US20170241007A1

US20170241007A1 - Component with Composite Coating for Enhanced Wear Resistance and Method for Making Same

Info

Publication number: US20170241007A1
Application number: US15/047,158
Authority: US
Inventors: Daniel Sordelet
Original assignee: Caterpillar Inc
Current assignee: Caterpillar Inc
Priority date: 2016-02-18
Filing date: 2016-02-18
Publication date: 2017-08-24

Abstract

A component includes a body and a wear layer. The body has a substrate surface. The wear layer is applied to the body such that the wear layer is in overlying relationship with at least a portion of the substrate surface. The wear layer is thermal-spray bonded to the body. The wear layer comprises a composite of a steel alloy and a copper alloy.

Description

TECHNICAL FIELD

This patent disclosure relates generally to components and, more particularly, to components and methods for making the same with a composite coating with enhanced wear resistance.

BACKGROUND

When two surfaces are in contact under conditions of loading and relative motion, one or both contacting surface can be subjected to wear damage. For example, if loading is high while relative motion between the two surfaces is relatively low (e.g., as experienced by an oscillating pin joint), then galling (i.e., metal-to-metal welding or strong adhesion) can occur and lead to significant surface damage. Conversely, at higher relative motions (e.g., as experienced by a connecting rod bearing) and particularly in poorly-lubricated conditions, then the possibility for one contacting surface to be worn preferentially exists. Different contact surface techniques have been developed to resist the deleterious forms of surface damage.
For example, U.S. Pat. No. 7,438,979 is entitled, “Thermal Spray Membrane Contact Material, Contact Member and Contact Part, and Apparatuses to Which They Are Applied.” The '979 patent is directed to a thermal spray membrane contact material for use in a bucket connecting apparatus connecting an arm and a bucket by a work implement connecting pin. The connecting pin comprises a base material made of steel having an axis function and a contact surface formed of a thermal spray membrane contact material film-formed on the base material, said contact surface being placed at least on a supported surface site of the work implement connecting pin relative to a bracket and on a slipping contact surface with a work implement bushing. The thermal spray membrane contact material is composed of a Mo metal phase, or 10 vol % or more of a Mo metal phase and a metal phase and/or alloy phase containing one or more elements selected from the group consisting of Fe, Ni, Co, Cr, Cu and Zn.
There is a continued need in the art to provide additional solutions to enhance the wear resistance of components that can be subjected to wear damage. For example, many applications are highly cost sensitive. As such, there is a continued need to provide a wear-resistant coating solution that uses readily-available, lower-cost materials that can be processed with economical equipment to improve the durability and usefulness of a component.
It will be appreciated that this background description has been created by the inventor to aid the reader, and is not to be taken as an indication that any of the indicated problems were themselves appreciated in the art. While the described principles can, in some aspects and embodiments, alleviate the problems inherent in other systems, it will be appreciated that the scope of the protected innovation is defined by the attached claims, and not by the ability of any disclosed feature to solve any specific problem noted herein.

SUMMARY

In embodiments, the present disclosure describes a component. The component includes a body and a wear layer. The body has a substrate surface. The wear layer is applied to the body such that the wear layer is in overlying relationship with at least a portion of the substrate surface. The wear layer is thermal-spray bonded to the body. The wear layer comprises a composite of a steel alloy and a copper alloy.
In another embodiment, a method of making a component is described. The component includes a body having a substrate surface. A wear layer is applied, via thermal spray coating, upon the body such that the wear layer is in overlying relationship with at least a portion of the substrate surface. The wear layer comprises a composite of a steel alloy and a copper alloy. The wear layer is allowed to solidify such that the wear layer is bonded to the body.
Further and alternative aspects and features of the disclosed principles will be appreciated from the following detailed description and the accompanying drawings. As will be appreciated, the components and methods of making a component disclosed herein are capable of being carried out in other and different embodiments, and capable of being modified in various respects. Accordingly, it is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and do not restrict the scope of the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of a component constructed in accordance with principles of the present disclosure.

FIG. 2 is a longitudinal cross-sectional view of the component of FIG. 1.

FIG. 3 is a diagrammatic view of an embodiment of a thermal spray machine in the form of a twin wire arc thermal spray machine suitable for use in embodiments of a method of making a component following principles of the present disclosure.

FIG. 4 is a flowchart illustrating steps of an embodiment of a method of making a component following principles of the present disclosure.

FIG. 5 are graphs of load (lb·f) versus time (seconds), speed (rpm) versus time (seconds), and coefficient of friction versus time (seconds) for a block-on-ring test of a specimen of a control test block having a wear layer made from a composite of naval brass and molybdenum which was applied using a twin wire arc thermal spray process using one naval brass thermal spray wire and one molybdenum thermal spray wire.

FIG. 6 are graphs of load (lb·f) versus time (seconds), speed (rpm) versus time (seconds), and coefficient of friction versus time (seconds) for a block-on-ring test, as in FIG. 5, of a specimen of an exemplary block made according to principles of the present disclosure having a wear layer made from a composite of naval brass and SAE 1080 steel which was applied using a twin wire arc thermal spray process as used for the control specimen of FIG. 5, but using one naval brass thermal spray wire and one SAE 1080 steel thermal spray wire.

FIG. 7 are graphs of load (lb·f) versus time (seconds), speed (rpm) versus time (seconds), and coefficient of friction versus time (seconds) for a block-on-ring test, as in FIG. 5, of a specimen of another exemplary block made according to principles of the present disclosure having a wear layer made from a composite of naval brass and SAE 304 stainless steel which was applied using a twin wire arc thermal spray process as used for the control specimen of FIG. 5, but using one naval brass thermal spray wire and one SAE 304 stainless steel thermal spray wire.

FIG. 8 are graphs of load (lb·f) versus time (seconds), speed (rpm) versus time (seconds), and coefficient of friction versus time (seconds) for a block-on-ring test, as in FIG. 5, of a specimen of yet another exemplary block made according to principles of the present disclosure having a wear layer made from a composite of naval brass and SAE 316 stainless steel which was applied using a twin wire arc thermal spray process as used for the control specimen of FIG. 5, but using one naval brass thermal spray wire and one SAE 316 stainless steel thermal spray wire.

It should be understood that the drawings are not necessarily to scale and that the disclosed embodiments are sometimes illustrated diagrammatically and in partial views. In certain instances, details which are not necessary for an understanding of this disclosure or which render other details difficult to perceive may have been omitted. It should be understood, of course, that this disclosure is not limited to the particular embodiments illustrated herein.

DETAILED DESCRIPTION

Embodiments of components having a wear layer and methods of making the same are disclosed herein. In embodiments, a method of making a component following principles of the present disclosure can be used to apply a wear layer, via thermal spray coating, upon a body of the component such that the wear layer is in overlying relationship with at least a portion of a substrate surface of the body. In embodiments, the wear layer comprises a composite of a steel alloy and a copper alloy.
Turning now to the Figures, there is shown in FIGS. 1 and 2 an exemplary embodiment of a component 50 constructed according to principles of the present disclosure. The component 50 can be made using an embodiment of a method following principles of the present disclosure for applying a wear layer 52 to a substrate surface 54 of a body 55 of the component 50.
The component 50 of FIG. 1 is shown in the form of a sleeve bearing. In embodiments, the component 50 can be configured for use in a final drive assembly of a ground-engaging member (e.g., a wheel) of a machine, such as an off-highway truck, for example. In one such arrangement, the component 50 is part of a final drive of a planetary system for use in a machine, such as, a wheel loader, for example. The sleeve bearing 50 can be inserted over a pin as part of a pin joint in the final drive.
It should be understood that, in other embodiments, the component 50 can have different forms. For example, in embodiments, the component 50 can be in the form of a bearing pin, a thrust bearing, a roller, a seal member, etc. In another arrangement of a final drive assembly, the component 50, constructed according to principles of the present disclosure, can be in the form of a pin and the substrate surface 54 can comprise an exterior surface of the pin. The wear layer 52 can be applied to the body 55 of the pin via a suitable thermal spray process. In this arrangement, the sleeve bearing can be omitted.
The component 50 includes the body 55 and the wear layer 52. In the illustrated embodiment, the body 55 comprises a hollow cylinder. In embodiments, the body 55 of the component 50 can be made from any suitable material, such as a metal alloy, for example. In embodiments, the body 55 is made from cast bronze or wrought bronze.
In embodiments, the substrate surface 54 of the body 55 can be treated to facilitate the application of the wear layer 52 thereto. For example, in embodiments, the substrate surface 54 can be subjected to grit blasting, using any suitable technique as will be appreciated by one skilled in the art, to help promote the adhesion of the wear layer 52 to the body 55.
In embodiments, the wear layer 52 is applied to the body 55 such that the wear layer 52 is in overlying relationship with at least a portion of the substrate surface 54. In the illustrated embodiment, the wear layer 52 substantially covers the substrate surface 54 which is in the form of an exterior cylindrical sidewall surface of the body 55.
In some embodiments, a bond layer can be interposed between the wear layer 52 and the substrate surface 54 of the body 55; in such embodiments, the wear layer 52 is still considered to be in overlying relationship with the substrate surface 54 disposed under the wear layer 52. In at least some of such embodiments, the bond layer can have a material composition that is different from the wear layer 52 and/or the body 55.
In the illustrated embodiment, the substrate surface 54 comprises an exterior cylindrical sidewall surface of the body 55. In other embodiments, the substrate surface 54 can comprise an interior surface of the body 55. In embodiments, the wear layer 52 is applied to an exterior and/or an internal sidewall surface of the sleeve bearing body 55 using a suitable thermal spray process. For example, in embodiments, the wear layer 52 can be applied to the body 55 using a suitable thermal spray process, such as a twin wire arc process. In the illustrated embodiment, the wear layer 52 is thermal-spray bonded to the substrate surface 54 of the body 55.
The wear layer 52 comprises a composite of a steel alloy and a copper alloy. In embodiments, the composite from which the wear layer 52 is made consists essentially of the steel alloy and the copper alloy. In embodiments, the composite from which the wear layer 52 is made contains molybdenum in an amount no greater than ten percent by weight (10 wt %) of the total weight of the composite, and, in yet other embodiments, no greater than five percent by weight (5 wt %) of the total weight of the composite. In embodiments, the steel alloy of the composite from which the wear layer 52 is made is substantially free of molybdenum (excluding trace amounts in the steel alloy). In embodiments, the composite from which the wear layer 52 is made is substantially free of molybdenum (excluding trace amounts in the steel alloy and/or copper alloy of the composite).
In embodiments where the wear layer 52 is applied using a wire arc spray coating technique, the steel alloy can be supplied as a coil of wire that is configured to be fed through a thermal spray machine. In embodiments, the steel alloy of the composite from which the wear layer 52 is made comprises at least one of a carbon steel alloy and a stainless steel alloy.
In embodiments, the steel alloy of the composite from which the wear layer 52 is made is a carbon steel alloy comprising a mild steel alloy containing 0.05 wt %-0.25 wt % carbon. In embodiments, the steel alloy of the composite from which the wear layer 52 is made is a carbon steel alloy comprising a SAE 1080 steel alloy according to the SAE International/American Iron and Steel Institute (AISI) numbering system. In embodiments, the SAE 1080 steel used in the composite from which the wear layer 52 is made has a chemical composition as follows in Table I:

TABLE I

Chemical Composition

Element/Compound

	Fe	C	Mn	S	P

Weight (%)	98.1-98.7	0.75-0.88	0.6-0.9	Up to 0.05	Up to 0.04

In embodiments, the steel alloy of the composite from which the wear layer 52 is made is a stainless steel alloy comprising an austenitic stainless steel alloy. In embodiments, the austenitic stainless steel alloy used in the composite contains a maximum of 0.15 wt % carbon, a minimum of 16 wt % chromium, and a sufficient amount of nickel and/or manganese to retain an austenitic structure over a temperature range between the cryogenic region to the melting point of the alloy.
In embodiments, the steel alloy of the composite is a stainless steel alloy comprising a SAE 300-series austenitic stainless steel alloy. For example, in embodiments, the wear layer 52 is made from a composite having a SAE 304 stainless steel that nominally includes 18 wt % chromium and 8 wt % nickel. In embodiments, the SAE 304 stainless steel used in the composite from which the wear layer 52 is made has a chemical composition as follows in Table II:

TABLE II

Chemical Composition

	Element/Compound	Weight (%)

	Carbon	Up to 0.08
	Manganese	Up to 2.0
	Phosphorus	Up to 0.045
	Sulfur	Up to 0.03
	Silicon	Up to 0.75
	Chromium	18.0-20.0
	Nickel	8.0-12.0
	Nitrogen	Up to 0.1
	Iron	Balance

In embodiments, the wear layer 52 is made from a composite having a SAE 316 stainless steel, also referred to as a marine-grade stainless steel. In embodiments, the SAE 316 stainless steel used in the composite nominally includes 17 wt % chromium and 12 wt % nickel. In embodiments, the SAE 316 stainless steel used in the composite from which the wear layer 52 is made has a chemical composition as follows in Table III:

TABLE III

Chemical Composition

	Element/Compound	Weight (%)

	Carbon	Up to 0.08
	Manganese	Up to 2.0
	Phosphorus	Up to 0.045
	Sulfur	Up to 0.03
	Silicon	Up to 0.75
	Chromium	16.0-18.0
	Nickel	10.0-14.0
	Molybdenum	2.0-3.0
	Nitrogen	Up to 0.1
	Iron	Balance

In embodiments where the wear layer 52 is applied using a wire arc spray coating technique, the copper alloy can be supplied as a coil of wire that is configured to be fed through a thermal spray machine. In embodiments, the copper alloy of the composite from which the wear layer 52 is made comprises at least one of a copper-zinc alloy and an aluminum-bronze alloy.
In embodiments, the copper alloy of the composite from which the wear layer 52 is made comprises a copper-zinc alloy referred to as naval brass, which nominally contain forty percent by weight zinc and sixty percent by weight copper, but can include other elements including iron, tin, manganese, and silicon, for example. In embodiments, the copper alloy of the composite from which the wear layer 52 is made comprises a copper-zinc alloy referred to as cartridge brass, which nominally contain thirty percent by weight zinc and seventy percent by weight copper, but can include other elements including iron, tin, manganese, and silicon, for example. For example, in embodiments, the copper alloy of the composite from which the wear layer 52 is made comprises a naval brass that nominally includes 60 wt % copper, 0.75 wt % tin, and 39.2 wt % zinc.
In embodiments, the copper alloy can be in the form of a commercially-available thermal spray wire (e.g., 12T wire from Praxair/TAFA) for use in a suitable wire arc thermal spray machine. In at least some of such embodiments, the copper alloy is in the form of a copper-zinc alloy thermal spray wire comprising naval brass having the following chemical composition in Table IV:

TABLE IV

Chemical Composition

Element/Compound

	Zn	Cu	Fe	Sn	Mn	Si

Weight (%)	39.50	58.62	0.76	0.92	0.08	0.13

In embodiments, the copper alloy of the composite from which the wear layer 52 is made comprises an aluminum bronze which is a type of bronze in which aluminum is the main alloying metal added to copper, in contrast to standard bronze (copper and tin) or brass (copper and zinc). In embodiments, the aluminum bronze used in the composite from which the wear layer 52 is made nominally includes 5 wt % to 11 wt % aluminum and the balance being copper, but can include other elements such as iron, nickel, manganese, lead, zinc, and silicon.
In embodiments, an aluminum bronze thermal spray wire can also be used with a steel alloy wire to apply the wear layer 52 using a twin wire arc thermal spray process. In one arrangement the aluminum bronze wire is a commercially-available thermal spray wire (e.g., 10T from Praxair/TAFA) and has the following chemical composition in Table V:

TABLE V

Chemical Composition

		Total
	Element/Compound	Others

	Cu						(Including
	(Balance)	Al	Mn	Pb	Zn	Si	Iron)

Weight (%)	92.85	6.90	0.02	0.02	0.17	0.03	0.01

In embodiments, the composite from which the wear layer 52 is made has a volume. The volume of the wear layer 52 is made up by a first volume fraction of the steel alloy and a second volume fraction of the copper alloy. In embodiments, the first volume fraction of the steel alloy is at least five percent of the volume of the composite. In embodiments, the first volume fraction of the steel alloy is in a range between ten percent and fifty percent of the volume of the composite. In still other embodiments, the first volume fraction of the steel alloy is in a range between twenty-five percent and fifty percent of the volume of the composite.
In the illustrated embodiment, the first volume fraction of the steel alloy and the second volume fraction of the copper alloy are substantially equal to each other. In the illustrated embodiment, the wear layer 52 is thermal-spray bonded to the substrate surface 54 of the body 55 of the component 50 using a twin wire arc spray process in which the steel alloy and the copper alloy are in the form of separate thermal spray wires having substantially the same diameter and being fed through the wire arc thermal spray machine at substantially the same feed rate. Accordingly, the wire arc thermal spray machine sprayed a composite made up of the steel alloy and the copper alloy such that the wear layer 52 applied to the body 55 of the component 50 has a volume that is substantially made of equal volumetric halves of the steel alloy and the copper alloy.
In embodiments, the wear layer 52 can be applied to the body 55 of the component 50 using any suitable thermal spraying technique, such as one selected from the group including, an atmospheric plasma spray process, a combustion wire process, a combustion powder process, an electric arc wire spray process, a high velocity oxy-fuel (HVOF) coating spray process, and the like, as known to one of ordinary skill in the art. For example, in embodiments, a twin wire arc thermal spray process can be used to apply the wear layer 52 to the body 55 of the component 50.
Referring to FIG. 3, an embodiment of a wire arc thermal spray machine 70 is shown. The wire arc thermal spray machine 70 can be used to carry out a method for applying the wear layer 52, comprising a composite according to principles of the present disclosure, to the substrate surface 54 of the body 55 of the component 50. In embodiments, the wire arc thermal spray machine 70 can be used to make the component 50 as any of an original manufacture, a repair, and/or a remanufacture of the component 50.
The wire arc thermal spray machine 70 illustrated in FIG. 3 includes a first spool 72 of a first thermal spray wire 73, a second spool 74 of a second thermal spray wire 75, a power supply unit 77, a control switch 78, a first feed mechanism 79, a second feed mechanism 80, a spray torch 82, and a supply of pressurized gas 84.
Each of the first thermal spray wire 73 and the second thermal spray wire 75 are in electrical connection with the power supply unit 77 such that the first and second thermal spray wires 73, 75 can be selectively supplied with an opposing electrical polarity via operation of the control switch 78. The first and second feed mechanisms 79, 80 are configured to selectively feed the first and second thermal spray wires 73, 75 to the spray torch 82 at a controlled, matched feed rate. The control switch 78 can be configured to selectively operate the first and second feed mechanism 79, 80.
The spray torch 82 includes a first wire passage 88, a second wire passage 89, and a central gas passage 90. The first wire passage 88 and the second wire passage 89 are respectively configured to receive the first thermal spray wire 73 and the second thermal spray wire 75 therethrough and to route those wires continuously such that respective distal ends 92, 93 of the first and second thermal spray wires 73, 75 define an arc gap 95 therebetween that is substantially aligned with an outlet 97 of the central gas passage 90. The central gas passage 90 is pneumatically connected to the supply of pressurized gas 84. The supply of pressurized gas 84 can be configured to selectively propel a flow of compressed gas 99 through the central gas passage 90 out the outlet 97 to the arc gap 95.
In embodiments, the supply of pressurized gas 84 can comprise any suitable gas for thermal spraying as will be appreciated by one of ordinary skill in the art. For example, in embodiments, the supply of pressurized gas 84 can comprise air or nitrogen as the propelling gas for the wire arc process.
The wire arc thermal spray machine 70 can be used in a twin wire arc thermal spray process in which the wire arc thermal spray machine 70 draws the first and second thermal spray wires 73, 75 from the first and second spools 72, 74, respectively, and feeds those wires through the spray torch 82 at a controlled, matched feed rate. An operator can activate the wire arc thermal spray machine 70 via actuation of the control switch 78 to supply high electric voltage with opposing charges via the power supply unit 77 between the first thermal spray wire 73 and the second thermal spray wire 75 at the arc gap 95. The first and second feed mechanisms 79, 80 respectively feed the first and second thermal spray wires 73, 75 into close proximity with each other. An electric arc is discharged therebetween across the arc gap 95 defined at the respective distal ends 92, 93 of the first and second thermal spray wires 73, 75 that creates sufficient heat to continuously melt the respective distal ends 92, 93 of the first and second thermal spray wires 73, 75. The flow of compressed gas 99 propels a composite of atomized molten or semi-molten material 101 from the first and second thermal spray wires 73, 75 onto the substrate surface 54 of the body 55 of the component 50. The applied molten particles rapidly solidify on the substrate surface 54 to form a coating of the wear layer 52.
In embodiments, the first thermal spray wire 73 and the second thermal spray wire 75 can be made from different materials. For example, in embodiments, the first thermal spray wire 73 can comprise a steel alloy and the second thermal spray wire 75 can comprise a copper alloy such that the wire arc thermal spray machine 70 applies a composite of the first and second thermal spray wires 73, 75 upon the substrate surface 54 of the body 55 to form the wear layer 52. Accordingly, as the first thermal spray wire 73 and the second thermal spray wire 75 are made up of a steel alloy and a copper alloy, respectively, the wear layer 52 is made from a composite that has the same volumetric relationship as found in and between the first and second thermal spray wires 73, 75.
In embodiments, the composite of the steel alloy and the copper alloy in the form of the first thermal spray wire 73 and the second thermal spray wire 75, respectively, that is applied by the wire arc thermal spray machine 70 to the substrate surface 54 of the body 55 to form the wear layer 52 can be any suitable combination of a copper alloy and a steel alloy as described above. For example, in embodiments, the first thermal spray wire 73 can be made from a SAE 1080 steel, and the second thermal spray wire can be made form a naval brass. In other embodiments, the first thermal spray wire 73 can be made from a SAE 300-series austenitic stainless steel alloy (e.g., SAE 304 or SAE 316), and the second thermal spray wire can be made form a naval brass. In embodiments, the particular wire types selected for the first and second thermal spray wires 73, 75 can be determined according to the substrate material and the intended use of the component in question.
In embodiments, the first and second thermal spray wires 73, 75 can have substantially the same cross-sectional area and be fed by the wire arc thermal spray machine 70 at substantially the same feed rate such that the volume of the composite that forms the wear layer 52 includes a first volume fraction of the steel alloy and a second volume fraction of the copper alloy that are substantially equal to each other. In embodiments, the size and/or feed rate of one of the first and second thermal spray wires 73, 75 can be varied to change the relationship between the first volume fraction and the second volume fraction of the wear layer 52.
In yet other embodiments, one or more of the first and second thermal spray wires 73, 75 can comprise a cored wire. For example, in embodiments, at least one of the first and second thermal spray wires 73, 75 comprises a cored wire for use in a twin wire arc thermal spray process that is made by providing a sheet of copper alloy material and rolling it to form a cylinder. The copper alloy cylinder is filled with a powder filling of a steel alloy, and the cylinder seam can be crimped closed to form the thermal spray wire. In such manner, the relative amount of the copper alloy and the steel alloy in the composite used to form the wear layer 52 can be varied. In embodiments, the first and second thermal spray wires 73, 75 comprise cored wires having the same chemical composition. In other embodiments, the first and second thermal spray wires 73, 75 comprise two cored wires having different chemical compositions to provide a spectrum of possible composites for the wear layer 52.
In embodiments, the wear layer 52 is made from a composite that is different from the base material of the body 55 of the component 50. In embodiments of such cases, the composite from which the wear layer 52 is made is compatible with the base material of the body 55 of the component 50 at the substrate surface 54 such that the wear layer 52 applied to the substrate surface 54 bonds with the substrate surface 54 of the component 50 after undergoing a thermal spray process. In embodiments of such cases, the composite from which the wear layer 52 is made can have at least one enhanced material property relative to the base material of the substrate surface 54 of the body 55 of the component 50, such as, wear resistance, fatigue strength, and the like.
Although the illustrated embodiment depicts the component 50 in the form of a sleeve bearing, this is only exemplary. It will be apparent to one skilled in the art that various aspects of the disclosed principles relating to the thermal spraying of components can be used with a variety of different types of components. Accordingly, one skilled in the art will understand that, in other embodiments, a method of making a component following principles of the present disclosure can be used to manufacture, repair, or remanufacture different types of components.
In embodiments, any suitable thermal spray machine can be used to carry out a method of making a component in accordance with principles of the present disclosure to manufacture, repair, and/or remanufacture the component 50. In embodiments, a method of making a component following principles of the present disclosure can be used to make, repair, or remanufacture any embodiment of a component according to principles discussed herein.
Referring to FIG. 4, steps of an embodiment of a method 400 of making a component following principles of the present disclosure are shown. In the method 400 of making, the component includes a body having a substrate surface. A wear layer is applied, via thermal spray coating, upon the body such that the wear layer is in overlying relationship with at least a portion of the substrate surface (step 410). The wear layer comprises a composite of a steel alloy and a copper alloy.
The wear layer is allowed to solidify such that the wear layer is bonded to the body (step 420). In embodiments, the wear layer can be subjected to machining to bring the component within a target range for a specification value for the exterior surface of the component, including the wear layer.
In embodiments, the composite can comprise any of the composite combinations following principles discussed herein. For example, in embodiments, the steel alloy comprises at least one of a carbon steel alloy and an austenitic stainless steel alloy, and the copper alloy comprises at least one of a copper-zinc alloy and an aluminum-bronze alloy. In still other embodiments, the steel alloy comprises at least one of a SAE 1080 steel and a SAE 300-series austenitic stainless steel alloy (e.g., SAE 304 or SAE 316), and the copper alloy comprises a naval brass.
In embodiments, any suitable thermal spray coating technique can be used. In embodiments, thermal spray coating includes using a twin wire arc thermal spray machine.
In embodiments, the component is manufactured from a suitable material, such as a metal alloy. In embodiments, the body is made at least in part from a substrate material, and the steel alloy and the copper alloy of the composite are both different from the substrate material. For example, in embodiments, the wear layer can be made from a composite such that the wear layer is harder than the base material used to manufacture the body of the component. The wear layer can be disposed over a coverage area of the substrate surface of the body that is oriented over a wear path associated with the intended use of the component.
In embodiments of a method following principles of the present disclosure, the method can also include machining the body to form the substrate surface in a remanufacturing operation. The component can be one that has been removed from service in a machine system and has been machined to form the substrate surface to remove material of the body of the component having a defect therein.
For example, in embodiments, a component in the form of a used shaft (e.g., a pin) can be machined (such as on a lathe) to remove damaged and/or worn material therefrom. The substrate surface can have a dimension with a value that is less than a specification value. The step of applying the wear layer to the body upon the body (step 410) includes depositing the wear layer such that the value of the dimension when the wear layer is included therein is increased to be equal to or greater than the specification value. In embodiments, the wear layer can be subjected to machining (e.g., grinding) to bring the value of the dimension within a target range for the specification value. In embodiments, a conventional or a CNC lathe machine, a milling machine, and the like can be used for a machining operation. In other embodiments, machining operations can be performed using other techniques, such as, grinding, electrical discharge machining, electrochemical machining, electron beam machining, photochemical machining, and ultrasonic machining, for example.

INDUSTRIAL APPLICABILITY

The industrial applicability of the embodiments of a component and a method of making a component described herein will be readily appreciated from the foregoing discussion. The described principles are applicable to a variety of components. For example, components such as those used in a final drive assembly of a ground-engaging member (e.g., a wheel) of a machine can be subjected to relatively harsh conditions while in service resulting in various forms of wear and/or damage to the component. Using principles of the present disclosure, a wear layer of a composite according to principles of the present disclosure that is harder than the base material from which the body of the component is made can be applied to the surface of the component to increase the service time of the component. Using principles of the present disclosure, a component can also be rebuilt or re-coated with a wear layer made from a composite including a steel alloy and a copper alloy according to principles of the present disclosure in a method of making according to the present disclosure to further increase the service time of the component.
In embodiments, a component constructed in accordance with principles of the present disclosure includes a wear layer made from a composite of a steel alloy and a copper alloy that provides enhanced resistance to corrosion, erosion, and/or wear relative to a base material from which a body of the component is made. Advantageously, in embodiments, the steel alloy of the composite from which the wear layer is made has a cost that is less than that for a comparable amount of molybdenum.
Surprisingly and unexpectedly, a component constructed according to principles of the present disclosure having a wear layer made from a composite formulated according to principles of the present disclosure can provide similar galling resistance compared to a wear layer made form a composite using the same copper alloy but replacing the steel alloy with molybdenum. Test data for a wear layer made from a composite of molybdenum and naval brass is shown in FIG. 5. Test data for a wear layer made from a composite of SAE 1080 steel and naval brass according to principles of the present disclosure is shown in FIG. 6. Test data for a wear layer made from a composite of SAE 304 stainless steel and naval brass according to principles of the present disclosure is shown in FIG. 7. Test data for a wear layer made from a composite of SAE 316 stainless steel and naval brass according to principles of the present disclosure is shown in FIG. 8.
In each instance, a component, which includes a body in the form of a block and a wear layer applied thereto using a twin wire arc process, was made under similar conditions, but in which one of the thermal spray wires was changed as noted. Namely, the molybdenum wire was replaced with a steel alloy according to principles of the present disclosure. Each component was subjected to a block-on-ring test in which the component (block) was placed into contact with a ring (made from No Cr-4140 steel) that was rotated relative to the block at 100 rpm and in which the block was subjected to step loading over time in 25 lb·f increments from 50 lb·f to 1275 lb·f, as shown in the test results.
Referring to FIGS. 5 and 6, a wear layer according to principles of the present disclosure, which was made from a composite of individual steel and brass particles formed from a SAE 1080 steel thermal spray wire and a naval brass (Cu-40Zn) thermal spray wire in a twin wire arc process, demonstrated comparable galling resistance to a wear layer made under similar conditions but replacing the SAE 1080 steel thermal spray wire with a molybdenum thermal spray wire (at least 99 wt % Mo). In addition, under the tested conditions, the wear layer according to principles of the present disclosure which was made from SAE 1080 steel and naval brass exhibited reduced friction compared to the wear layer made from molybdenum and naval brass.
Referring to FIGS. 7 and 8, a wear layer according to principles of the present disclosure, which was made from a composite of individual steel and brass particles formed from one of a SAE 300-series stainless steel thermal spray wire and a naval brass (Cu-40Zn) thermal spray wire in a twin wire arc process, demonstrated acceptable galling resistance when compared to the wear layer of molybdenum and naval brass of FIG. 5. In addition, the wear layers according to principles of the present disclosure made from stainless steel in FIGS. 7 and 8 provide enhanced corrosion resistance.
It will be appreciated that the foregoing description provides examples of the disclosed system and technique. However, it is contemplated that other implementations of the disclosure may differ in detail from the foregoing examples. All references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for the features of interest, but not to exclude such from the scope of the disclosure entirely unless otherwise specifically indicated.
Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims

What is claimed is:

1. A component comprising:

a body, the body having a substrate surface; and

a wear layer, the wear layer applied to the body such that the wear layer is in overlying relationship with at least a portion of the substrate surface, the wear layer being thermal-spray bonded to the body, and the wear layer comprising a composite of a steel alloy and a copper alloy.

2. The component according to claim 1, wherein the composite includes a volume, the volume including a first volume fraction of the steel alloy and a second volume fraction of the copper alloy, and wherein the first volume fraction is at least five percent of the volume of the composite.

3. The component according to claim 1, wherein the composite includes a volume, the volume including a first volume fraction of the steel alloy and a second volume fraction of the copper alloy, and wherein the first volume fraction is in a range between ten percent and fifty percent of the volume of the composite.

4. The component according to claim 1, wherein the composite includes a volume, the volume including a first volume fraction of the steel alloy and a second volume fraction of the copper alloy, and wherein the first volume fraction is in a range between twenty-five percent and fifty percent of the volume of the composite.

5. The component according to claim 1, wherein the composite includes a volume, the volume including a first volume fraction of the steel alloy and a second volume fraction of the copper alloy, and wherein the first volume fraction and the second volume fraction are substantially equal to each other.

6. The component according to claim 1, wherein the steel alloy comprises a carbon steel alloy.

7. The component according to claim 6, wherein the carbon steel alloy comprises a mild steel alloy containing 0.05 wt %-0.25 wt % carbon.

8. The component according to claim 6, wherein the carbon steel alloy comprises a SAE 1080 steel alloy.

9. The component according to claim 1, wherein the steel alloy comprises a stainless steel alloy.

10. The component according to claim 9, wherein the stainless steel alloy comprises an austenitic stainless steel alloy.

11. The component according to claim 9, wherein the stainless steel alloy comprises a SAE 300-series austenitic stainless steel alloy.

12. The component according to claim 1, wherein the steel alloy comprises at least one of a carbon steel alloy and an austenitic stainless steel alloy.

13. The component according to claim 12, wherein the copper alloy comprises at least one of a copper-zinc alloy and an aluminum-bronze alloy.

14. The component according to claim 12, wherein the copper alloy comprises a naval brass alloy.

15. The component according to claim 14, wherein the composite includes a volume, the volume including a first volume fraction of the steel alloy and a second volume fraction of the naval brass alloy, and the first volume fraction and the second volume fraction being substantially equal to each other.

16. A method of making a component, the component including a body having a substrate surface, the method comprising:

applying, via thermal spray coating, a wear layer upon the body such that the wear layer is in overlying relationship with at least a portion of the substrate surface, the wear layer comprising a composite of a steel alloy and a copper alloy;

allowing the wear layer to solidify such that the wear layer is bonded to the body.

17. The method of making according to claim 16, wherein the body is made at least in part from a substrate material, and the steel alloy and the copper alloy of the composite are both different from the substrate material.

18. The method of making according to claim 16, wherein the thermal spray coating includes using a twin wire arc thermal spray machine.

19. The method of making according to claim 16, wherein the steel alloy comprises at least one of a carbon steel alloy and an austenitic stainless steel alloy, and wherein the copper alloy comprises at least one of a copper-zinc alloy and an aluminum-bronze alloy.

20. The method of making according to claim 16, further comprising:

machining the body to form the substrate surface, the substrate surface having a dimension with a value being less than a specification value;

wherein applying the wear layer to the body upon the body includes depositing the wear layer such that the value of the dimension when the wear layer is included therein is increased to be equal to or greater than the specification value.