Patent Publication Number: US-2021180650-A1

Title: Bearing component with core and surface lattice structures

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/947,694 filed on Dec. 13, 2019, which is incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present invention is directed to a bearing component that has a core lattice structure and a cover formed over portions or all of the core lattice structure. 
     BACKGROUND 
     Bearings include any friction and wear-reducing machine component that aligns, guides, and supports moving parts. The bearing is often located between a moving part and a stationary part, acting as a connection point between the parts. 
     Traditional bearing designs use an inner component (e.g., spherical balls, inner race, shaft, stud, etc.) and an outer component (e.g. outer race, track roller, etc.) and roller elements (balls, needles, rollers, hourglass rollers, bearing cages, etc.). Bearing components are manufactured from solid masses of metal using subtractive manufacturing processes in which wrought, cast, or forged material is machined to remove material to obtain a desired shape. The solid metal configuration of typical bearing structures is a significant factor in the overall weight of the final bearing assembly. 
     In many assemblies, traditional bearings are too heavy and are unable to provide enhanced material properties required by design. In aerospace applications in particular (e.g., fixed wing aircraft and rotorcraft bearings), improved performance through weight reduction is a significant technology driver. State-of-the-art aerospace bearings employ costly manufacturing methods such as hollowing-out of steel or titanium balls, which requires expensive external coating processes (e.g., plasma spray or high velocity oxygen fuel—“HVOF”). 
     Existing methods of determining the extent of wear on bearing surfaces rely on observing component failure and evaluating the duration of in-service times. Wear on prior art bearing components can be localized in certain areas of the surface, such as high points on the surface. 
     There exists a need for a lightweight bearing that can still meet the same or increased structural demands of a metallic bearing component. There also exists a need for a bearing that clearly identifies when maintenance and/or replacement of the bearing is required. 
     SUMMARY 
     The present invention includes a light-weight bearing component for sliding or rolling engagement with a mating surface. The light-weight bearing component includes a core lattice structure that has a plurality of support members interconnected with one another and a plurality of spaces located between the support members. The light-weight bearing component includes a cover that has an interior surface and an exterior surface. The cover extends over the entire core lattice structure or a portion thereof. 
     In some embodiments, the light-weight bearing component includes a surface lattice structure that extends from (e.g., continuously and outwardly) the exterior surface of the cover and/or a roughened area on the exterior surface of the cover. 
     In some embodiments, the core lattice structure, the cover, the surface lattice structure and/or the roughened area are formed by an additive manufacturing process. 
     In some embodiments, the surface lattice structure and/or the roughened area has an adhesive (e.g., an adhesive resin such as an epoxy resin) therein and a self-lubricating liner is adhered to the surface lattice structure and/or the roughened area by the adhesive. 
     In some embodiments, one or more sensors extend outwardly from the cover and into the self-lubricating liner. The sensors are configured to measure thickness of the self-lubricating liner. In some embodiments, the self-lubricating liner includes polytetrafluoroethylene (PTFE). 
     In some embodiments, the surface lattice structure and/or the roughened area form a receiving area and a lubricant layer is disposed on and extending into the receiving area. In some embodiments, one or more sensors extend outwardly from the cover and into the lubricant layer. The sensors are configured to measure thickness of the lubricant layer. In some embodiments, the lubricant layer includes polytetrafluoroethylene (PTFE). 
     In some embodiments, two or more of the plurality of support members are integral with each other. 
     In some embodiments, two or more of the plurality of support members are connected to each other with a reinforcing member. 
     In some embodiments, the cover is formed integrally with the core lattice structure and/or the surface lattice structure is formed integrally with the cover. 
     In some embodiments, the cover is secured to the core lattice structure and/or the surface lattice structure is secured to the cover. 
     In some embodiments, the core lattice structure and the cover cooperate to provide a uniform load carrying configuration on the cover. 
     The present invention includes a light-weight bearing assembly that has an outer member bearing component and an inner member bearing component disposed partially in the outer member bearing component. The inner member bearing component and the outer member bearing component are rotatable with respect to each other. The light-weight bearing assembly includes a first core lattice structure that has a plurality of first support members interconnected with one another and a plurality of first spaces located between the first support members. The outer member bearing component has a first cover which has a first exterior surface. The first cover extends over at least a portion of the first core lattice structure. The light-weight bearing assembly includes a second core lattice structure that has a plurality of second support members interconnected with one another and a plurality of second spaces located between the second support members. The inner member bearing component has a second cover which has a second exterior surface. The second cover extends over at least a portion of the second core lattice structure. 
     In some embodiments, a first surface lattice structure or a first roughened area is on the first exterior surface the first cover and the second exterior surface is a first smooth bearing surface. In some embodiments, and a second surface lattice structure or a second roughened area is on the second exterior surface the second cover and the first exterior surface is a second smooth bearing surface. 
     In some embodiments, one of the first surface lattice structure, the second surface lattice structure, the first roughened area and the second roughened area has one of a lubricant layer and a self-lubricating liner thereon. 
     The present invention includes a method of manufacturing a light-weight bearing component. The method includes providing an additive manufacturing system. The method further includes selecting one or more powder materials based upon service parameters of the bearing component and designing a core lattice structure based upon the service parameters of the bearing component. The core lattice structure is made using the additive manufacturing system and using powder materials. 
     In some embodiments, the method includes applying a cover on the core lattice structure using the additive manufacturing system; and additive manufacturing a surface lattice structure on (e.g., extending continuously and outwardly from) the exterior surface of the cover and/or a roughened area on the exterior surface of the cover. 
     In some embodiments the method includes applying an adhesive (e.g., an adhesive resin such as an epoxy resin) to the surface lattice structure and/or the roughened area and adhering a self-lubricating liner to the surface lattice structure and/or the roughened area by the adhesive. 
     In some embodiments the method includes forming a receiving area in the surface lattice structure and/or the roughened area and disposing a lubricant layer on and extending into the receiving area. 
     The present invention includes a method of manufacturing a light-weight bearing component. The method includes providing an additive manufacturing system and selecting one or more powder materials based upon service parameters of the bearing component. The method includes designing a core lattice structure, a surface lattice structure and a cover using multiple powder materials of varying hardness and strength. The step of varying the hardness and strength of the core lattice structure, the surface lattice structure and the cover optimizes the properties of thereof to meet load requirements and wear requirements. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front view of an inner member bearing component according to the present disclosure; 
         FIG. 2A  is a cross-sectional view of the inner member bearing component of  FIG. 1  taken along section A-A of  FIG. 1 ; 
         FIG. 2B  is a cross-sectional view of the outer member bearing component of the present disclosure; 
         FIG. 2C  is a cross-sectional view of a spherical bearing assembly having the inner member bearing component of  FIG. 2A  disposed in the outer member bearing component of  FIG. 2B ; 
         FIG. 2D  is a cross-sectional view of the inner member bearing component with a cover with an opening therein; 
         FIG. 2E  is an enlarged view of a portion of the inner member bearing component of  FIG. 2D  showing Detail  2 E; 
         FIG. 2F  is a side view of  FIG. 2D  showing the opening in the cover and viewed in Section  2 F, 2 G- 2 F, 2 G of  FIG. 2D ; 
         FIG. 2G  is a side view of  FIG. 2D  showing the opening in the cover with webs extend across the opening and viewed in Section  2 F,  2 G- 2 F,  2 G of  FIG. 2D ; 
         FIG. 3  is a partial cross-sectional view of an alternative bearing component according to the present disclosure; 
         FIG. 4  is a partial cross-sectional view of an alternative bearing component according to the present disclosure; 
         FIG. 5  is a partial cross-sectional view of an alternative bearing component according to the present disclosure; 
         FIG. 6  is a partial cross-sectional view of an alternative bearing component according to the present disclosure; 
         FIG. 7  is a partial perspective cross-sectional view the bearing component of  FIG. 6 ; 
         FIG. 8A  is a partial cross-sectional view of the bearing component of  FIG. 6  including a lubricant layer; 
         FIG. 8B  partial cross-sectional view of the bearing component of  FIG. 6  including a self-lubricating liner and an adhesive; 
         FIG. 8C  is a perspective view of the self-lubricating liner of  FIG. 8B ; 
         FIG. 8D  is perspective cross-sectional view of a bearing component of the present invention showing the cover with a roughened surface; 
         FIG. 8E  is a cross-sectional view of  FIG. 8D  with an adhesive on the roughened surface and the self-lubricating liner of  FIG. 8C  secured to the roughened surface by the adhesive; 
         FIG. 9  depicts a number of alternative lattice structures compatible with the bearing component disclosed herein; and 
         FIG. 10  depicts additional alternative lattice structures compatible with the bearing component disclosed herein. 
     
    
    
     DETAILED DESCRIPTION 
     As shown in  FIG. 2C , a light-weight spherical bearing assembly is generally designated by the reference number  100 . The light-weight spherical bearing assembly  100  includes an inner member bearing component which is generally designated by the numeral  10  and an outer member bearing component which is generally designated by the numeral  70 . The outer member bearing component  70  has a radially inward facing concave spherical surface  64  that defines an interior area  68  of the outer member bearing component  70 . The outer member bearing component  70  has a cylindrical exterior surface  60 C. The radially inward facing concave spherical surface  64  and a cylindrical exterior surface  60 C each extend between a first axial end  60 A and a second axial end  60 B of the outer member bearing component  70 . The inner member bearing component  10  has a radially outward facing convex spherical surface  24 . The inner member bearing component  10  is disposed partially in the interior area  68  of the outer member bearing component  70 . The inner member bearing component  10  and the outer member bearing component  70  are configured to angularly misalign (e.g., rotatable with respect to each other) relative to each other such that the radially outward facing convex spherical surface  24  and the radially inward facing concave spherical surface  64  slide against each other. 
     Referring to  FIG. 2A , the inner member bearing component  10  includes a cover  20  which has an interior surface  22  and the radially outward facing convex spherical surface  24  which is formed as part of the cover  20 . The interior surface  22  defines an interior area  26  of the inner member bearing component  10 . A three-dimensional core lattice structure  30  is disposed within the interior area  26 . The core lattice structure  30  is formed by a plurality of support members  32  interconnected with one another. A plurality of spaces  34  are located between the support members  32 . The cover  20  illustrated in  FIG. 2A  extends over the entire lattice structure  30 . However, the present invention is not limited in this regard as other configurations may be employed, including, but not limited to, the cover  20  extending over one or more portions of the core lattice structure  30  and/or the cover  20  having one or more openings therein as shown and described herein with reference to  FIGS. 2D, 2E, 2F and 2G , for example. 
     As shown in  FIGS. 2D, 2E, 2F and 2G  the cover  20  has an opening  29  extending through the second axial end  20 B of the cover  20  for the inner member bearing component  10 . In the embodiment shown in  FIG. 2F , the opening  29  extends entirely and continuously circumferentially around the second axial end  20 B. In the embodiment shown in  FIG. 2G , the opening  29  extends intermittently circumferentially around the second axial end  20 B and is interrupted by radially extending webs  29 X. While the opening  29  is shown in the second axial end  20 B of the cover  20  for the inner member bearing component  10 , the present invention is not limited in this regard as other configurations are contemplated including, but not limited to, more than one opening in the cover  20  of the inner member bearing component  10  and one or more openings in the cover  60  of the outer member bearing component  70 . 
     Referring to  FIG. 2B , the outer member bearing component  70  includes a cover  60  which has an interior surface  62  and the radially inward facing concave spherical surface  64  which is formed as part of the cover  60 . The interior surface  62  defines an interior area  66  of the outer member bearing component  70 . Similar to that described herein for the inner member bearing component  10 , the outer member bearing component  70  has the three-dimensional core lattice structure  30  is disposed within the interior area  66 . The core lattice structure  30  is formed by the plurality of support members  32  interconnected with one another. The plurality of spaces  34  are located between the support members  32 . The cover  60  illustrated in  FIG. 2B  extends over the entire lattice structure  30 . However, the present invention is not limited in this regard as other configurations may be employed, including, but not limited to, the cover  60  extending over one or more portions of the core lattice structure  30  and/or the cover  60  having one or more openings therein similar to those described herein with reference to  FIGS. 2D, 2E, 2F and 2G , for example. 
     Referring to  FIG. 2A , the cover  20  for the inner member bearing component  10  is secured to the core lattice structure  30 . The cover  20  has a convex spherical section  20 X that extends between a first axial end  20 A and a second axial end  20 B of the cover  20 . The cover  20  includes a cylindrical surface  20 C that extends between the first axial end  20 A and a second axial end  20 B and is located radially inward from the convex spherical section  20 X. The cover  20  has utility in a bearing assembly as an inner ring of the spherical bearing  100 . 
     Referring to  FIG. 2B , the cover  60  for the outer member bearing component  70  is secured to another core lattice structure  30 . The cover  60  has a concave spherical section  60 X that extends between a first axial end  60 A and a second axial end  60 B of the cover  60 . The cover  60  includes a cylindrical exterior surface  20 C that extends between the first axial end  60 A and a second axial end  60 B and is located radially outward from the concave spherical section  60 X. The cover  60  has utility in a bearing assembly as an outer ring of the spherical bearing  100 . 
     As shown in  FIG. 2A , the interior surface  22  of the cover  20  is secured (e.g., via an adhesive such as epoxy or phenolic resin, formed integrally with the cover via an additive manufacturing process or via material joining processes such as welding) to support member ends  32 A,  32 B of the plurality of supports  32 . In one embodiment, the cover  20  is made from a harder material than the core lattice structure  30 . The cover  20  is bonded to the core lattice structure  30  via structural adhesive (e.g., an adhesive such as epoxy or phenolic resin) or welding. In some embodiments, the cover  20  is integrally formed with the core lattice structure  30  via an additive manufacturing process. The support member ends  32 A,  32 B of each support member  32  are secured to, define and maintain the contour of the interior surface  22  of the cover  20 . In one embodiment, the location of the support member ends  32 A,  32 B of the support members  32  define and maintain the shape of the radially outward facing convex spherical surface  24  of the cover  20 . 
     As shown in  FIG. 2B , the interior surface  62  of the cover  60  is secured (e.g., via an adhesive such as epoxy or phenolic resin, formed integrally with the cover via an additive manufacturing process or via material joining processes such as welding) to support member ends  32 A,  32 B of the plurality of supports  32 . In one embodiment, the cover  60  is made from a harder material than the core lattice structure  30 . The cover  60  is bonded to the core lattice structure  30  via structural adhesive (e.g., an adhesive such as epoxy or phenolic resin) or welding. In some embodiments, the cover  60  is integrally formed with the core lattice structure  30  via an additive manufacturing process. The support member ends  32 A,  32 B of each support member  32  are secured to, define and maintain the contour of the interior surface  62  of the cover  60 . In one embodiment, the location of the support member ends  32 A,  32 B of the support members  32  define and maintain the shape of the radially inward facing concave spherical surface  64  of the cover  60 . 
     As shown in  FIG. 2A , the cover  20  has a thickness T 1  which is measured between the interior surface  22  and the radially outward facing convex spherical surface  24 . The thickness T 1  and/or the material of the cover  20  are selected and configured to ensure that the radially outward facing convex spherical surface  24  of the cover  20  remains rigid during use of the bearing component  10 . In one embodiment, the thickness T 1  of the cover  20  has two or more different thicknesses. For example, the cover  20  has thicker portions at specific locations that experience higher wear or stress, for example portions of the cover  60  that extend between adjacent support member ends  32 A or between adjacent support member ends  32 B. In one embodiment, the convex spherical section  20 X is thicker that the first axial end  20 A and the second axial end  20 B and the cylindrical surface  20 C. In one embodiment the first axial end  20 A and the second axial end  20 B are thicker than the convex spherical section  20 X and the cylindrical surface  20 C. 
     As shown in  FIG. 2B , the cover  60  has a thickness T 1  which is measured between the interior surface  62  and the radially inward facing concave spherical surface  64 . The thickness Ti and/or the material of the cover  60  are selected and configured to ensure that the radially inward facing concave spherical surface  64  of the cover  60  remains rigid during use of the outer member bearing component  70 . In one embodiment, the thickness T 1  of the cover  60  has two or more different thicknesses. For example, the cover  60  has thicker portions at specific locations that experience higher wear or stress, for example portions of the cover  60  that extend between adjacent support member ends  32 A or between adjacent support member ends  32 B. In one embodiment, the concave spherical section  60 X is thicker that the first axial end  60 A and the second axial end  60 B and the exterior cylindrical surface  60 C. In one embodiment the first axial end  60 A and the second axial end  60 B are thicker than the convex spherical section  60 X and the cylindrical surface  60 C. 
     As shown in  FIGS. 5 and 8A , the thickness T 1  of the cover  20 ′ and the distance W 1  between adjacent support members  32  are selected via an iterative analysis and computation to address the problem of localized deflection of the cover  20 ′, as indicated by the dashed lines between adjacent support members  32  which results in high points HP on the exterior surface  24 ′. The inventors have surprisingly discovered that selection of a predetermined thickness T 1  of the cover  20 ,  20 ′,  60  along with a predetermined distance W 1  between adjacent support members  32  minimizes or eliminates the localized deflection of the cover  20 ′ and eliminates the potential for the high points HP that wear at a higher rate than the localized deflections. In some embodiments, the material of the cover  20 ,  20 ′,  60  is made from a variety of materials of different strengths. For example, portions of the cover  20 ,  20 ′,  60  extending between the support members  32  is manufactured of a material with a higher strength than the material of other portions of the cover  20 ,  20 ′,  60 . In some embodiments, the portions of the cover  20 ,  20 ′,  60  extending between the support members  32  have a build-up of material on the inside surface  22 ′ to add strength to the cover  20 ,  20 ′,  60 . In some embodiments, the portions of the cover  20 ,  20 ′,  60  extending between the support members  32  reinforcing materials such as fibers therein to add strength to the cover  20 ,  20 ′,  60 . Thus, the core lattice structure  30  (e.g., the distance W 1  between support members  32 ) and the cover (e.g., thickness and material of the cover) cooperate to provide a uniform load carrying configuration on the cover  20 ,  20 ′,  60 . 
     In some embodiments, the cover  20 ,  20 ′,  60  has a surface hardening treatment (nitriding, carbo-nitriding) thereon to reduce wear of the cover  20 ,  20 ′,  60 . The inventors have surprisingly found that although the core lattice structure  30  creates a non-uniform heat transfer characteristic of the cover  20 ,  20 ′, 60 , that selective surface hardening of the cover  20 ,  20 ,′  60  increases the wear resistance of the cover  20 ,  20 ′,  60 . 
     As shown in  FIG. 3 , the support member ends  32 A extend into the cover  20  of the inner member bearing component  10 . In the embodiment shown in  FIG. 4 , the support member ends  32 A extend through and protrude out of the radially outward facing convex spherical surface  24  of the cover  20 . As shown in  FIG. 5 , the support members  32 ′ are formed integrally with the cover  20 ′. As shown in  FIGS. 6, 7 and 8 , the support members  32 ′ are formed integrally with the cover  20 ′. The support member ends  32 A of the outer member bearing component  70  are configured similar to the support member ends  32 A of the inner member bearing component  10  including the configurations shown are configured similar to the support member ends  32 A as shown in  FIGS. 3, 4, 5, 6 and 7  with the exception that the support member ends  32 A extend through and protrude out of the radially inward facing concave spherical surface  64 . The support member ends  32 B of the inner member bearing component  10  and the outer member bearing component  70  are configured similar to the support member ends  32 A as shown in  FIGS. 3, 4, 5, 6 and 7 . 
     Referring to  FIGS. 2A and 2B , a reinforcing member  36  connects adjacent support members  32  to one another. The reinforcing members  36  are placed at specific locations on the support members  32  to join intersecting support members  32  to one another and to provide additional strength to the core lattice structure  30  to better withstand external forces and wear. The reinforcing members  36  are a buildup of material on and around a juncture between intersecting support members  32 . In some embodiments, the reinforcing members  36  include fiber strands. 
     While cover  20  shown and described with reference to  FIG. 2A  has the convex spherical section  20 X and the cylindrical surface  20 C both of which extend between the first axial end  20 A and the second axial end  20 B, the present invention is not limited in this regard as other configurations may be employed including but not limited to the concave spherical section  60 X and the exterior cylindrical section  60 C both extending between the first axial end  60 A and the second axial end  60 B as shown in  FIG. 2B  and other cross-sectional shapes such as cylindrical shapes. 
     In one embodiment, as depicted in  FIG. 3 , the support members  32  of the inner member bearing component  10  are integral with each other. In other words, the plurality of support members  32  form a unitary core lattice structure  30 . Each of the depicted support members  32  has a support member end  32 A that extends through the interior surface  22  into the cover  20 . In the embodiment depicted in  FIG. 3 , the support member ends  32 A do not extend through the radially outward facing convex spherical surface  24 . In some embodiments, the support members  32  of the outer member bearing component  70  are configured similar to the support members  32  of the inner member bearing component  10  shown in  FIG. 3 . 
     Referring to  FIG. 4 , the support members  32  of the inner member bearing component  10  extend through the interior surface  22  and through the radially outward facing convex spherical surface  24  of the cover  20 . A portion of the core lattice structure  30  extends outwardly from the radially outward facing convex spherical surface  24  of the cover  20 . In some embodiments, the support members  32  of the outer member bearing component  70  are configured similar to the support members  32  of the inner member bearing component  10  shown in  FIG. 4 . 
     Referring to  FIG. 5 , the cover  20 ′ for the inner member bearing component  10  is integral with the core lattice structure  30 ′. The support members  32 ′ extend through the interior surface  22 ′ of the cover  20 ′ but do not extend through the radially outward facing convex spherical surface  24 ′ of the cover  20 ′. In some embodiments, the support members  32 ′ of the outer member bearing component  70  are configured similar to the support members  32 ′ of the inner member bearing component  10  shown in  FIG. 5 . 
     In the embodiment depicted in  FIGS. 6, 7,8A, 8B, 8D and 8E  the cover  20 ′ for the inner member bearing component is integral with the core lattice structure  30 ′. As shown in  FIGS. 8A and 8B , a portion of the core lattice structure  30 ′ extends outwardly from the radially outward facing convex spherical surface  24 ′ of the cover  20 ′ (i.e., the support member ends  32 A′ protrude away from the exterior surface  24 ′). The support member ends  32 A′ extend from the radially outward facing convex spherical surface  24 ′ of the cover to form receiving areas  28  for receiving a lubricant layer  40  (depicted in  FIG. 8A ). The lubricant layer  40  is disposed on (e.g., spread on, molded on, directly bonded on, cured on or formed on) and extends into the receiving areas  28 . The lubricant layer  40  extends a thickness T 2 , measured perpendicularly and radially outward from the radially outward facing convex spherical surface  24 ′ of the cover  20 ′. In the embodiment depicted in  FIG. 8A , the lubricant layer  40  extends a thickness T 3  radially outward from the radially outward facing convex spherical surface  24 ′, measured from the outermost edge of the support member ends  32 A′. In some embodiments, the lattice structure  30 ′ of the outer member bearing component  70  is configured similar to the lattice structure  30 ′ of the inner member bearing component  10  illustrated in FIGS.  FIGS. 6, 7, 8A, 8B, 8D and 8E  with the exception that the lubricant layer  40  extends a thickness T 2 , measured perpendicularly and radially inward from the radially inward facing concave spherical surface  64  of the cover  60 . 
     While the lubricant layer  40  is shown and described as being disposed on the receiving area via spreading, molding, direct bonding, curing or forming, the present invention is not limited in this regard as a self-lubricating liner  40 ′ as shown in  FIG. 8C  having a thickness T 20  may be applied to the receiving area  28  and on the radially outward facing convex spherical surface  24 ′ using an adhesive layer  50  (e.g., an epoxy or phenolic resin), as shown in  FIG. 8B . A bonding side  40 B of the self-lubricating liner  40 ′ conforms to the contour formed by the receiving area  28  and on the radially outward facing convex spherical surface  24 ′ while an exposed surface  40 A of the of the self-lubricating liner  40 ′ retains a uniform shape. 
     In the embodiment depicted in  FIG. 8A , a protuberance  42  extends outwardly from the cover  20 ′,  60 . In one embodiment, the protuberance  42  is a sensor configured to measure thickness of the lubricant layer  40 . The protuberance  42  provides a visual indicator of the extent of wear of the friction-reducing surface finish or lubricant layer  40 . The protuberance  42  provides a dimensionally-quantitative verification basis for recommendations for component replacement or refinishing of the lubricant layer  40  or self-lubricating liner  40 ′. 
     As shown in  FIGS. 8D and 8E , the receiving area  28  is formed on the cover  20 ,  20 ′,  60 , in the form of a roughened area  24 ″ on the radially outward facing convex spherical surface  24 ′, and a self-lubricating liner  40 ′ is applied to the roughened area  24 ″. Direct bonding of the self-lubricating liner  40 ′ (e.g., PTFE, fabric composite matrix, PTFE molded liner systems, machinable liner systems) to the roughened surface saves time and provides uniformity improvements over prior art processes. In one embodiment, the roughened area  24 ″ receives an adhesive resin  50  (e.g., an adhesive such as epoxy or phenolic resin) that aids in the bonding of the self-lubricating liner  40 ′ to the roughened area  24 ″. In other embodiments, the lubricant layer  40  is disposed on (e.g., spread on, molded on, directly bonded on, cured on or formed on) the roughened area  24 ″. 
     As shown in  FIG. 2C , the light-weight bearing assembly  100  includes the outer member bearing component  70  and the inner member bearing component  10  that is disposed partially in the outer member bearing component  70 . The inner member bearing component  10  and the outer member bearing component  70  are rotatable with respect to each other. The light-weight bearing assembly  10  includes a first core lattice structure  30  having a plurality of first support members  32  interconnected with one another and a plurality of first spaces  34  located in the interior area  26  between the first support members  32 . The outer member bearing component  70  has a first cover  60  having a first exterior surface  64 ,  60 C,  60 A and  60 B. The first cover  60  extends over at least a portion of the first core lattice structure  30 . The outer member bearing component  70  includes a second core lattice structure  30  that has a plurality of second support members  32  interconnected with one another and a plurality of second spaces  34  located between the second support members  32 . The inner member bearing component  10  having a second cover  20  having a second exterior surface  24 ,  20 A,  20 B and  20 C. The second cover  20  extends over at least a portion of the second core lattice structure  30 . In some embodiments, the light-weight bearing assembly  100  includes a first surface lattice structure  130  (see  FIG. 7 ) or a first roughened area  24 ″ (see  FIG. 8D ) on the first exterior surface  24 ′ the first cover  20  and the second exterior surface  64  being a first smooth bearing surface. In some embodiments, the light-weight bearing assembly  100  includes a second surface lattice structure  130  or a second roughened area  28  on the second exterior surface the second cover and the first exterior surface being a second smooth bearing surface. 
     In some embodiments, the first surface lattice structure, the second surface lattice structure, the first roughened area and the second roughened area of the light-weight bearing assembly  100  has either a lubricant layer or a self-lubricating liner thereon. 
     In one embodiment, the lubricant layer  40  and the self-lubricating liner  40 ′ are made from polytetrafluoroethylene (PTFE), but similar low friction polymeric materials do not depart from the present disclosure. 
     In one embodiment, as depicted in  FIG. 7 , inner member bearing component  10 ′, and the outer member bearing component  70  includes a surface lattice structure  130  that is formed integrally with the cover  20 ′,  60 . The surface lattice structure  130  extends continuously and outwardly from the cover  20 ′,  60 . The surface lattice structure  130  includes load carrying plateaus  35  between the receiving areas  28  for the lubricant layer  40 , self-lubricating liner  40  and adhesive  50  to be disposed in. In some embodiments, the receiving areas  28  contains a supply of lubricant (e.g., grease or a dry lubricant powder) that is dispensed over the load-bearing plateaus  35  and in the receiving area  28 . The lubricant reduces friction during normal oscillatory motion of the bearing component  10 ′. The lubricant provides continuous lubrication of the connection points between the stationary and moving parts of the bearing component  10 ′,  70  and/or between two moving parts of the bearing assembly. 
     While the inner member bearing component  10  and the outer member bearing component  70  is shown and described as having the surface lattice structure  130  that is formed integrally with the cover  20 ′,  60 , the present invention is not limited in this regard as other configurations are contemplated including but not limited to the surface lattice structure  130  being formed separately from the cover  20 ′,  60  and secured thereto by a suitable bonding process (e.g., adhesive bonding, welding or brazing). 
     The inner member bearing component  10 ,  10 ′, the outer member bearing component  70  including the core lattice structure  30 ,  30 ′, the support members  32 ,  32 ′, the cover  20 ,  20 ′, the roughened surface  24 ″, the lubricant layer  40  and the self-lubricating liner  40 ′ are formed using an additive manufacturing system. The additive manufacturing system selects at least one powder material based upon service parameters of the bearing component  10  (e.g., strength, weight, heat resistance, conductivity). A core lattice structure  30  is designed based upon the service parameters of the bearing component  10 . The core lattice structure  30  is created by the powder material using the additive manufacturing system and a cover  20  is applied on the core lattice structure  30 . 
       FIGS. 9 and 10  depict examples of alternative lattice structures compatible with the inner member bearing component  10 ,  10 ′ and the outer member bearing component  70  disclosed herein. In  FIG. 9 , the lattice structure  30 ″ has support members  32 ″ that have a greater volume relative to the spaces  34 ″ at a first end  30 A″ than at a second end  30 B″. The support members  32 ″ decrease in volume relative to the spaces  34 ″, in other words the spaces  34 ″ between the support members  32 ″ increases, from the first end  30 A″ to the second end  30 B″. The lattice structures  30 Q 3  and  30 Q 4 , as depicted in  FIG. 9 , have a random arrangement or a pseudo-random arrangement of support members  32 Q 3 ,  32 Q 4 . In one embodiment, as depicted in  FIG. 10 , the lattice structure  30 Q 5  has hollow support members  32 Q 5 , with spaces  34 Q 5  between the support members  32 Q 5  and within each of the support members  32 Q 5 . 
     The design of the core lattice structure and/or the composition of the powder material is chosen to mechanically optimize the bearing design while also improving the wear resistance of the bearing. The use of the additive powder material (e.g., metals, polymers, fibers, mixtures, etc.) allows further customization of the material beyond those materials produced at the foundry level. 
     The method of additive manufacturing the bearing component  10  disclosed herein allows tailoring of the material composition to optimize the function of the core lattice structure  30  as a whole (e.g., to strengthen the core lattice structure  30 ) or by using different powders and/or materials in different parts of the same core lattice structure  30  to enhance wear (e.g., at contact surfaces). In one embodiment, the design of the core lattice structure and cover incorporates using multiple powder materials of varying hardness and strength. The hardness and strength of the core lattice structure and the cover can vary to optimize the properties of the core lattice structure and the cover to meet load requirements and wear requirements. 
     Utilizing internal cellular architectures, such as the core lattice structure  30  disclosed herein in bearing components  10 ,  10 ′, provides a 10% to 50% reduction in mass as compared to prior art bearing components manufactured using subtractive manufacturing processes. 
     Although this invention has been shown and described with respect to the detailed embodiments thereof, it will be understood by those of skill in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed in the above detailed description, but that the invention will include all embodiments falling within the scope of the appended claims.