AlSiMgX MASTER ALLOY AND USE OF THE MASTER ALLOY IN THE PRODUCTION OF AN ALUMINIUM ALLOY

Abstract

The invention relates to an AlSiMgX master alloy, especially suitable for increasing the Magnesium concentration of aluminium foundry alloy melts. The invention also relates to a process for increasing the Mg content of aluminium foundry alloys by use of the AlSiMgX master alloy in preparing a target aluminium alloy. The AlSiMgX master alloy comprises: Mg 1.3-6.5 wt %, Si 6.5-11.5 wt %, Cu 0-1 wt %, Mn 0-1.0 wt %, Fe≤0.40 wt %, Ti≤0.18 wt %, Sr≤0.10 wt %, balance Al and incidental impurities.

1 . An AlSiMgX master alloy for increasing the content of Mg in an aluminium base alloy in the preparation of a target aluminium alloy, the AlSiMgX master alloy comprises:
 Mg 1.3-6.5 wt %;   Si 6.5-11.5 wt %;   Cu 0-1.0 wt %;   Mn 0-1.0 wt %;   Fe≤0.40 wt %;   Ti≤0.18 wt %;   Sr≤0.10 wt %; and   balance Al and incidental impurities.   
     
     
         2 . The AlSiMgX master alloy according to  claim 1 , wherein the content of Si is 6.5-7.5 wt %, or 9.0-11.5 wt %. 
     
     
         3 . The AlSiMgX master alloy according to  claim 1 , wherein the content of Si is 6.5-11.5 wt % and the content of Mn is 0.4-0.8 wt %. 
     
     
         4 . The AlSiMgX master alloy according to  claim 3 , wherein the content of Si is 6.5-8.5 wt %, or 9.0-11.5, and the content of Mn is 0.4-0.8 wt %. 
     
     
         5 . The AlSiMgX master alloy according to  claim 1 , wherein the content of Si is 6.5-7.5 wt % and the content of Cu is 0.2-0.7 wt %. 
     
     
         6 . The AlSiMgX master alloy according to  claim 1 , wherein the content of Sr is 0.02-0.04 wt %. 
     
     
         7 . The AlSiMgX master alloy according to  claim 1 , wherein the content of Fe is ≤0.15 wt %. 
     
     
         8 . The AlSiMgX master alloy according to  claim 1 , wherein the content of Ti is 0.05-0.15 wt %. 
     
     
         9 . The AlSiMgX master alloy according to  claim 1 , wherein the Mg content is 1.3-5.5 wt %; 1.3-2.5 wt %; 1.5-2.5 wt %; 1.5-2.0 wt %; 2.0-3.0 wt %; 2.5-3.5 wt %; 3.4-4.0 wt %; 4.0-5.5 wt %; 4.5-5.5 wt %, or 4.0-4.6 wt %. 
     
     
         10 . The AlSiMgX master alloy according to  claim 1 , wherein the master alloy is based on 3xx alloy (according to the Aluminium Association designation system), EN AC-42xxx, EN AC-43500 (AlSi10MnMg) or EN AC-45500 (AlSi7Cu0.5 Mg) alloy (according to European Standard EN1706 and/or EN 1676), having an increased Mg concentration compared to the said standard alloys. 
     
     
         11 . The AlSiMgX master alloy according to  claim 1 , where the AlSiMgX master alloy is in the form of an ingot, rod, wire, pellet, or briquet, foil, waffle, button, rod, powder or splatter. 
     
     
         12 . (canceled) 
     
     
         13 . A method for increasing the content of Mg in an aluminium base alloy in the preparation of a target aluminium alloy, the method comprises
 providing an AlSiMgX master alloy according to  claim 1 ;   providing an aluminium base alloy having essentially the same composition as the AlSiMgX master alloy except the Mg concentration being lower compared to the Mg concentration of the AlSiMgX master alloy;   adding a predetermined amount of the AlSiMgX master alloy to the aluminium base alloy, thereby increasing the Mg content of the aluminium base alloy while keeping the concentration of any other alloying elements essentially unchanged.   
     
     
         14 . The method according to  claim 13 , comprising adding the AlSiMgX master alloy to a melting furnace, prior to, during, or after melting the aluminium base alloy. 
     
     
         15 . The method according to  claim 13 , comprising adding the AlSiMgX master alloy to a transport crucible, prior to, during, or after being filled with molten aluminium base alloy. 
     
     
         16 . The method according to  claim 13 , comprising adding the AlSiMgX master alloy to a holding or casting furnace, prior to, during, or after the aluminium base alloy is being poured in. 
     
     
         17 . The method according to  claim 13 , comprising adding the AlSiMgX master alloy to a continuously melting furnace, wherein the AlSiMgX master alloy is periodically fed to the furnace to compensate Mg-loss. 
     
     
         18 . The method according to  claim 13 , wherein the AlSiMgX master alloy is added in the form of an ingot, rod, wire, pellet, or briquet, foil, waffle, button, rod, powder or splatter. 
     
     
         19 . A method for preparing an AlSiMgX master alloy according to  claim 1 , the method comprises the steps:
 providing an aluminium base alloy in solid or molten state;   optionally, determining the concentration, in weight percent, of each alloying element in the aluminium base alloy;   adding an appropriate amount of Mg into the aluminium base alloy to obtain a desired concentration of Mg in the AlSiMgX master alloy,   optionally, adjusting the amount of any other alloying elements selected from the group consisting of Si, Cu, Fe, Mn, Ti and Sr by adding an appropriate amount of the alloying element(s) to the aluminium base alloy to obtain the desired composition of the AlSiMgX master alloy,   if necessary, adjusting temperature to provide fluidity for casting, and   casting the AlSiMgX master alloy into an ingot, rod, wire, pellet, or briquet.   
     
     
         20 . The method according to  claim 19 , where the aluminium base alloy is chosen from a 3xx series alloy (according to the nomenclature of the Aluminium Association designation system); EN AC-42xxx alloy; EN AC-43500 alloy (AlSi10MnMg) or EN AC-45500 alloy (AlSi7Cu0.5 Mg) (according to European Standard EN1706 and/or EN 1676). 
     
     
         21 - 22 . (canceled) 
     
     
         23 . Use of an AlSiMgX master alloy according to  claim 1 , wherein a predetermined amount of the AlSiMgX master alloy is added to an aluminium base alloy to increase the content of Mg, while the concentration of any other alloying elements in the aluminium base alloy are essentially unchanged.