Production of porous coating on a prosthesis

Claim 3

The method of claim 1, wherein the step of covering the metallic substrate area comprises: mixing a preselected proportion of primary and secondary particles with a binder in a homogenously blended mixture; and applying the blended mixture of particles and binder onto the metallic substrate area at a dimensional thickness greater than that of the resulting porous coating.

Claim 4

The method of claim 2 wherein the step of applying the blended mixture is accomplished by first spreading the mixture over surface areas of punches complementary to the metallic substrate area.

Claim 5

The method of claim 1 wherein the step of covering the metallic substrate area comprises: mixing a preselected proportion of primary and secondary particles with a binder in a homogenously blended mixture; applying the blended mixture of particles and binder onto the metallic substrate area at a dimensional thickness greater than that of the resulting porous coating; and curing the binder to secure the blended mixture of primary and secondary particles onto the metallic substrate area.

Claim 6

The method of claim 1 wherein the blended mixture of primary and secondary particles is maintained in a homogeneous state by adding to it a liquid binder prior to covering the metallic substrate area of the prosthesis.

Claim 7

The method of claim 1 wherein the metallic substrate area of the prosthesis and the primary particles are each composed of Ti6A14V alloy; said elevated temperature being below the beta transus temperature for the alloy.

Claim 10

The method of claim 7 wherein the compressing step reduces the thickness of the coating by 10% to 30%.

Claim 11

The method of claim 7 wherein the step of filling the space between the metallic substrate area and mold cavity surfaces is accomplished by directing a dry blend of primary and secondary particles between them.

Claim 12

The method of claim 7 wherein the step of filling the space between the metallic substrate area and mold cavity surfaces is accomplished by directing a dry blend of primary and secondary particles between them; and bonding the primary particles to one another and to the metallic substrate area by gravity sintering prior to compressing them while at the elevated temperature.

Claim 13

The method of claim 7 wherein the step of filling the space between the metallic substrate area and mold cavity surfaces is accomplished by directing a blend of primary and secondary particles between them, plus a liquid binder.

Claim 14

The method of claim 7 wherein the step of filling the space between the metallic substrate area and mold cavity surfaces is accomplished by directing a homogeneously blended mixture of a binder and primary and secondary particles between them.

Claim 15

The method of claim 7 wherein the step of filling the space between the metallic substrate area and mold cavity surfaces is accomplished by directing a homogeneously blended mixture of a binder and primary secondary particles between them; and curing the binder to thereby attach the primary and secondary particles to the metallic substrate area prior to compressing them at the elevated temperature.

Claim 16

The method of claim 7 wherein the step of filling the space between the metallic substrate area and mold cavity surfaces is accomplished by spreading a homogeneously blended mixture of a binder and primary and secondary particles over the mold cavity surfaces prior to positioning the prosthesis within the mold cavity formed thereby.

Claim 19

The method of claim 15 wherein the compressing step produces the desired surface configuration on the coating about the preselected substrate area of the prosthesis.

Claim 20

The method of claim 15 further comprising the step of bonding the primary particles to one another and to the metallic substrate area by gravity sintering prior to compressing them while at the elevated temperature.

Claim 21

The method of claim 15 further comprising the step of bonding the primary particles to one another and to the metallic substrate area by gravity sintering prior to compressing them while at the elevated temperature; and the compressing step being carried out by hot isostatic pressing or by compression within a multiple-segment die.

Claim 22

The method of claim 15 wherein the expendable material is removed by chemical processing steps.

Claim 23

The method of claim 15 wherein the metallic substrate area of the prosthesis and the primary particles are each composed of Ti6A14V alloy; said elevated temperature being below the beta transus temperature for the alloy.

Claim 24

A prosthesis for tissue ingrowth applications, comprising: a structural metallic substrate; and a coating in the form of a matrix presented by randomly dispersed discrete metal particles having a substantially uniform size joined to one another and to the substrate by metallurgical bonds, the particles and substrate being compressibly deformed to present an outer coating surface conforming to the size and configuration of a mold in which they were compressed and of proper dimensions for implant purposes without machining; the metal particles being separated from one another by a network of interconnected voids having an average size greater than the average size of the discrete metal particles to present a homogeneously porous coating about the substrate.

Claim 25

A prosthesis for tissue ingrowth applications, comprising: a structural metallic substrate; and a coating in the form of a matrix presented by randomly dispersed discrete metal particles having a substantially uniform size joined to one another and to the substrate by metallurgical bonds, the particles and substrate being compressibly deformed to present an outer coating surface conforming to the size and configuration of a mold in which they were compressed and of proper dimensions for implant purposes without machining; the metal particles being separated from one another by a network of interconnected voids having an average size greater than the average size of the discrete metal particles to present a homogeneously porous coating about the substrate.

Claim 26

The prosthesis of claim 21 wherein the discrete metal particles are substantially spherical; both the substrate and particles being composed of a Ti6A14V alloy, the substrate having an alpha phase content.

Claim 27

A prosthesis having a porous coating for tissue ingrowth applications on a preselected metallic substrate area, wherein the coating is produced by the following method steps: covering the metallic substrate area of the prosthesis with a blended mixture of primary particles and secondary particles, said primary particles being metallic and capable of metallurgically bonding to the substrate area, said secondary particles being solid phase and capable of mechanically supporting the primary particles in a matrix; raising the temperature of the mixture and metallic substrate area to an elevated temperature at which metallurgical bonding of the primary particles can occur under compression and at which melting of the secondary particles or reactions between the primary and secondary particles does not occur; compressing the mixture against the metallic substrate area while at the elevated temperature to metallurgically bond the contacting primary particles and portions of the substate area as a result of the combination of elevated temperature and compression to which they are subjected; and removing the expendable secondary particles to present a homogenously porous coating on the metallic substrate area in which bonded primary particles are separated from one another by a network of interconnected voids.

Claim 28

A prosthesis having a porous coating for tissue ingrowth applications on a preselected metallic substrate area, wherein the coating is produced by the following method steps: covering the metallic substrate area of the prosthesis with a blended mixture of primary particles and secondary particles, said primary particles being metallic and capable of metallurgically bonding to the substrate area, said secondary particles being solid phase and capable of mechanically supporting the primary particles in a matrix; raising the temperature of the mixture and metallic substrate area to an elevated temperature at which metallurgical bonding of the primary particles can occur under compression and at which melting of the secondary particles or reactions between the primary and secondary particles does not occur; compressing the mixture against the metallic substrate area while at the elevated temperature to metallurgically bond the contacting primary particles and portions of the substate area as a result of the combination of elevated temperature and compression to which they are subjected; and removing the expendable secondary particles to present a homogenously porous coating on the metallic substrate area in which bonded primary particles are separated from one another by a network of interconnected voids.

Claim 29

A prosthesis having a porous coating for tissue ingrowth applications on a preselected metallic substrate area, wherein the coating is produced by the following method steps: positioning the prosthesis within a mold cavity with the metallic substrate area spaced inwardly from the mold cavity surfaces; filling the space between the metallic substrate area and mold cavity surfaces with a blended mixture of primary particles and secondary particles, said primary particles being metallic and capable of metallurgically bonding to the substrate area, said secondary particles being solid phase and capable of mechanically supporting the primary particles in a matrix; heating the prosthesis and mixture of particles to an elevated temperature at which metallurgical bonding can occur between adjacent primary particles and between the primary particles and the metallic substrate area under compression and at which melting of the secondary particles or reactions between the primary and secondary particles does not occur; compressing the mixture of particles against the metallic substrate area while at the elevated temperature to deform the primary particles and the portions of the metallic area engaged thereby and to metallurgically bond the contacting primary particles and portions of the substrate area as a result of the combination of elevated temperature and compression to which they are subjected; and subsequently removing the secondary particles from the resulting matrix of bonded primary particles to present a homogenously porous coating on the metallic substrate area in which bonded primary particles are separated from one another by a network of interconnected voids.

Claim 30

A prosthesis having a porous coating for tissue ingrowth applications on a preselected metallic substrate area, wherein the coating is produced by the following method steps: positioning the prosthesis within a mold cavity with the metallic substrate area spaced inwardly from the mold cavity surfaces; filling the space between the metallic substrate area and mold cavity surfaces with a blended mixture of primary particles and secondary particles, said primary particles being metallic and capable of metallurgically bonding to the substrate area, said secondary particles being solid phase and capable of mechanically supporting the primary particles in a matrix; heating the prosthesis and mixture of particles to an elevated temperature at which metallurgical bonding can occur between adjacent primary particles and between the primary particles and the metallic substrate area under compression and at which melting of the secondary particles or reactions between the primary and secondary particles does not occur; compressing the mixture of particles against the metallic substrate area while at the elevated temperature to deform the primary particles and the portions of the metallic area engaged thereby and to metallurgically bond the contacting primary particles and portions of the substrate area as a result of the combination of elevated temperature and compression to which they are subjected; and subsequently removing the secondary particles from the resulting matrix of bonded primary particles to present a homogenously porous coating on the metallic substrate area in which bonded primary particles are separated from one another by a network of interconnected voids.

Claim 31

The prosthesis of claim 24 wherein the metallic substrate area of the prosthesis and the primary particles are each composed of Ti6A14V alloy; said elevated temperature being below the beta transus temperature for the alloy.