Method for attaching a porous metal layer to a metal substrate

• US 9,656,358 B2
• Filed: 04/15/2013
• Issued: 05/23/2017
• Est. Priority Date: 06/18/2002
• Status: Active Grant

• Current Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Zawadzki, Steven, Charlebois, Steven, Hawkins, Michael E, Medlin, Dana, Gilbertson, Leslie N., Shetty, H. Ravindranath
• Primary Examiner(s): Kastler, Scott
• Assistant Examiner(s): Aboagye, Michael
• Application Number:
  US13/862,786
• Publication Number:
  US 20130219685A1
• Time in Patent Office: 1,499 Days
• Field of Search: 2282481, 228253, 228254, 2282623, 22826231, 22826271, 228245, 29445, 623 2353, 623 1611, 623 2336, 623 23- 55, 623 2356
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/30907 Nets or sleeves applied to surface of prostheses or in cement
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2002/30787 inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/30967 Diffusion bonding
• CPC Class Codes: A61F 2002/30968 Sintering
• CPC Class Codes: A61F 2002/30978 using electrical discharge machining [EDM]
• CPC Class Codes: A61F 2002/3401 with radial apertures, e.g. radial bores for receiving fixation screws
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00407 Coating made of titanium or of Ti-based alloys
• CPC Class Codes: A61F 2310/00544 Coating made of tantalum or Ta-based alloys
• CPC Class Codes: A61L 27/04 Metals or alloys
• CPC Class Codes: A61L 27/30 Inorganic materials
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: B22F 7/004 comprising at least one non-porous part
• CPC Class Codes: B22F 7/064 using an intermediate powder layer
• CPC Class Codes: B23P 23/00 Machines or arrangements of machines for performing specified combinations of different metal-working operations not covered by a single other subclass if the particular kinds of operation are not essential B23Q37/00 - B23Q41/00; working by laser beam combined with other working of metal B23K26/0093
• CPC Class Codes: C23C 26/00 Coating not provided for in groups C23C2/00 - C23C24/00
• CPC Class Codes: Y10T 29/49861 : Sizing mating parts during final positional association

Abstract

A method for attaching a porous metal layer to a dense metal substrate, wherein the method is particularly useful in forming orthopedic implants such as femoral knee components, femoral hip components, and/or acetabular cups. The method, in one embodiment thereof, comprises providing a solid metal substrate; providing a porous metal structure; contouring a surface of the porous metal structure; placing the porous structure against the substrate such that the contoured surface of the porous metal structure is disposed against the substrate, thereby forming an assembly; applying heat and pressure to the assembly in conjunction with thermal expansion of the substrate in order to metallurgically bond the porous structure and the substrate; and removing mass from the substrate after the porous structure is bonded to the substrate, thereby finish processing the assembly.

Claims

1. A method of forming an implantable orthopedic construct that includes a porous surface layer, comprising:

providing or obtaining an initial version of an orthopedic construct that includes an underlying metal substrate of a first mass metallurgically bonded to a porous metal surface layer by applying clamping pressure to and heating the underlying metal substrate of the first mass and the porous surface layer; and

reshaping the initial version of the orthopedic construct into a subsequent version of the orthopedic construct which includes removing mass from the underlying metal substrate of the first mass to form an underlying metal substrate of a second mass, wherein the underlying metal substrate of the first mass is significantly more massive than the underlying metal substrate of the second mass such that the underlying metal substrate of the first mass will exhibit greater thermal expansion when heated than would the underlying metal substrate of the second mass.

2. The method of claim 1, wherein the implantable orthopedic construct is a femoral knee component.

3. The method of claim 1, wherein the implantable orthopedic construct is a femoral hip component.

4. The method of claim 1, wherein the implantable orthopedic construct is an acetabular cup.

5. The method of claim 4, wherein the underlying metal substrate of the first mass is an unfinished acetabular cup substrate of a hemispherical shape.

6. The method of claim 5, wherein removing mass from the underlying metal substrate of the first mass includes hollowing out the hemispherical shape.

7. The method of claim 1, wherein the underlying metal substrate comprises a cobalt alloy or a titanium alloy.

8. The method of claim 7, wherein the titanium alloy is a Ti-6Al-4V alloy.

9. The method of claim 1, wherein the metallurgical bonds include bonding a sintered metal powder to the underlying metal substrate.