Bearing assemblies including at least one superhard bearing element having selected surface characteristics and methods of manufacture
Embodiments of the invention related to bearing assemblies and methods of forming the bearing assemblies that include at least one superhard bearing element exhibiting a superhard bearing surface having a polished surface finish or a superhard bearing surface having a textured surface. In an embodiment, a bearing assembly includes a support ring. The bearing assembly includes at least one superhard bearing element. The at least one superhard bearing element includes a superhard bearing surface having a polished surface finished or a textured surface. The at least one superhard bearing element is secured to the support ring.
1. An assembly comprising:
a bearing assembly including a support ring and at least one superhard bearing element including a superhard bearing surface comprising polycrystalline diamond and having an at least partially polished surface finish that exhibits an R a surface finish of about 0.0025 μm or less, the at least one superhard bearing element secured to the support ring; and
at least one packaging material adjacent to the support ring and the at least one superhard bearing element, the at least one packaging material configured to protect the at least partially polished surface finish of the at least one superhard bearing element.
2. The assembly of claim 1 , wherein the at least partially polished surface finish exhibits an R a surface finish of about 0.0013 μm or less.
3. The assembly of claim 1 , wherein the at least partially polished surface finish exhibits an R a surface finish of about 0.00025 μm or less.
4. The assembly of claim 1 , wherein the at least one superhard bearing element includes a plurality of superhard bearing elements secured to the support ring, each of the plurality of superhard bearing elements having a superhard bearing surface having an at least partially polished surface finish, the superhard bearing surfaces being substantially coplanar with each other.
5. The assembly of claim 1 , wherein the at least partially polished surface finish does not uniformly cover the superhard bearing surface.
6. The assembly of claim 1 , wherein the at least partially polished surface finish only covers a portion of the superhard bearing surface.
7. The assembly of claim 1 , wherein the at least one superhard bearing element includes at least one of: a plurality of sliding superhard bearing elements, a plurality of tilting pads, or a substantially continuous superhard bearing element.
8. A method of forming a bearing assembly, the method comprising:
providing at least one superhard bearing element that has not been worn in during operation of a bearing apparatus including the at least one superhard bearing element, the at least one superhard bearing element including a superhard bearing surface comprising polycrystalline diamond;
leaching the at least one superhard bearing element to at least partially remove a catalyst material from the polycrystalline diamond;
providing a support ring configured to support the at least one superhard bearing element;
polishing at least a portion of the superhard bearing surface of the at least one superhard bearing element to exhibit a polished surface finish, the polished surface finish exhibiting an R a surface finish of about 0.0025 μm or less; and
securing the at least one superhard bearing element to the support ring.
9. The method of claim 8 , wherein the act of securing the at least one superhard bearing elements to the support ring occurs prior to the act of polishing the superhard bearing surface of the at least one superhard bearing element to exhibit a polished surface finish.
10. The method of claim 9 , wherein the at least one superhard bearing element includes a plurality of superhard bearing elements each of which includes a superhard bearing surface, and wherein polishing the at least a portion of the superhard bearing surface of the at least one superhard bearing element to exhibit a polished surface finish includes polishing the superhard bearing surface of each of the plurality of superhard bearing elements such that the superhard bearing surfaces are substantially coplanar with each other.
11. The method of claim 8 , further comprising providing another, substantially similar superhard bearing surface, wherein polishing at least a portion of the superhard bearing surface of the at least one superhard bearing element includes polishing the superhard bearing surface to exhibit a coefficient of friction of about 0.02 or less when in contact with another, substantially similar superhard bearing surface.