Powder Metallurgy Counterpart to Wrought Aluminum Alloy 6063

Abstract

A powder metal composition for a powder metal material to be compacted, sintered, and heat treated is comparable to wrought 6063 aluminum alloy. The powder metal composition consists essentially of an aluminum powder metal with no pre-alloyed alloying additions, an aluminum-silicon powder metal, an elemental magnesium powder metal, optionally an elemental tin powder metal, and optionally a ceramic addition (which is not included when calculating the weight percentages of the alloying elements). A weight percent of silicon is in a range of 0.2 to 0.6 wt % of the powder metal composition, of magnesium is in a range of 0.5 to 0.9 wt %, and of tin is in a range of 0.0 to 1.0 wt %. This powder metal is compactable to form a green compact which is further sinterable and heat treatable to provide a powder metal composition comparable to a wrought 6063 aluminum alloy and which offers exceptional thermal conductivity.

What is claimed is: 
     
         1 . A powder metal composition providing a powder metal material to be compacted, sintered, and heat treated to be comparable to wrought 6063 aluminum alloy, the powder metal composition consisting essentially of:
 an aluminum powder metal with no pre-alloyed alloying additions apart from any inevitable non-effective trace amounts;   an aluminum-silicon powder metal;   an elemental magnesium powder metal;   optionally an elemental tin powder metal;   optionally a ceramic powder addition to provide a metal matrix composite upon sintering, which ceramic powder addition is not taken into account when calculating alloying percentages of the powder metal composition; and   a lubricant wherein the weight percentages of the alloying elements are exclusive of the weight of the lubricant as the lubricant is configured to be burned off during sintering of the powder metal composition;   wherein a weight percent of silicon in the powder metal composition is in a range of 0.2 to 0.6 wt % of the powder metal composition, a weight percent of magnesium in the powder metal composition is in a range of 0.5 to 0.9 wt % of the powder metal composition, and a weight percent of tin in the powder metal composition is in a range of 0.0 to 1.0 wt % of the powder metal composition.   
     
     
         2 . The powder metal composition of  claim 1 , wherein:
 the weight percent of silicon in the powder metal composition is more narrowly in a range of 0.3 to 0.5 wt % of the powder metal composition; and   the weight percent of magnesium in the powder metal composition is more narrowly in a range of 0.6 to 0.8 wt % of the powder metal composition.   
     
     
         3 . The powder metal composition of  claim 2 , wherein:
 the weight percent of silicon in the powder metal composition is more narrowly in a range of 0.35 to 0.45 wt % of the powder metal composition; and   the weight percent of magnesium in the powder metal composition is more narrowly in a range of 0.65 to 0.75 wt % of the powder metal composition.   
     
     
         4 . The powder metal composition of  claim 2 , wherein:
 the weight percent of silicon in the powder metal composition is 0.4 wt % of the powder metal composition; and   the weight percent of magnesium in the powder metal composition is 0.7 wt % of the powder metal composition.   
     
     
         5 . The powder metal composition of  claim 1 , wherein the aluminum powder metal is at least 99.7% by weight aluminum. 
     
     
         6 . The powder metal composition of  claim 1 , wherein the aluminum-silicon powder metal is an Al-12Si master alloy powder metal having 88 wt % aluminum and 12 wt % silicon. 
     
     
         7 . The powder metal composition of  claim 1 , wherein the weight percent of tin in the powder metal composition is more narrowly in a range of 0.25 to 0.75 wt % of the powder metal composition. 
     
     
         8 . The powder metal composition of  claim 7 , wherein the weight percent of tin in the powder metal composition is 0.5 wt % of the powder metal composition. 
     
     
         9 . The powder metal composition of  claim 1 , wherein the ceramic powder addition is less than 15 volume percent of the powder metal. 
     
     
         10 . The powder metal composition of  claim 9  wherein the ceramic powder addition is an aluminum nitride. 
     
     
         11 . The powder metal composition of  claim 10 , wherein the aluminum nitride 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 μm and 1.4 μm, D 50% of between 6 μm and 10 μm, and D 90% of between 17 μm and 35 μm. 
     
     
         12 . The powder metal composition of  claim 10 , wherein the aluminum nitride has a specific surface area of between 1.8 m 2 /g and 3.8 m 2 /g and has a particle size distribution of D 10% of between 0.2 μm and 0.6 μm, D 50% of between 1 μm and 3 μm, and D 90% of between 5 μm and 10 μm. 
     
     
         13 . The powder metal composition of  claim 10 , wherein the aluminum nitride (AlN) has a hexagonal crystal structure and is single phase. 
     
     
         14 . The powder metal composition of  claim 10 , wherein the ceramic powder addition is silicon carbide (Sic). 
     
     
         15 . A green compact formed from the powder metal composition of  claim 1 . 
     
     
         16 . A sintered powder metal component formed from the green compact of  claim 15 . 
     
     
         17 . The sintered powder metal part of  claim 16 , wherein the powder metal part has a thermal conductivity of between 190 W/m*K and 205 W/m*K over a temperature range of 100° C. to 200° C. 
     
     
         18 . The sintered powder metal part of  claim 16 , wherein the powder metal part has an ultimate tensile strength of between 100 and 140 MPa and a yield strength of between 90 and 105 MPa.