Thixotropic processing of magnesium composites with a nanoparticles-haloed grain structure for biomedical implant applications

Patent metadata

Field	Value
Publication number	US-10532134-B2
Application number	US-201314391179-A
Country	US
Kind code	B2
Filing date	Apr 18, 2013
Priority date	Apr 18, 2012
Publication date	Jan 14, 2020
Grant date	Jan 14, 2020

Abstract

In described embodiments, the present invention includes a magnesium-based composite material formed from a plurality of α-phase magnesium grains; and a β-alloy phase comprising magnesium and nano-diamond and/or and phosphate containing nanoparticles, the β-alloy phase surrounding each of the plurality of magnesium grains. A method of manufacturing a composite material is also disclosed.

First claim

We claim:

1. A magnesium-based composite medical implant comprising:
a crystalline structure of α-phase magnesium grains; and a β-alloy phase comprising magnesium and a combination of functionalized nano-diamond particles and calcium phosphate nanoparticles, wherein the β-alloy phase forms a halo around each of the α-phase magnesium grains.

2. The composite medical implant according to claim 1 , wherein the functionalized nano-diamond comprises a functional group selected from the group consisting of hydroxyl group, a carboxyl group, a carbonyl group, and a combination thereof.

3. The composite medical implant according to claim 1 , wherein each of the functionalized nano-diamonds has a size range between about 2 nm and less than 5 nm.

4. The composite medical implant according to claim 1 , wherein each of the nano-phosphate particles has a size range between about 20 nm and about 300 nm.

5. The composite medical implant according to claim 1 , wherein the β-alloy phase comprises about 5% by weight of nanodiamonds.

6. A magnesium-based composite medical implant formed by a process comprising the steps of:
providing magnesium in a thixotropic mixer;
heating the magnesium above the magnesium α-phase temperature, thereby obtaining a fully molten liquid;
lowering the temperature of the fully molten liquid below the magnesium α-phase temperature, but above the magnesium β-alloy phase temperature to form a melt;
mixing the melt to obtain a slurry comprising solid α-phase magnesium grains suspended in a magnesium β-alloy phase;
adding functionalized diamond and calcium phosphate nanoparticles to the slurry; and
mixing the nanoparticle-added slurry in a mixer to form a mixture; and
discharging the mixture from the mixer,
wherein the β-alloy phase forms a halo around each of the α-phase magnesium grains wherein the α-phase magnesium grains are formed in a crystalline structure.

7. A magnesium-based composite medical implant comprising:
a crystalline structure of α-phase magnesium grains; and a β-alloy phase consisting essentially of magnesium and a combination of functionalized nano-diamond particles and calcium phosphate nanoparticles, wherein the β-alloy phase forms a halo around each of the α-phase magnesium grains.

Assignees

• Univ Drexel
• Georgia Institute Of Tech

Inventors

• Zhou Gongyao
• Gong Haibo
• Yao Donggang

Classifications

• A61L2400/12

  Nanosized materials, e.g. nanofibres, nanoparticles, nanowires, nanotubes; Nanostructured surfaces · CPC title

• C22C1/00

  Making non-ferrous alloys (by electrothermic methods C22B4/00; by electrolysis C25C1/24, C25C3/36) · CPC title

• A61L27/427

  of other specific inorganic materials not covered by A61L27/422 or A61L27/425 · CPC title

• A61L27/425

  of phosphorus containing material, e.g. apatite · CPC title

• C22C23/02

  with aluminium as the next major constituent · CPC title