Ultrahigh ductility, novel Mg—Li based alloys for biomedical applications

Patent metadata

Field	Value
Publication number	US-11896735-B2
Application number	US-202117381445-A
Country	US
Kind code	B2
Filing date	Jul 21, 2021
Priority date	Dec 12, 2014
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

The invention includes compositions including magnesium-lithium alloys containing various alloying elements for medical implant devices. The devices are constructed of the compositions or have applied thereto a coating formed therefrom. Within the structure of the magnesium-lithium alloy, there is a co-existence of alpha and beta phases. The invention also includes methods of preparing the magnesium-lithium alloys and articles, such as medical implant devices, for use in medical applications, including orthopedic, dental, craniofacial and cardiovascular surgery.

First claim

The invention claimed is:

1. A method for preparing a medical implant device, comprising: fabricating a substrate structured for implanting into a body, comprising: forming an alloy, comprising:
I melting 9.00% by weight of lithium, 0.96% by weight of zinc, and 0.01% by weight of aluminum, and a remainder of magnesium based on the total weight of the alloy, or
II melting about 8.99% by weight of lithium, 0.87% by weight of zinc, 1.07% by weight of aluminum, and a remainder of magnesium based on the total weight of the alloy, or
III melting about 6.11% by weight of lithium, 0.92% by weight of zinc, 0.04% by weight of aluminum, and a remainder of magnesium based on the total weight of the alloy,
wherein the alloy of I, II, or III is structured to exhibit a co-existence of alpha and beta phases,
wherein the alloy of I, II, or III exhibits one or more of improved ductility and elasticity;
casting the alloy of I, II, or III to form a casted alloy; and
extruding the casted alloy to form the substrate in an extruded form.

2. The method of claim 1 , wherein the melting step of I, II, or III further comprises one or more alloying elements selected from the group consisting of iron, zirconium, manganese, calcium, yttrium, rare earth elements, strontium, copper, silver, silicon, sodium, potassium and cerium.

3. The method of claim 1 , further comprising adding an active agent to the alloy of I, II, or III.

4. The method of claim 1 , further comprising using the medical implant device in orthopedic, dental, craniofacial and cardiovascular surgeries.

5. The method of claim 1 , wherein the medical implant device releases lithium ions as a therapeutic drug eluting device.

6. A method for preparing a medical implant device, comprising:
fabricating a substrate structured for implanting into a body, comprising:
forming an alloy, comprising:
melting from about 5% by weight to about 11% by weight of lithium and a remainder of magnesium based on the total weight of the alloy, comprising:
high energy mechanical alloying of the lithium and the magnesium;
followed by uniaxial or isostatic compaction; and
followed by sintering,

wherein the alloy is structured to exhibit a co-existence of alpha and beta phases, and
wherein the alloy exhibits one or more of improved ductility and elasticity;
casting the alloy to form a casted alloy; and
extruding the casted alloy to form the substrate in an extruded form.

7. The method of claim 1 , wherein the melting step of I, II, or III comprises: high energy mechanical alloying of the lithium, the zinc, the aluminum, and the magnesium; followed by uniaxial or isostatic compaction; and followed by sintering.

Assignees

• Univ Of Pittsburgh—Of The Commonwealth System Of Higher Education

Inventors

• Kumta Prashant N
• Wu Jingyao
• Velikokhatnyi Oleg

Classifications

• A61L27/30 Primary

  Inorganic materials · CPC title

• A61L27/047 Primary

  Other specific metals or alloys not covered by A61L27/042 - A61L27/045 or A61L27/06 · CPC title

• A61L27/306

  Other specific inorganic materials not covered by A61L27/303 - A61L27/32 · CPC title

• A61L27/54

  Biologically active materials, e.g. therapeutic substances {(A61L27/227 takes precedence)} · CPC title

• A61L31/022

  Metals or alloys · CPC title