Systems and Methods Implementing Layers of Devitrified Metallic Glass-Based Materials

Abstract

Systems and methods in accordance with embodiments of the invention implement layers of devitrified metallic glass-based materials. In one embodiment, a method of fabricating a layer of devitrified metallic glass includes: applying a coating layer of liquid phase metallic glass to an object, the coating layer being applied in a sufficient quantity such that the surface tension of the liquid phase metallic glass causes the coating layer to have a smooth surface; where the metallic glass has a critical cooling rate less than 10 6 K/s; and cooling the coating layer of liquid phase metallic glass to form a layer of solid phase devitrified metallic glass.

What claimed is: 
     
         1 . A method of fabricating a layer of devitrified metallic glass comprising:
 providing a liquid phase metallic glass having a critical cooling rate of less than 10 6  K/s;   applying a liquid phase metallic glass to an object, wherein applying the coating layer comprises immersing at least a portion of the object such that the object is wetted by the liquid phase metallic glass to form a layer of liquid phase metallic glass on the outer surface thereof; and   solidifying the layer of liquid phase metallic glass-forming alloy such that a solid phase devitrified metallic glass-forming coating is formed therefrom.   
     
     
         2 . The method of  claim 1  where the grain size of the coating is nanocrystalline with an average grain size from 10 nanometers to 1000 nanometers. 
     
     
         3 . The method of  claim 2  where the grain size is greater than 1 micrometer. 
     
     
         4 . The method of  claim 1  where the coating crystallizes during cooling from the liquid phase. 
     
     
         5 . The method of  claim 1  further comprising applying an external heat source to heat the object during solidifying. 
     
     
         6 . The method of  claim 1  further comprising:
 quenching the liquid phase at a cooling rate faster than the critical cooling rate of the liquid phase metallic glass to form a solid phase metallic glass coating; 
 heating the solid phase metallic glass coating to a processing temperature above the glass transition temperature of the metallic glass and holding the metallic glass coating at the processing temperature to form a devitrified metallic glass-forming coating; and 
 cooling the devitrified metallic glass-forming coating to below the glass transition temperature. 
 
     
     
         7 . The method of  claim 1  where the devitrified coating has a hardness that is at least 10% higher than the amorphous phase of the same alloy. 
     
     
         8 . The method of  claim 1  where the devitrified coating has a Young's modulus that is at least 10% higher than the amorphous phase of the same alloy. 
     
     
         9 . The method of  claim 1  where the metallic glass-forming alloy is applied to an object that is at a higher temperature than the liquidus temperature of the metallic glass-form ing alloy causing it to melt and wet the object. 
     
     
         10 . The method of  claim 1  where the devitrified coating has a lower surface roughness than the object to which the liquid phase metallic glass is applied. 
     
     
         11 . The method of  claim 1  where the immersion of the object comprises one of the methods selected from the group consisting of dipping, pouring and spraying. 
     
     
         12 . The method of  claim 1  where the object being coated is made from metal, polymer, ceramic, glass, or mixtures thereof. 
     
     
         13 . The method of  claim 1 , wherein the thickness of the coating layer is greater than 50 micrometers. 
     
     
         14 . The method of  claim 1 , wherein the thickness of the coating layer is greater than 1 mm. 
     
     
         15 . The method of  claim 1  where the coating process is done under a vacuum or inert environment. 
     
     
         16 . The method of  claim 1  where the coating does not exhibit a glass transition temperature when heated. 
     
     
         17 . The method of  claim 1  further comprising spinning the object during the applying and solidifying. 
     
     
         18 . The method of  claim 1 , wherein the object comprises one of aluminum, titanium, steel, cobalt, graphite, quartz, silicon carbide, and mixtures thereof. 
     
     
         19 . The method of  claim 1 , wherein the metallic glass has a melting temperature of less than 800° C. 
     
     
         20 . A method of fabricating a layer of devitrified metallic glass comprising:
 providing a liquid phase metallic glass having a critical cooling rate of less than 10 6  K/s and a melting temperature of less than 800° C.;   applying a liquid phase metallic glass to an object, wherein applying the coating layer comprises immersing at least a portion of the object such that the object is wetted by the liquid phase metallic glass to form a layer of liquid phase metallic glass on the outer surface thereof; and   solidifying the layer of liquid phase metallic glass-forming alloy such that a solid phase devitrified metallic glass-forming coating is formed therefrom.