Systems and methods for forming a layer onto a surface of a solid substrate and products formed thereby

Abstract

A method for forming a vehicular brake rotor involving loading a shaped metal substrate with a mixture of metal alloying components and ceramic particles in a dieheating the contents of the die while applying pressure to melt at least one of the metal components of the alloying mixture whereby to densify the contents of the die and form a ceramic particle-containing metal matrix composite coating on the metallic substrate; and cooling the resulting coated product.

What is claimed is: 
     
         1 . A method for integrating a liquid metal matrix composite to a surface of a metal substrate, the method comprising:
 enabling a reaction involving the liquid metal matrix composite; and   heating and densifying the combination of the liquid metal matrix composite and the metal substrate during at least a portion of the reaction, and cooling the metal matrix composite from liquid to solid while applying pressure to the composite, and optionally heat treating the formed product.   
     
     
         2 . The method of  claim 1 , further comprising densifying the combination of the liquid metal matrix composite and the metal substrate during at least a portion of a duration of the reaction. 
     
     
         3 . The method of  claim 1 , wherein the volume of the liquid metal matrix composite is less than the volume of the substrate. 
     
     
         4 . The method of  claim 1 , wherein the substrate has a melting temperature that corresponds to the melting point of an element of the group consisting of aluminum, iron and titanium, or an alloy thereof, preferably an aluminum alloy comprises aluminum and one or more elements of the group consisting of cobalt, copper, iron. nickel, titanium, vanadium, zinc, chromium, magnesium, manganese, niobium, and silicon 
     
     
         5 . The method of  claim 1 , characterized by one or more of the following features:
 a. wherein the reaction involves an exothermic reaction of two or more metals selected from the group consisting of aluminum, boron, cobalt, copper, iron. nickel, palladium, titanium, vanadium, zinc, chromium, magnesium, manganese, niobium, and silicon;   b. wherein the reaction involves a first reactant of the liquid metal matrix of the composite and a second reactant of the liquid metal matrix of the composite; and   c. wherein the liquid metal matrix composite comprises an aluminum alloy and a ceramic particulate, preferably silicon carbide.   
     
     
         6 . The method of  claim 1 , wherein:
 a. the substrate comprises a metal selected from the group consisting of aluminum, iron and titanium; and   b. the metal matrix composite comprises silicon carbide, and an alloy of aluminum and silicon, or an alloy of aluminum, silicon, and magnesium, or an alloy of aluminum and titanium, or an alloy of aluminum, silicon and titanium, or a prealloyed powder selected from Ti—Al or Ti—Al—Cr—Nb.   
     
     
         7 . The method of  claim 1 , wherein from 25% to 65% of an exterior surface of the layer, preferably 35% or more of an exterior surface of the layer, comprises ceramic particulate. 
     
     
         8 . The method of  claim 1 , wherein a porosity of the formed product is less than 2% by volume, preferably less than 1% by volume, more preferably less than 0.25% by volume. 
     
     
         9 . The method of  claim 1 , further comprising enabling the reaction in less than ambient atmospheric pressure. 
     
     
         10 . The method of  claim 1 , wherein the substrate comprises a hub-disc assembly for a vehicle brake. 
     
     
         11 . A method for integrating a metal matrix composite to a surface of a metal substrate, the method comprising:
 enabling a reaction involving the metal matrix composite; and   heating and densifying the combination of the metal matrix composite and the metal substrate during at least a portion of the reaction, and cooling the metal matrix composite and metal substrate while applying pressure to the composite, and optionally heat treating the formed product.   
     
     
         12 . The method of  claim 11 , further comprising densifying the combination of the metal matrix composite and the metal substrate during at least a portion of a duration of the reaction. 
     
     
         13 . The method of  claim 11 , wherein the volume of the metal matrix composite is less than the volume of the substrate. 
     
     
         14 . The method of  claim 11 , wherein the substrate has a melting temperature that corresponds to the melting point of an element of the group consisting of aluminum, iron and titanium, or an alloy thereof, preferably an aluminum alloy comprises aluminum and one or more elements of the group consisting of cobalt, copper, iron. nickel, titanium, vanadium, zinc, chromium, magnesium, manganese, niobium, and silicon 
     
     
         15 . The method of  claim 11 , characterized by one or more of the following features:
 a. wherein the reaction involves an exothermic reaction of two or more metals selected from the group consisting of aluminum, boron, cobalt, copper, iron. nickel, palladium, titanium, vanadium, zinc, chromium, magnesium, manganese, niobium, and silicon;   b. wherein the reaction involves a first reactant of the metal matrix of the composite and a second reactant of the metal matrix of the composite; and   c. wherein the metal matrix composite comprises an aluminum alloy and a ceramic particulate, preferably silicon carbide.   
     
     
         16 . The method of  claim 11 , wherein:
 a. the substrate comprises a metal selected from the group consisting of aluminum, iron and titanium; and   b. the metal matrix composite comprises silicon carbide, and an alloy of aluminum and silicon, or an alloy of aluminum, silicon, and magnesium, or an alloy of aluminum and titanium, or an alloy of aluminum, silicon and titanium, or a prealloyed powder selected from Ti—Al or Ti—Al—Cr—Nb.   
     
     
         17 . The method of  claim 11 , wherein from 25% to 65% of an exterior surface of the layer, preferably 35% or more of an exterior surface of the layer, comprises ceramic particulate. 
     
     
         18 . The method of  claim 11 , wherein a porosity of the formed product is less than 2% by volume, preferably less than 1% by volume, more preferably less than 0.25% by volume. 
     
     
         19 . The method of  claim 11 , further comprising enabling the reaction in less than ambient atmospheric pressure. 
     
     
         20 . The method of  claim 11 , wherein the substrate comprises a hub-disc assembly for a vehicle brake.