation or development of a ceramic body is continued until either the parent metal or mass comprising boron carbide has been consumed, or until the reaction temperature is altered to be outside of the reaction temperature envelope. The resulting structure comprises one or more of a parent metal boride, a parent metal boro compound, a parent metal carbide, a metal (which, as discussed in Patent '130, is intended to include alloys and inter etallics), or voids, or any combination thereof. Moreover, these several phases may or may not be interconnected in one or more dimensions throughout the body. The final volume fractions of the boron-containing compounds (i.e., boride and boron compounds), carbon-containing compounds, and metallic phases, and the degree of interconnectivity, can be controlled by changing one or more conditions, such as the initial density of the mass comprising boron carbide, the relative amounts of boron carbide and parent metal, alloys of the parent metal, dilution of the boron carbide with a filler, the amount of boron donor material and/or carbon donor material mixed with the mass comprising boron carbide, temperature, and time. Preferably, conversion of the boron carbide to the parent metal boride, parent metal boro compound(s) and parent metal carbide is at least about 50%, and most preferably at least about 90%.

The typical environment or atmosphere which was utilized in Patent '130 was one which is relatively inert or unreactive under the process conditions. Particularly, it was disclosed that an argon gas, or a vacuum, for example, would be suitable process atmospheres. Still further, it was disclosed that when zirconium was used as the parent metal, the resulting composite comprised zirconium diboride, zirconium carbide, and residual zirconium metal. It was also disclosed that when aluminum parent metal was used with the process, the result was an aluminum boro carbide such as Al36302, A1B₁₂C2 and/or AIB24C4, with aluminum parent metal and other unreacted unoxidized constituents of the parent metal remaining. Other parent metals which were disclosed as being suitable for use with the processing conditions included silicon, titanium, hafnium, lanthanum, iron, calcium, vanadium, niobium, magnesium, and beryllium.

Still further, it is disclosed that by adding a carbon donor material (e.g., graphite powder or carbon black) and/or a boron donor material (e.g., a boron powder, silicon borides, nickel borides and iron borides) to the mass of boron carbide, the ratio or parent metal- boride/parent metal-carbide can be adjusted. For example, if zirconium is used as the parent metal, the ratio of ZrB₂/ZrC can be reduced if a carbon donor material is utilized (i.e., more ZrC is produced out to the addition of a carbon donor material in the mass of boron carbide) while if a boron donor material is utilized, the ratio of Z^/Z c can be increased (i.e., more ZrB is produced due to the addition of a boron donor material in the mass of boron carbide). Still further, the relative size of ZrB2 platelets which are formed in the body may be larger than platelets that are formed by a similar process without the use of a boron donor material. Thus, the addition of a carbon donor material and/or a boron donor material may also effect the morphology of the resultant material.

In another related patent, specifically, U.S. Patent Application No. 4,915,736 (hereinafter referred to as "Patent '736"), issued in the names of Terry Dennis Claar and Gerhard Hans Schiroky, on April 10, 1990, and entitled "A Method of Modifying Ceramic Composite Bodies By a Carburization Process and Articles Made Thereby", a European counterpart to which was published in the EPO on June 28, 1989, as Publication No. 0322346 additional modification techniques are disclosed. Specifically, Patent '736 discloses that a ceramic composite body made in accordance with the teachings of, for example, Patent '130 can be modified by exposing the composite to a gaseous carburizing species. Such a gaseous carburizing species can be produced by, for example, embedding the composite body in a graphitic bedding and reacting at least a portion of the graphitic bedding with moisture or oxygen in a controlled atmosphere furnace. However, the furnace atmosphere should comprise typically, primarily, a non-reactive gas such as argon. It is not clear whether impurities present in the argon gas supply the necessary O2 for forming a carburizing species, or whether the argon gas merely serves as a vehicle which contains impurities generated by some type of volatilization of components in the graphitic bedding or in the composite body. In addition, a gaseous carburizing species could be introduced directly into a controlled atmosphere furnace during heating of the composite body.

Once the gaseous carburizing species has been introduced into the controlled atmosphere furnace, the setup should be designed in such a manner to permit the carburizing species to be able to contact at least a portion of the surface of the composite body buried in the loosely packed graphitic powder. It is believed that carbon in the carburizing species, or carbon from the graphitic bedding, will dissolve into the interconnected zirconium carbide phase, which can then transport the dissolved carbon throughout substantially all of the composite body, if desired, by a vacancy diffusion process. Moreover, Patent '736 discloses that by controlling the time, the exposure of the composite body to the carburizing species and/or the temperature at which the carburization process occurs, a carburized zone or layer can be formed on the surface of the composite body. Such process could result in a hard, wear-resistant surface surrounding a core of composite material having a higher metal content and higher fracture toughness.

Thus, if a composite body was formed having a residual parent metal phase in the amount of between about 5-30 volume percent, such composite body could be modified by a post-carburization treatment to result in from about 0 to about 2 volume percent, typically about 1/2 to about 2 volume percent, of parent metal remaining in the composite body.

Still further, U.S. Patent No. 5,143,870, which issued on September 1, 1992, is a continuation-in-part of U.S. Patent Application Serial No. 07/296,239, filed January 12, 1989, which is a continuation- in-part application of Patent '736, discloses that in addition to a carburizing species, a nitriding and/or boriding species may also be utilized to result in similar modifications to the formed composite bodies.

A novel method of making a metal matrix composite material is disclosed in Commonly Owned U.S. Patent No. 4,828,008, issued May 9, 1989, in the names of White et al., and entitled "Metal Matrix Composites", a European counterpart to which was published in the EPO on November 17, 1988, as Publication No. 0291 441. According to the method of the White et al . invention, a metal matrix composite is produced by infiltrating a permeable mass of filler material (e.g., a ceramic or a ceramic-coated material) with molten aluminum containing at least about 1 percent by weight magnesium, and preferably at least about 3 percent by weight magnesium. Infiltration occurs spontaneously without the application of external pressure or vacuum. A supply of the molten metal alloy is contacted with the mass of filler material at a temperature of at least about 675^βC in the presence of a gas comprising from about 10 to 100 percent, and preferably at least about 50 percent, nitrogen by volume, and a remainder of the gas, if any, being a nonoxidizing gas, e.g., argon. Under these conditions, the molten aluminum alloy infiltrates the ceramic mass under normal atmospheric pressures to form an aluminum (or aluminum alloy) matrix composite. When the desired amount of filler material has been infiltrated with the molten aluminum alloy, the temperature is lowered to solidify the alloy, thereby forming a solid metal matrix structure that embeds the reinforcing filler material. Usually, and preferably, the supply of molten alloy delivered will be sufficient to permit the infiltration to proceed essentially to the boundaries of the mass of filler material. The amount of filler material in the aluminum matrix composites produced according to the White et al . invention may be exceedingly high. In this respect, filler to alloy volumetric ratios of greater than 1:1 may be achieved.

Under the process conditions in the aforesaid White et al . invention, aluminum nitride can form as a discontinuous phase dispersed throughout the aluminum matrix. The amount of nitride in the aluminum matrix may vary depending on such factors as temperature, alloy composition, gas composition and filler material. Thus, by controlling one or more such factors in the system, it is possible to tailor certain properties of the composite. For some end use applications, however, it may be desirable that the composite contain little or substantially no aluminum nitride.

It has been observed that higher temperatures favor infiltration but render the process more conducive to nitride formation. The White et al . invention allows the choice of a balance between infiltration kinetics and nitride formation.

An example of suitable barrier means for use with metal matrix composite formation is described in Commonly Owned U.S. Patent No. 4,935,055, issued June 19, 1990, in the names of Michael K. Aghajanian et al., and entitled "Method of Making Metal Matrix Composite with the Use of a Barrier", a European counterpart to which was published in the EPO on July 12, 1989, as Publication No. 0323 945. According to the method of this Aghajanian et al . invention, a barrier means (e.g., particulate titanium diboride or a graphite material such as a flexible graphite tape product sold by Union Carbide under the trade name GRAFOIL^®) is disposed on a defined surface boundary of a filler material and matrix alloy infiltrates up to the boundary defined by the barrier means. The barrier means is used to inhibit, prevent, or terminate infiltration of the molten alloy, thereby providing net, or near net, shapes in the resultant metal matrix composite. Accordingly, the formed metal matrix composite bodies have an outer shape which substantially corresponds to the inner shape of the barrier means. The method of U.S. Patent No. 4,828,008, was improved upon by Commonly Owned and Copending U.S. Patent Application Serial No. 07/994,064, filed December 18, 1992 (now allowed), which is a continuation of U.S. Patent Application Serial No. 07/759,745, filed September 12, 1991 (now abandoned), which is a continuation of U.S. Patent Application Serial No. 07/517,541, filed April 24, 1990 (now abandoned), which is a continuation of U.S. Patent Application Serial No. 07/168,284, filed March 15, 1988 (and now abandoned), both in the names of Michael K. Aghajanian and Marc S. Newkirk and entitled "Metal Matrix Composites and Techniques for Making the Same", a European counterpart to which was published in the EPO on September 20, 1989, as Publication No. 0333692. In accordance with the methods disclosed in this U.S. Patent Application, a matrix metal alloy is present as a first source of metal and as a reservoir of matrix metal alloy which communicates with the first source of molten metal due to, for example, gravity flow. Particularly, under the conditions described in this patent application, the first source of molten matrix alloy begins to infiltrate the mass of filler material under normal atmospheric pressures and thus begins the formation of a metal matrix composite. The first source of molten matrix metal alloy is consumed during its infiltration into the mass of filler material and, if desired, can be replenished, preferably by a continuous means, from the reservoir of molten matrix metal as the spontaneous infiltration continues. When a desired amount of permeable filler has been spontaneously infiltrated by the molten matrix alloy, the temperature is lowered to solidify the alloy, thereby forming a solid metal matrix structure that embeds the reinforcing filler material. It should be understood that the use of a reservoir of metal is simply one embodiment of the invention described in this patent application and it is not necessary to combine the reservoir embodiment with each of the alternate embodiments of the invention disclosed therein, some of which could also be beneficial to use in combination with the present invention. The reservoir of metal can be present in an amount such that it provides for a sufficient amount of metal to infiltrate the permeable mass of filler material to a predetermined extent. Alternatively, an optional barrier means can contact the permeable mass of filler on at least one side thereof to define a surface boundary.

Moreover, while the supply of molten matrix alloy delivered should be at least sufficient to permit spontaneous infiltration to proceed essentially to the boundaries (e.g., barriers) of the permeable mass of filler material, the amount of alloy present in the reservoir could exceed such sufficient amount so that not only will there be a sufficient amount of alloy for complete infiltration, but excess molten metal alloy could remain and be attached to the metal matrix composite body. Thus, when excess molten alloy is present, the resulting body will be a complex composite body (e.g., a macrocomposite), wherein an infiltrated ceramic body having a metal matrix therein will be directly bonded to excess metal remaining in the reservoir.

Further improvements in metal matrix technology can be found in Commonly Owned U.S. Patent No. 5,249,621, issued October 5, 1993, and entitled "A Method of Forming Metal Matrix Composite Bodies by a Spontaneous Infiltration Process, and Products Produced Therefrom," which is a continuation of U.S. Application Serial No. 07/521,043, filed May 9, 1990 (now abandoned), which is a continuation-in-part of U.S. Patent Application Serial No. 07/484,753, filed February 23, 1990 (now abandoned), which is a continuation-in-part of U.S. Patent Application Serial No. 07/432,661, filed November 7, 1989 (now abandoned), which is a continuation-in-part of U.S. Patent Application Serial No. 07/416,327, filed October 6, 1989 (now abandoned), a European counterpart to which was published in the EPO on June 27, 1990, as Publication No. 0375588, in the names of Aghajanian, et al . and entitled "A Method of Forming Metal Matrix Composite Bodies by a Spontaneous Infiltration Process, and Products Produced Therefrom". According to this Aghajanian, et al . invention, spontaneous infiltration of a matrix metal into a permeable mass of filler material or preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the filler material or preform. Aghajanian, et al. disclose a number of matrix metal/infiltration enhancer precursor/infiltrating atmosphere systems which exhibit spontaneous infiltration. Specifically, Aghajanian, et al. disclose that spontaneous infiltration behavior has been observed in the aluminum/magnesium/nitrogen system; the aluminum/strontium/- nitrogen system; the aluminum/zinc/oxygen system; and the aluminum/- calcium/nitrogen system. However, it is clear from the disclosure set forth in the Aghajanian, et al. invention that the spontaneous infiltration behavior should occur in other matrix metal/infiltration enhancer precursor/infiltrating atmosphere systems.

A novel method of forming a metal matrix composite by infiltration of a permeable mass of filler contained in a ceramic matrix composite mold is disclosed in Commonly Owned U.S. Patent No. 4,871,008, issued October 3, 1989, which issued from U.S. Patent Application Serial No. 07/142,385, filed January 11, 1988, by Dwivedi et al., both entitled "Method of Making Metal Matrix Composites", a European counterpart to which was published in the EPO on July 19, 1989, as Publication No. 0324706. According to the method of the Dwivedi et al . invention, a mold is formed by the directed oxidation of a molten precursor metal or parent metal with an oxidant to develop or grow a polycrystalline oxidation reaction product which embeds at least a portion of a preform comprised of a suitable filler (referred to as a "first filler"). The formed mold of ceramic matrix composite is then provided with a second filler and the second filler and mold are contacted with molten metal, and the mold contents are hermetically sealed, most typically by introducing at least one molten metal into the entry or opening which seals the mold. The hermetically sealed bedding may contain entrapped air, but the entrapped air and the mold contents are isolated or sealed so as to exclude or shut-out the external or ambient air. By providing a hermetic environment, effective infiltration of the second filler at moderate molten metal temperatures is achieved, and therefore obviates or eliminates any necessity for wetting agents, special alloying ingredients in the molten matrix metal, applied mechanical pressure, applied vacuum, special gas atmospheres or other infiltration expedients.

The above-discussed commonly owned patent describes a method for the production of a metal matrix composite body, which may be bonded to a ceramic matrix composite body, and the novel bodies which are produced therefrom. A method of forming metal matrix composite bodies by a self- generated vacuum process is disclosed in Commonly Owned U.S. Patent No. 5,224,533, issued July 6, 1993, which is a continuation of U.S. Application Serial No. 07/381,523, filed July 18, 1989 (now abandoned), in the names of Robert C. antner et al., and entitled "A Method of Forming Metal Matrix Composite Bodies by a Self-Generated Vacuum Process and Products Produced Therefrom", a European counterpart to which was published in the EPO on January 23, 1991, as Publication No. 0409763 A2. These patent applications disclose a method whereby a molten matrix metal is contacted with a filler material or a preform in the presence of a reactive atmosphere, and, at least at some point during the process, the molten matrix metal reacts, either partially or substantially completely, with the reactive atmosphere, thereby causing the molten matrix metal to infiltrate the filler material or preform due to, at least in part, the creation of a self-generated vacuum.

Such self-generated vacuum infiltration occurs without the application of any external pressure or vacuum.

A method for forming polymer matrix composite bodies is disclosed in commonly owned and copending U.S. Application Serial No. 07/932,903, filed August 20, 1992 (now abandoned), which is a continuation of U.S. Application Serial No. 07/690,134, filed April 23, 1991 (now abandoned), in the names of Christopher M. Looby et al . , and entitled "Polymer Matrix Composite Bodies and Methods For Making the Same", a foreign counterpart to which was published on October 29, 1992, as International Publication No. WO 92/18327. These patent applications disclose a method whereby an appropriate filler material is caused to be placed within a particular polymer material, whereby the polymer material functions as a matrix and the filler material synergistically interacts with the polymer to form a novel polymer matrix composite body. Moreover, the application discloses that by combining specific polymer matrix materials with specific filler or reinforcing materials, very desirable wear parts can be fabricated.

The entire disclosures of all of the foregoing commonly owned patent applications and Patents are expressly incorporated herein by reference. Summary of the Invention

This invention relates generally to novel parts for use in liquids and/or solids transportation systems. More particularly, this invention relates to a novel means for joining at least two materials together which materials will be used in a liquids and/or solids transportation system. The invention relates to a broad range of parts for use in liquids and/or solids transportation systems; however, a better understanding of the broad nature of the present invention would readily be understood by reference to a particularly preferred embodiment. This particularly preferred embodiment is a novel suction side liner for use in slurry pumps. Although the application hereinafter is directed to a specific discussion of suction side liners for use in slurry pumps, this discussion is for convenience only and should not be construed as limiting the present invention to this specific embodiment.

This invention relates generally to novel suction side liners for use in slurry pumps. It has been discovered that utilization of a preferred first material, such as, a ceramic, ceramic matrix composite and/or metal matrix composite material in combination with a second material which functions as a support substrate or backing plate material results in an attractive combination of materials for use in slurry pumps. A particularly novel concept of the present invention is the manner in which the first ceramic, ceramic matrix composite, and/or metal matrix composite wear plate is joined to the substrate material or backing plate.

Generally, a suction side wear plate is first manufactured from any suitable ceramic, ceramic matrix composite, and/or metal matrix composite material; and, more preferably, a ceramic, ceramic matrix composite, and/or metal matrix composite formed according to any one of the methods set forth in the Commonly Owned U.S. Patents and Patent Applications discussed above. Next, a backing plate made of, for example, metal (e.g., an iron or steel product) is manufactured to an appropriate size. However, each of the backing plate and the suction side wear plate are manufactured so as to have at least one joining means for aiding in the coupling of the backing plate to the suction side wear plate. For example, the backing plate may have machined therethrough at least one hole which is capable of accepting at least one insert, screw, bolt, pin or the like, and the corresponding section of the suction side wear plate is manufactured so as to have at least one means for accepting at least a portion of the, for example, insert or screw. Before placing the wear plate and backing plate in contact, a polymer-like or epoxy material is spread substantially evenly on at least a portion of one or both of the surfaces to be joined together. When the backing plate is butted against the suction wear plate, the at least one joining means of each piece can be aligned and the, for example, insert, screw, bolt, pin, or the like, may then be inserted and the gap remaining in the suction wear plate and the backing plate may then be filled with a suitable polymer-like material; or the polymer-like material may first be placed in the at least one joining means and then the, for example, insert, screw, bolt, or the like, may then be placed into the polymer-like material and the polymer-like material may be then permitted to cure. Thus, resulting in a novel means for bonding or joining the suction wear plate to the substrate or backing plate.

The novel combination of the polymer-like material; the inserts, screws, bolts, or the like; the holes in the backing plate; the channel or circular cavities in the wear plate; and the polymer-like material or epoxy placed on either or both surfaces of the parts to be joined, results in a sufficiently strong bond between the backing plate and the suction wear plate so as to allow for the parts to withstand the harsh environment experienced within the slurry pump. The harsh environment within the slurry pump may include heat which, without the presence of the above materials, could possibly cause just a polymer-like material bond to fail due to the presence of the heat. That is, a sufficiently high temperature may cause the polymer-like material to lose its ability to bond two or more surfaces together. By combining the materials as set forth above, the bond is sufficiently strong to withstand this harsh environment.

Brief Description of the Drawings

Figure la is a schematic cross-sectional view of a suction side liner comprising a suction wear plate attached to a metal backing plate according to the present invention. Figure lb is a schematic cross-sectional view of the joining means utilized in accordance with the present invention.

Figure lc is a plan view of Figure la.

Figure 2a is a schematic cross-sectional view of a suction side liner comprising a suction wear plate attached to a metal backing plate according to the present invention.

Figure 2b is a schematic cross-sectional view of the joining means utilized in accordance with the present invention.

Figure 2c is a plan view of Figure 2a. Figure 3 is a schematic cross-sectional view of the lay-up used to form the ceramic matrix composite wear plate according to Example 1.

Figure 4 is a schematic cross-sectional view of the preform formed in Example 1.

Figure 5 is a schematic of the process of applying a barrier material to the preform formed in accordance with Example 1.

Figure 6 is a schematic cross-sectional view of the metal backing plate used in accordance with Example 1.

Figure 7a is a plan view of the preform having an undercut circular channel formed in accordance with Example 1. Figure 7b is a schematic cross-sectional view of the preform having an undercut circular channel formed in accordance with Example 1.

Detailed Description of the Invention and Preferred Embodiments This invention relates generally to novel parts for use in liquids and/or solids transportation systems. More particularly, this invention relates to a novel means for joining at least two materials together which materials will be used in a liquids and/or solids transportation system. The invention relates to a broad range of parts for use in liquids and/or solids transportation systems; however, a better understanding of the broad nature of the present invention would readily be understood by reference to a particularly preferred embodiment. This particularly preferred embodiment is a novel suction side liner for use in slurry pumps. Although the application hereinafter is directed to a specific discussion of suction side liners for use in slurry pumps, this discussion is for convenience only and should not be construed as limiting the present invention to this specific embodiment.

Generally, a suction side wear plate is first manufactured from any suitable ceramic, ceramic matrix composite, and/or metal matrix composite material; and, more preferably, a ceramic, ceramic matrix composite, and/or metal matrix composite formed according to any one of the methods set forth in the Commonly Owned U.S. Patents and Patent Applications discussed above. Next, a backing plate made of, for example, metal (e.g., an iron or steel product) is manufactured to an appropriate size. However, each of the backing plate and the suction side wear plate are manufactured so as to have at least one joining means for aiding in the coupling of the backing plate to the suction side wear plate. For example, the backing plate may have machined therein at least one hole which is capable of accepting at least one insert, screw, bolt, pin, or the like, and the corresponding section of the suction side wear plate is manufactured so as to have at least one means for accepting at least a portion of the, for example, insert, screw, bolt, or the like. Before placing the wear plate and backing plate in contact, a polymer-like material is spread substantially evenly on at least a portion of one or both of the surfaces to be joined together. When the backing plate is butted against the suction wear plate, the at least one joining means of each piece can be aligned and the, for example, insert, screw, bolt, pin, or the like, may then be inserted and the gap remaining in the suction wear plate and the backing plate may then be filled with a suitable polymer-like material; or the polymer-like material may first be placed in the at least one joining means and then the, for example, insert, screw, bolt, or the like, may then be placed into the polymer-like material and the polymer-like material may be then permitted to cure. Thus, resulting in a novel means for bonding or joining the suction wear plate to the substrate or backing plate. A more thorough understanding of the present invention may be had with particular reference to certain preferred embodiments which are set forth in the figures.

Figures la, lb, and lc show a particularly preferred embodiment comprising a suction side wear plate 1, a backing plate 2, and the novel means for joining the suction side wear plate 1 and the backing plate 2. Specifically, Figure lb shows in detail the means for connecting the suction side wear plate 1 to the backing plate 2. As can be seen in Figure lb, a means for accepting a insert, screw, bolt, or the like, is formed in the suction side wear plate and is designated by the numeral 6. It should be noted that, in this particular embodiment, the portion of the cavity 6 closest to the surface of the wear plate 1 which will be in contact with the backing plate 2 has a smaller measurement than the portion of the cavity 6 which is further from the backing plate 2. That is, the cavity 6 is somewhat undercut to result in an additional mechanical means for adjoining the suction side wear plate 1 to the backing plate 2. It should be noted that a channel could be formed which is not undercut. That is, the channel could also have substantially the same width through its entire length and depth. Such a channel has also been found to be satisfactory. Furthermore, the backing plate 2 has therein at least one hole 7 which is capable of accepting an element 4 such as an insert, screw, bolt, or the like. Furthermore, it should be noted that the at least one cavity 6 in the suction side wear plate 1 may comprise a single circular channel extending radially around the entire length of the suction side wear plate 1.

After forming a suction side wear plate and a backing plate as described above, one, or both, of the surfaces of the two parts may then be provided with a thin layer of, for example, an epoxy or polymer-like material utilizing, for example, a trowel. After applying the epoxy or polymer-like material to one or both sides of the suction side wear plate and the backing plate, the parts may then be placed together and aligned so that the at least one hole(s) in the backing plate is aligned with the cavity(ies) in the suction side wear plate. Next, the cavity in the suction side wear plate may be substantially completely filled with a polymer-like material and, while still in its uncured state, at least one insert, screw, bolt, or the like, may then be placed into the at least one hole in the backing plate and seated in the polymer filled cavity(ies) of the suction side wear plate. Furthermore, the at least one hole in the backing plate may also be filled with the polymer-like material. Moreover, when a screw or bolt is utilized, at least one washer 5 may be used in combination with the screw or bolt. After seating the insert, screw, bolt, or the like, the polymer-like material contained in the cavity(ies) of the suction side wear plate and, optionally, the at least one hole in the backing plate, is allowed to cure as is the epoxy or polymer-like material spread over the surface of one or both of the suction side wear plate and backing plate. After the polymer-like material and/or epoxy is substantially completely cured, the novel part is ready for use in an appropriate slurry pump.

With reference to Figures 2a, 2b, and 2c, another preferred embodiment is depicted. Specifically, rather than utilizing the "undercut" channel or cavity set forth in Figures la, lb, and lc, at least one circular cavity 6 may be formed in the suction side wear plate 1. The at least one circular cavity 6 formed in the suction side wear plate can have a diameter somewhat greater than the corresponding hole 7 formed in the backing plate 2; however, the at least one circular cavity 6 in the suction side wear plate 1 does not need to be formed through the entire thickness of the suction side wear plate 1. After forming the at least one circular cavity 6 in the suction side wear plate 1 and.the corresponding number of holes 7 in the backing plate 2, an epoxy or polymer-like material may be spread substantially uniformly over at least one surface of either part (or both parts) and the parts may then be placed together and the holes 7 lined up concentrically with the cavity(ies) 6. Thereafter, the circular cavity(ies) 6 in the suction side wear plate 1 may be filled with a suitable polymer-like material and, optionally, the hole(s) 7 in the backing plate 2 may also be filled with the suitable polymer-like material, and before the polymer-like material cures, an insert, screw, bolt, or the like, may be placed into each hole 7 and into the polymer- like material. Furthermore, when a screw or bolt is utilized, at least one washer 5 may be used in combination therewith.

After the polymer-like material in the at least one circular cavity 6 in the suction side wear plate 1 and/or the at least one hole 7 in the backing plate 2 has cured and the epoxy or polymer-like material spread on at least one side of either or both of the suction side wear plate 1 and/or backing plate 2 has cured substantially completely, the assembly is ready for use in a suitable slurry pump. Additionally, it should be noted that rather than using a polymer-like material, it may be desirable to pour a, for example, molten metal into either the channel or circular cavities contained in the suction side wear plate and/or the holes contained in the backing plate and then allow the molten metal to solidify and obtain a sufficiently strong bond as well. Furthermore, as an additional preferred embodiment, either, or both, the backing plate or the suction side wear plate may be provided with fine grooves on the surface to be joined with the other part to aid in the epoxy or polymer-like material bonding to the two materials. As still a further embodiment, the suction side wear plate need not be a monolithic part. Specifically, the suction side wear plate may comprise a number of smaller parts that, when assembled, take the form of a single suction side wear plate.

The novel combination of the polymer-like material; the inserts, screws, bolts, or the like; the holes in the backing plate; the channel or circular cavities in the wear plate; and the polymer-like material or epoxy placed on either or both surfaces of the parts to be joined, results in a sufficiently strong bond between the backing plate and the suction wear plate so as to allow for the parts to withstand the harsh environment experienced within a typical slurry pump. The harsh environment within the slurry pump may include heat which, without the presence of the above materials, could possibly cause just a polymer¬ like material bond to fail due to the presence of such heat. That is, a sufficiently high temperature may cause the polymer-like material to lose its ability to bond two or more surfaces together. By combining the materials as set forth in the present invention, the bond is sufficiently strong to withstand the environment. Various demonstrations of the present invention are included in the Example immediately following. However, this Example should be considered as being illustrative and should not be construed as limiting the scope of the invention as defined in the appended claims.

Example 1

The present Example demonstrates, among other things, a method for forming a suction side liner by first forming a ceramic matrix composite body in the form of a suction side wear plate and then joining the suction side wear plate to a metal substrate or backing plate.

About 14 kilograms of a sediment casting mixture comprising nominally about 55 weight percent of about 90 grit green silicon carbide (Exolon, Tonawanda, NY), about 24 weight percent of about 220 grit green silicon carbide (Exolon, Tonawanda, NY), about 0.1 weight percent Colloids 581-B defoamer (Colloids, Inc., Newark, NJ), about 17 weight percent deionized water, about 2.3 weight percent Nyacol colloidal silica (Nyacol Products, Ashland, MA) and about 1.6 weight percent Elmer's^® professional polyvinyl acetate glue (Borden Company, Columbus, OH) was prepared. Specifically, the defoamer, the Elmer's^® professional polyvinyl acetate glue and deionized water were combined in a stainless steel bowl and hand mixed until a homogeneous solution was formed. Subsequently, the 90 grit green silicon carbide and the 220 grit green silicon carbide were combined with the liquids. This combination was then mixed by hand to eliminate any agglomeration of materials while assuring that the silicon carbide filler material was fully wetted. The mixing was completed after about 10 minutes thereby forming a sediment castable filler material mixture.

A rubber mold was then formed to achieve a cavity which replicated the shape of the suction wear plate depicted in Figure 4. Specifically, the inner diameter measured about 8 1/3 inches (212 mm), the outer diameter at the bottom portion measured about 22 1/4 inches (565 mm), the outer diameter at the top portion measured about 227/10 inches (577 mm), the thickness at the outer diameter measured about 0.875 inch (22 mm) and the thickness at the inner diameter measured about 1 9/10 inches (48 mm). The rubber mold was then placed onto a Centron Model VR5D1 vibration table (FMC Corporation, West Reading, PA). After the oscillator to the vibrating table was turned on, the intensity setting for the oscillator was adjusted to a level such that the rubber mold would vibrate without moving along the surface of the table. Quantities of the sediment castable filler material mixture were then placed into the cavity of the rubber mold to fill the mold. To assure a substantially even distribution and aid in the de-airing of the castable filler material mixture, a polyethylene rod having a diameter of about 0.5 inches (13 mm) and a length of about 2 feet (610 mm) was placed into the cavity of the rubber mold and contacted with the castable slurry material. The steps were repeated until the cavity of the rubber mold was substantially completely filled. Then the vibrating table and the substantially filled mold were allowed to vibrate for about 1 hour. During this time, the solids in the castable filler material mixture settled thereby producing surface water at the top of the mold. The water was removed from the mold using a combination of a pipet and a sponge. Once the water had been removed, the rubber mold and its contents were allowed to sit in air at about room temperature for about an hour while the vibrating table remained on. The rubber mold and its contents were then placed into a freezer set at about -15^βF (-20^βC) approximately at the center of the freezer. After about 24 hours, the mold and its contents were removed from the freezer and the now frozen preform was removed from the rubber mold. Next, a circular channel 20 was undercut into the frozen preform as depicted in Figures 7a and 7b. Specifically, the circular channel was undercut to a thickness of about 1/4 inch (6 mm), an inner diameter of about 143/4 inches (375 mm) and an outer diameter of about 17 1/4 inches (438 mm) at the bottom of the channel, and an inner diameter of about 14.89 inches (378 mm) and an outer diameter of about 17.11 inches (435 mm) at the top of the channel.

The frozen preform was then placed onto a loose bed of about 14 grit green silicon carbide particulate supported by an about 0.25 inch (6.5 mm) rubber plate. The preform was stabilized to prevent it from rolling, thereby forming a drying setup. A temperature of about 160"F (7TC), was established in a convection oven (Blue M, Blue Island, IL), and the drying setup was placed in the oven for about 14 hours. Upon removal from the oven, any 14 grit green silicon carbide which had adhered to the outer surfaces of the hollow cylinder was removed, thereby preparing the preform for growth initiation and barrier coating.

A barrier material mixture comprising about 60 weight percent of about -325 mesh Nyad SP wollastonite (purchased from East Tech, Philadelphia, PA), about 34 weight percent commercially available isopropyl alcohol, and about 6 weight percent of a solution comprising about 5 weight percent klucel "L" (E. I. du Pont de Nemours and Company, Inc., Wilmington, DE) and the balance ethyl alcohol was prepared. Specifically, the 5 weight percent klucel "L" ethyl alcohol solution was prepared by combining about 100 grams of klucel "L" with about 1900 grams of commercially available ethyl alcohol. After the klucel "L" ethyl alcohol solution was prepared, the -325 mesh wollastonite, the commercially available isopropyl alcohol, the 5 percent klucel "L" ethyl alcohol solution and about 1.8 kilograms of 1/4 inch (6.5 mm) diameter alumina mixing media were combined in a one gallon Nalgene^® plastic jar. The jar was closed and sealed and.then placed on a jar mill for about 45 minutes. The jar and its contents were then removed from the jar mill and the contents were poured through a colander to separate the 1/4 inch (6.5 mm) diameter alumina mixing media from the barrier mixture.

The preform was then prepared for barrier coating. Specifically, as depicted in Figure 5, the preform 10 was placed with the channel side facing down onto a turn table 12 which was covered with brown paper 11. The reservoir chamber 13 of a Binks spray gun having a devil-bise JGV-560 nozzle (Binks, Franklin Park, IL) was filled with the barrier material mixture. Compressed air supply running through hose 14 was set at about 20 pounds per square inch (1.046 kilograms per centimeter squared). The barrier material spray 15 from the spray gun was inclined at about a 45° angle with the preform 10 as the turn table 12 was rotated thereby applying a substantially uniform coating to the inner diameter, outer diameter and side of the preform. In about 15 minutes the barrier material coating had dried.

A growth initiator mixture comprising about 18 weight percent 5% by weight klucel "L" ethanol solution, about 1.3 weight percent Bentone inorganic thixotropic agent, about 30.7 weight percent isopropyl alcohol, and about 50 weight percent of about 200 grit silicon metal powder. After the ingredients for the growth initiator mixture were placed in a plastic jar and the jar was sealed, the jar and its contents were mixed by vigorously hand shaking the jar. The growth initiator mixture was then placed into a reservoir jar of a model 62-2 Pasche airbrush. The preform was replaced on the turn table with the channel side facing up. Supports were used to stabilize the preform. The growth initiation mixture material was then spray coated on the surface of the preform containing the channel and into the channel to a thickness of at least 0.04 inches. After allowing the growth initiation mixture material to dry for about 30 minutes, the preform was ready for incorporation into a growth lay-up.

The growth lay-up is depicted in Figure 3. Specifically, a refractory boat 30 made from Castolast 3000 refractory mix (New Castle Refractories, New Castle, PA) and supported by a steel shell was obtained. About 2 inches (51 mm) of Nyad SP coarse wollastonite 31 (East Tech, Philadelphia, PA) was poured into the bottom of the refractory boat 30 and leveled to make a layer of about 2 inches in the bottom of the refractory boat 30. A ring shaped matrix metal ingot 32 comprising by weight about 14.5% Si, 3.5% Cu, 3.0% Zn, 0.25% Mg, 0.90% Fe, and the balance Al and having an inner diameter of about 81/3 inches (212 mm) and an outer diameter of about 22 7/10 inches (577 mm) and weighing about 32 kilograms was placed into the refractory boat 30 and onto the layer of Nyad SP coarse wollastonite 31. The preform 33 was then concentrically placed onto the ring shaped matrix metal ingot 32 with the surface having the initiator mixture applied thereto in contact with the matrix metal. Coarse wollastonite was then poured into the hole contained in the preform 33 and matrix metal 32 and around the preform 33 to a level approximately equal to the top of the preform 33 thereby completing the formation of the growth lay-up. The growth lay-up and its contents were then placed into an air atmosphere resistance heated furnace which was fitted with a stainless steel tube for supplying a gaseous source of 0₂ into the furnace. The stainless steel tube was connected to a gaseous source of O2 and an O2 gas flow rate of about 15 cubic centimeters per hour was established through the furnace. The furnace and its contents were then heated from about room temperature to about 560^βC at a rate of about 70^βC per hour; held at about 560^βC, for about 10 minutes; raised from about 560^βC to about 910"C at a rate of about 200'C; held at about 910^βC for about 220 hours; and then cooled from about 910°C to about 850°C at a rate of about 100'C per hour. The now formed ceramic matrix composite suction wear plate was then removed from the furnace. The surface of the ceramic matrix composite suction wear plate to be in contact with the metal backing plate was prepared by placing the ceramic composite on a 60 inch (152.4 cm) diameter turntable within a Wheelabrator grit blaster (Model #WMT60, The Wheelbrator Corporation, Shenandoah, GA) with the surface that had been in contact with the matrix metal facing up. The top, side, and channel of the ceramic composite were subjected to grit blasting (utilizing GL25 steel grinding media obtained from The Wheelabrator Corporation) for a time sufficient to remove substantially any remaining matrix metal from the ceramic composite body. Next, the surface to be placed into contact with the backing plate was lightly sandblasted to remove any debris and loose pieces. The suction wear plate was then placed under a hood and the surface to be placed in contact with the metal backing plate was thoroughly cleaned with commercially available acetone (however, any commercially available non-oil based solvent could be used) utilizing clean paper towels.

A cast iron backing plate, as depicted in Figure 6, having an inner diameter of about 9 inches (229 mm), an outer diameter of about 227/10 inches (577 mm) on the side to be contacted with the ceramic matrix composite wear plate, an outer diameter about 23 1/3 inches (593 mm) on the side to face away from the ceramic matrix composite wear plate, a thickness of about 1 1/10 inches (28 mm), a cylindrical collar about 7 inches (178 mm) high at its inner diameter facing away from the ceramic matrix composite wear plate, and eight holes 40 drilled therethrough. The eight holes each had a diameter of about 1 inch (25.4 mm), with counterbores of about 1 3/4 inch (44 mm) being about 0.145 inch (406 mm) deep. The holes were evenly spaced apart in a circular manner, with the center of each hole being approximately 16 inches from the center of the plate. The surface of the metal backing plate to be contacted with the suction wear plate was prepared by lightly sandblasting the entire surface to remove any debris and loose pieces and, additionally, was thoroughly cleaned with commercially available acetone (however, any commercially available non-oil based solvent could be used) utilizing clean paper towels. After the acetone had evaporated from both pieces, about 100 parts by weight CGL 1310 resin (Ciba-Giegy, East Lansing, MI) was mixed with about 8 parts by weight RP510 hardener (Ciba-Giegy, East Lansing, MI) according to the manufacturer's directions, and, utilizing a trowel, having an about 1/16 inch (1.6 mm) notch, a thin coating of the polymer material was applied to substantially the entire surface of the metal backing plate and the suction wear plate which were to be in contact with one another. With the ceramic matrix composite suction wear plate sufficiently supported and with the surface to be contacted with the metal backing plate facing up, the metal backing plate was carefully lifted and the surface having the polymer layer was placed into contact with the surface of the suction wear plate having the polymer layer. The metal backing plate was then rotated at least about 180° and the holes in the metal backing plate were aligned with the channel in the suction wear plate.

Next, the polymer material was poured into each of the holes in the metal backing plate such that both the channel in the suction wear plate and the holes in the metal backing plate were filled substantially completely with the polymer material. After filling the channel and holes substantially completely with the polymer material, 8 hexagonal zinc bolts measuring about 4 inches (102 mm) in length and about 5/8 inch (16 mm) in diameter and having washers placed against the bolt heads were placed into the 8 holes in the metal backing plate such that the bolt heads contacted the bottom portion of the channel in the ceramic matrix composite wear plate. The polymer materials were then allowed to cure completely. Next, a washer was placed over the protruding part of each bolt and then locknuts were tightened down on each bolt. After tightening each bolt, the protruding portion of each bolt was cut off to produce a flush surface on the metal backing plate. Figures la, lb, and lc depict in schematic form the formed body.

Claims

Cl aims

1. A macrocomposite body comprising: a wear resistant material having a first side and a second side and at least one means for accepting at least one element; a backing material having a first side and a second side and at least one means for accepting at least one element; said first side of said wear resistant material being in contact with said first side of said backing material, wherein said at least one means for accepting at least one element in said wear material is aligned with said at least one means for accepting at least one element in said backing material to form at least one cavity; at least one bonding material disposed in at least a portion of said cavity; and wherein said at least one element is positioned at least partially into said at least one cavity.

2. The macrocomposite body of claim 1, wherein said wear resistant material comprises a material selected from the group consisting of a ceramic, a ceramic matrix composite, and a metal matrix composite material.

3. The macrocomposite of claim 2, wherein said backing material comprises a metal .

4. The macrocomposite of claim 1, wherein said at least one bonding material comprises a material selected from the group consisting of a polymer and a metal.

5. The macrocomposite of claim 2, wherein said at least one bonding material comprises a material selected from the group consisting of a polymer and a metal.

6. The macrocomposite of claim 3, wherein said at least one bonding material comprises a material selected from the group consisting of a polymer and a metal.

7. The macrocomposite of claim 1, wherein said at least one element comprises a material selected from the group consisting of screws, bolts, pins, and inserts.

8. The macrocomposite of claim 1, wherein a polymer material is provided to at least a portion of the interface between said first side of said wear resistant material and said first side of said backing material, in addition to said at least one bonding material.

9. A suction side liner comprising: a wear resistant suction side wear plate disc having a first side, a second side, at least one means for accepting at least one element, and a hollow center; a backing plate disc having a first side^', a second side, at least one means for accepting at least one element, and a hollow center; said first side of said wear resistant suction side wear plate disc being in contact with said first side of said backing plate disc, wherein said at least one means for accepting at least one element in said wear plate disc is aligned with said at least one means for accepting at least one element in said backing plate disc to form at least one cavity; at least one bonding material disposed in at least a portion of said cavity; and wherein said at least one element is placed at least partially into said at least one cavity.

10. The suction side liner of claim 9, wherein said suction side wear plate disc comprises a material selected from the group consisting of a ceramic, a ceramic matrix composite, and a metal matrix composite.

11. The suction side liner of claim 9, wherein said backing plate disc comprises a metal.

12. The suction side liner of claim 9, wherein said at least one bonding material comprises a material selected from the group consisting of a polymer and a metal.

13. The suction side liner of claim 9, wherein said at least one element comprises a material selected from the group consisting of screws, bolts, pins, and inserts.

14. The suction side liner of claim 9, wherein a polymer material is provided to at least a portion of the interface between said first side of said suction side wear plate disc and said first side of said backing plate disc, in addition to said at least one bonding material .

15. The suction side liner of claim 9, wherein said at least one means for accepting at least one element in said suction side wear plate disc comprises at least one circular cavity, and wherein said at least one means for accepting at least one element in said backing plate disc comprises at least one hole.

16. The suction side liner of claim 9, wherein said at least one means for accepting at least one element in said suction side wear plate disc comprises a circular channel, and wherein said at least one means for accepting at least one element in said backing plate disc comprises at least one hole.

17. The suction side liner of claim 15, wherein said at least one element comprises at least one bolt having a first end with a head and a second threaded end, a washer, and a nut.

18. The suction side liner of claim 17, wherein said bolt is positioned with its head substantially in contact with the bottom of said circular cavity, wherein a washer is in contact with said bolt head, and wherein a nut and washer are disposed on said threaded end.

19. The suction side liner of claim 16, wherein said at least one element comprises at least one bolt having a first end with a head and a second threaded end, washer, and nut.

20. The suction side of claim 19, wherein said bolt is positioned with its head substantially in contact with the bottom of said circular cavity, wherein a washer is in contact with said bolt head, and wherein a nut and washer are disposed on said threaded end.