Method of making powder metal parts using shock loading

Abstract

A method of preparing a titanium-based metal matrix composite component. The method includes combining a titanium alloy-based matrix and a titanium-based ceramic reinforcement to form one or more mixtures, placing the mixture or mixtures into a mold, compacting the mixture or mixtures by shock loading, and sintering the compacted mixture or mixtures. In one form, the various mixtures may include differing levels of reinforcement concentration. In this way, different portions of a component produced by the present method may be made up of different mixtures from other portions of the manufactured component, thereby facilitating tailored mechanical or related structural properties.

1 . A method of making a titanium-based metal matrix composite component, said method comprising:
 combining a titanium alloy-based matrix and a titanium-based ceramic reinforcement to form at least one mixture;   placing said at least one mixture into a mold;   compacting said at least one mixture by shock loading; and   sintering said compacted at least one mixture.   
     
     
         2 . The method of  claim 1 , wherein said titanium alloy-based matrix substantially comprises Ti-6Al-4V and said ceramic reinforcement substantially comprises TiB 2 . 
     
     
         3 . The method of  claim 1 , wherein said component is an automotive component. 
     
     
         4 . The method of  claim 3 , wherein said automotive component is an engine component. 
     
     
         5 . The method of  claim 4 , wherein said engine component is a connecting rod. 
     
     
         6 . The method of  claim 1 , wherein said at least one mixture comprises at least a first mixture comprising a first concentration of said titanium-based ceramic reinforcement, and a second mixture comprising a second concentration of said titanium-based ceramic reinforcement that is different from said first mixture. 
     
     
         7 . The method of  claim 6 , wherein said placing said at least one mixture into a mold comprises:
 selectively placing one of said first and second mixtures into a first region within said mold; and   selectively placing the other of said first and second mixtures into a second region within said mold such that upon said compacting, the portion of said component corresponding to said first region substantially comprises one of said first and second mixtures, while the portion of said component corresponding to said second region substantially comprises the other of said first and second mixtures.   
     
     
         8 . The method of  claim 1 , wherein a source of said shock loading is selected from the group consisting of compressed spring, electrohydraulic, electromagnetic, piezoelectric and explosive means. 
     
     
         9 . The method of  claim 8 , wherein said explosive means is selected from the group consisting of explosive shock loading and electric gun shock loading. 
     
     
         10 . The method of  claim 1 , further comprising performing post-sintering machining on said component. 
     
     
         11 . A method of making a titanium-based metal matrix composite component, said method comprising:
 defining a plurality of regions within a mold that is substantially shaped in the form of said component;   arranging a plurality of mixtures comprising a titanium alloy-based matrix and a titanium-based ceramic reinforcement, each of said plurality of mixtures configured to comprise a different matrix-to-reinforcement ratio than the others;   placing a first of said plurality of mixtures into a first of said plurality of regions;   placing a second of said plurality of mixtures into a second of said plurality of regions;   compacting said plurality of mixtures in said mold by shock loading such that upon said compacting, the portion of said component corresponding to said first region substantially comprises said first mixture, while the portion of said component corresponding to said second region substantially comprises said second mixture;   removing said component from said mold; and   sintering said component.   
     
     
         12 . The method of  claim 11 , wherein said matrix is selected from the group consisting of beta titanium, alpha-2 titanium, gamma titanium and combinations thereof, and said reinforcement comprises a ceramic. 
     
     
         13 . The method of  claim 12 , wherein said ceramic comprises TiB 2 . 
     
     
         14 . The method of  claim 11 , further comprising performing post-sintering operations on said component. 
     
     
         15 . The method of  claim 14 , wherein said post-sintering operations comprise machining. 
     
     
         16 . The method of  claim 11 , wherein said component comprises a connecting rod, further wherein said first of said plurality of mixtures contains a lower concentration of reinforcing phase than said second mixture and the portion of said connecting rod that said first of said plurality of mixtures is placed in has a lower requirement of at least one of strength and stiffness than the portion of said connecting rod that said second of said plurality of mixtures is placed in. 
     
     
         17 . A method of making a titanium-based metal matrix composite connection rod for an internal combustion engine, said method comprising:
 combining a titanium alloy-based matrix and a titanium-based ceramic reinforcement into a plurality of mixtures such that each of said plurality of mixtures comprises a different matrix-to-reinforcement ratio than the others;   placing a first of said plurality of mixtures into a first region of a connecting rod mold;   placing a second of said plurality of mixtures into a second region of said connecting rod mold;   compacting said plurality of mixtures in said connecting rod mold by shock loading;   removing said connecting rod from said mold; and   sintering said compacted plurality of mixtures.   
     
     
         18 . The method of  claim 17 , wherein said connecting rod substantially comprises a Ti-6Al-4V/TiB 2  metal matrix composite. 
     
     
         19 . The method of  claim 17 , wherein said shock loading is accomplished through movement of a compaction member in response to a shock source selected from the group consisting of a compressed spring, an electrohydraulic device, an electromagnetic device, a piezoelectric device, an explosive device and an electric gun. 
     
     
         20 . The method of  claim 17 , wherein said compacting takes place in less than one second.