Powder Metal Composition With Aluminum Nitride MMC

Abstract

A powder metal composition comprising an aluminum (Al) powder metal, an aluminum-copper (Al—Cu) powder metal, a magnesium (Mg) powder metal, a tin (Sn) powder metal, an aluminum-silicon (Al—Si) powder metal, and aluminum nitride (AlN) as a metal-matrix composite additive. In at least some forms, the aluminum (Al) powder metal includes a portion which is fine aluminum powder metal. This powder metal composition is compressible to form a green powder metal compact which may be sintered to form a sintered part which has a composition and properties approximating that of a 6061 aluminum alloy product.

What is claimed is: 
     
         1 . A powder metal composition comprising:
 aluminum (Al) powder metal;   aluminum-copper (Al—Cu) powder metal;   magnesium (Mg) powder metal;   tin (Sn) powder metal;   aluminum-silicon (Al—Si) powder metal; and   aluminum nitride (AlN) as a metal-matrix composite additive.   
     
     
         2 . The powder metal composition of  claim 1 , wherein at least a portion of the aluminum (Al) powder metal is a fine aluminum powder metal. 
     
     
         3 . The powder metal composition of  claim 2 , wherein the portion of the aluminum (Al) powder metal that is the fine aluminum powder metal is 10 wt % of the aluminum (Al) powder metal. 
     
     
         4 . The powder metal composition of  claim 2 , wherein the portion of the aluminum (Al) powder metal that is the fine aluminum powder metal is in a range of 5 to 30 wt % of the aluminum (Al) powder metal. 
     
     
         5 . The powder metal composition of  claim 1 :
 wherein a total aluminum content provided by the aluminum (Al) power metal, the aluminum-copper (Al—Cu) powder metal, and the aluminum-silicon (Al—Si) powder metal is 95.2 wt % of the powder metal composition;   wherein the total copper content provided by the aluminum-copper (Al—Cu) powder metal is 0.29 wt %;   wherein the total magnesium content provided by the magnesium (Mg) powder metal is 1.07 wt %;   wherein the total tin content provided by the tin (Sn) powder metal is 0.49 wt %;   wherein the total silicon content provided by the aluminum-silicon (Al—Si) powder metal is 0.49 wt %;   wherein the aluminum nitride (AlN) is 0.98% wt%;   wherein the powder metal composition further includes a flow aid and the flow aid is 0.02 wt %; and   wherein the powder metal composition further includes a lubricant and the lubricant is 1.46 wt %.   
     
     
         6 . The powder metal composition of  claim 1 :
 wherein the aluminum (Al) powder metal is a majority of +60/−250 mesh powder and a portion of the aluminum (Al) powder metal is fine aluminum powder metal;   wherein the aluminum-copper (Al—Cu) powder metal is a −325 mesh;   wherein the magnesium (Mg) powder metal is a −200 mesh;   wherein the tin (Sn) powder metal is a −325 mesh; and   wherein the aluminum-silicon (Al—Si) powder metal is −325 mesh.   
     
     
         7 . The powder metal composition of  claim 1 , wherein the aluminum-copper (Al—Cu) powder metal is a 50Al-50Cu powder metal. 
     
     
         8 . The powder metal composition of  claim 7 , wherein the 50Al-50Cu powder metal is atomized and crushed. 
     
     
         9 . The powder metal composition of  claim 1 , wherein the aluminum-silicon (Al—Si) powder metal is an 88Al-12Si powder metal. 
     
     
         10 . The powder metal composition of  claim 1 , wherein the powder metal composition further includes a lubricant. 
     
     
         11 . The powder metal composition of  claim 1 , wherein the powder metal composition further includes a flow aid. 
     
     
         12 . The powder metal composition of  claim 11 , wherein the flow aid is fumed SiO 2 . 
     
     
         13 . The powder metal composition of  claim 1 , wherein the powder metal composition has even distribution of the various powders. 
     
     
         14 . The powder metal composition of  claim 1 , wherein the aluminum nitride (AlN) has a specific surface area of less than or equal to 2.0 m 2 /g and has a particle size distribution of D 10% of between 0.4 and 1.4 μm, D 50% of between 6 and 10 μm, and D 90% of between 17 and 35 μm. 
     
     
         15 . The powder metal composition of  claim 1 , wherein the aluminum nitride (AlN) has a specific surface area of between 1.8 and 3.8 m 2 /g and has a particle size distribution of D 10% of between 0.2 and 0.6 μm, D 50% of between 1 and 3 μm, and D 90% of between 5 and 10 μm. 
     
     
         16 . The powder metal composition of  claim 1 , wherein the aluminum nitride (AlN) has a hexagonal crystal structure and is single phase. 
     
     
         17 . The powder metal composition of  claim 1 , wherein the powder metal composition has a flow rate of between 2.8 and 3.0 g/s. 
     
     
         18 . The powder metal composition of  claim 1 , wherein the powder metal composition has an apparent density of 1.21 g/cc. 
     
     
         19 . A green compact formed from the powder metal composition of  claim 1 . 
     
     
         20 . A sintered powder metal component formed from a green compact of  claim 19 .