NANOPARTICLE-STABILIZED IMMISCIBLE ALLOYS

• US 20180320252A1
• Filed: 06/27/2018
• Published: 11/08/2018
• Est. Priority Date: 11/06/2012
• Status: Active Grant

• Current Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Original Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Inventors: Li, Xiaochun, Chen, Lianyi, Xu, Jiaquan
• Granted Patent: US 10,640,850 B2
• Time in Patent Office: Days
• CPC Class Codes: B22F 1/16 Metallic particles coated with a non-metal coated with lubricating or binding agents or with organic material B22F1/10
• CPC Class Codes: B32B 15/016 all layers being formed of aluminium or aluminium alloys
• CPC Class Codes: C22C 1/02 by melting C22C1/1036 takes precedence
• CPC Class Codes: C22C 1/026 Alloys based on aluminium
• CPC Class Codes: C22C 1/06 with the use of special agents for refining or deoxidising
• CPC Class Codes: C22C 1/1036 starting from a melt
• CPC Class Codes: C22C 1/1047 by mixing and casting liquid metal matrix composites
• CPC Class Codes: C22C 21/00 Alloys based on aluminium
• CPC Class Codes: C22C 21/003 containing at least 2.6% of one or more of the elements: tin, lead, antimony, bismuth, cadmium, and titanium
• CPC Class Codes: C22C 32/0047 with carbides, nitrides, borides or silicides as the main non-metallic constituents

Abstract

Solid immiscible alloys and methods for making the solid immiscible alloys are provided. The microstructure of the immiscible alloys is characterized by a minority phase comprising a plurality of particles of an inorganic material dispersed in a majority phase comprising a continuous matrix of another inorganic material. The methods utilize nanoparticles to control both the collisional growth and the diffusional growth of the minority phase particles in the matrix during the formation of the alloy microstructure.

Claims

1. A method of making a solid immiscible alloy material comprising:

an immiscible alloy having a majority phase comprising a continuous matrix of a first inorganic material and a minority phase comprising a plurality of particles of a second inorganic material dispersed in the majority phase; and

nanoparticles comprising a thermally stable material coating the surfaces of the dispersed minority phase particles;

the method comprising;

(a) forming a single-phase liquid solution comprising the first inorganic material and the second inorganic material at a temperature above the liquid miscibility gap for the immiscible alloy;

(b) introducing solid nanoparticles comprising a thermally stable material into the single-phase liquid solution while it is at a temperature above the liquid miscibility gap;

(c) cooling the liquid solution through the liquid miscibility gap, whereby the nanoparticles form a coating on liquid droplets of the minority phase that forms in a liquid matrix of the majority phase; and

(d) cooling the resulting material to a temperature below the solidus temperature, whereby the solid immiscible alloy material forms.

2. The method of claim 1, wherein the step of cooling the liquid solution through the liquid miscibility gap is carried out at a cooling rate of no greater than about 500 K/s.

3. The method of claim 1, wherein the minority phase particles have an average diameter of no greater than about 20 μ

m and the average smallest diameter for the distribution of the thermally stable nanoparticles is no greater than about 250 nm.

4. The method of claim 1, wherein the first inorganic material is a metal, the second inorganic material is a metal or metalloid and the thermally stable material is a ceramic.

5. The method of claim 3, wherein the nanoparticles account for about 0.1 to about 5 vol. % of the solid immiscible alloy.

6. The method of claim 4, wherein the immiscible alloy is an aluminum-based alloy.