Method of forming articles from alloys of tin and/or titanium

Abstract

The invention relates to a method of forming an article from an alloy, such as a tin-containing alloy or titanium-containing alloy. Elemental metal powders of metal constituents of the alloy are injected into a pre-heated die and pressure is applied to form a green part. The green part is then alloyed at a predetermined temperature for a pre-determined time period to form the article. The invention also relates to an article formed by such a method.

1 . A method of forming an article from a tin-containing alloy, the method comprising the steps of: 
 (a) injecting elemental metal powders of metal constituents of the alloy into a preheated die at a temperature of above about 240° C.;    (b) applying a predetermined pressure to the elemental powders for a predetermined time period to produce a green part; and    (c) alloying the green part at a predetermined temperature for a predetermined time period to form said article;    wherein said elemental metal powders include Sn powder in an amount of at least 2 wt % based on the total weight of the elemental metal powders.    
     
     
         2 . A method according to  claim 1 , wherein said elemental metal powders include at least Ti and Sn powders.  
     
     
         3 . A method according to  claim 1 , wherein said elemental metal powders include at least Ti, Sn and Al powders.  
     
     
         4 . A method according to  claim 1 , wherein said elemental metal powders include Sn powder in an amount of from 2-12 wt % based on the total weight of the elemental metal powders.  
     
     
         5 . A method according to  claim 1 , wherein pressurising step (b) includes applying a pressure of from 1000 to 2800 psi for a time period of from 0.5 to 3 minutes.  
     
     
         6 . A method according to  claim 1 , wherein alloying step (c) includes alloying the green part at a temperature of from 1250 to 1350° C. for a time period of from 30 to 150 minutes.  
     
     
         7 . A method of forming an article from a titanium-containing alloy, the method comprising the steps of: 
 (a) injecting elemental metal powders of metal constituents of the alloy into a preheated die at a predetermined temperature, the temperature being determined based on the constituents of the alloy;    (b) applying a predetermined pressure to the elemental powders for a predetermined time period to produce a green part; and    (c) alloying the green part at a predetermined temperature for a predetermined time period to form said article;    wherein said predetermined temperature of injecting step (a) is greater than about 100° C. if said elemental metal powders include Sn powder, and is greater than about 350° C. if said elemental metal powders include Al powder.    
     
     
         8 . A method according to  claim 7 , wherein said elemental metal powders include Ti and Al powders and said predetermined temperature of injecting step (a) is between 450 and 550° C.  
     
     
         9 . A method according to  claim 8 , wherein the predetermined pressure in the pressurising step (b) is from 2000 to 3000 psi and the predetermined time period in step (b) is from 120 to 480 minutes.  
     
     
         10 . A method of forming an article from an alloy, the method comprising the steps of: (a) introducing elemental metal powders of metal constituents of the alloy into a die and applying a pressure of from 2000 to 3000 psi for a time period of from 1 to 5 minutes to form a preform; (b) applying a predetermined pressure and temperature to the preform for a predetermined time period to produce a green part; and (c) alloying the green part at a predetermined temperature for a predetermined time period to form said article.  
     
     
         11 . An article formed by the method of  claim 1 .  
     
     
         12 . An article formed by the method of  claim 2 .  
     
     
         13 . An article formed by the method of  claim 3 .  
     
     
         14 . An article formed by the method of  claim 4 .  
     
     
         15 . An article formed by the method of  claim 5 .  
     
     
         16 . An article formed by the method of  claim 6 .  
     
     
         17 . An article formed by the method of  claim 7 .  
     
     
         18 . An article formed by the method of  claim 8 .  
     
     
         19 . An article formed by the method of  claim 9 .  
     
     
         20 . An article formed by the method of  claim 10.