Al-mg-si alloy with scandium for the integral construction of alm structures

Abstract

This relates to an aluminium alloy, a method for producing a lightweight metal workpiece, a lightweight metal workpiece comprising the aluminium alloy, and also the use of the aluminium alloy for producing heat-resistant lightweight metal workpieces by means of additive layer manufacturing (ALM) and/or spraying methods or for engine components, cylinder heads, crank housings, heat-resistant safety component parts, air-conditioning system components, structural aircraft component parts, in particular in the case of supersonic aircraft, power unit segments, pylons, or as coating material for component parts.

1 . An aluminium alloy consisting of:
 3.0 to 6.0% by weight, in relation to the total weight of the alloy, of magnesium (Mg),   >1.0 to 4.0% by weight, in relation to the total weight of the alloy, of silicon (Si),   0.005 to 0.2% by weight, in relation to the total weight of the alloy, of titanium (Ti),   0.1 to 0.75% by weight, in relation to the total weight of the alloy, of scandium (Sc),   0.01 to 0.375% by weight, in relation to the total weight of the alloy, of zirconium (Zr),   0 to 0.5% by weight, in relation to the total weight of the alloy, of at least one element selected from the group consisting of hafnium (Hf), molybdenum (Mo), terbium (Tb), niobium (Nb), gadolinium (Gd), erbium (Er), and vanadium (V),   0 to 0.8% by weight, in relation to the total weight of the alloy, of manganese (Mn),   0 to 0.3% by weight, in relation to the total weight of the alloy, of chromium (Cr),   0 to 1.0% by weight, in relation to the total weight of the alloy, of copper (Cu),   0 to 0.05% by weight, in relation to the total weight of the alloy, of zinc (Zn),   0 to 0.6% by weight, in relation to the total weight of the alloy, of iron (Fe),   0 to 0.004% by weight, in relation to the total weight of the alloy, of beryllium (Be), and   the rest being aluminium with further impurities individually of at most 0.1% by weight in relation to the total weight of the alloy, and on the whole at most 0.5% by weight, in relation to the total weight of the alloy, wherein the amount of zirconium (Zr) and of titanium (Ti) in total corresponds at most to half the amount of scandium (Sc).   
     
     
         2 . The aluminium alloy according to  claim 1 , wherein the alloy contains 3.5 to 5.5% by weight, in relation to the total weight of the alloy, of magnesium (Mg) and/or 1.1 to 4.0% by weight, in relation to the total weight of the alloy, of silicon (Si). 
     
     
         3 . The aluminium alloy according to  claim 1 , wherein the alloy contains 0.01 to 0.2% by weight, in relation to the total weight of the alloy, of titanium (Ti) and/or 0.2 to 0.75% by weight, in relation to the total weight of the alloy, of scandium (Sc). 
     
     
         4 . The aluminium alloy according to  claim 1 , wherein the amount of zirconium (Zr) is <50% of the amount of scandium (Sc). 
     
     
         5 . The aluminium alloy according to  claim 1 , wherein the alloy contains zirconium (Zr) in an amount such that the ratio by weight of scandium (Sc) to zirconium (Zr) is from 2:0.9 to 10:1. 
     
     
         6 . The aluminium alloy according to  claim 1 , wherein the alloy contains zirconium (Zr) and titanium (Ti) in a total amount such that the ratio by weight of scandium (Sc) to zirconium (Zr) and titanium (Ti) is from 2:1 to 10:1. 
     
     
         7 . The aluminium alloy according to  claim 1 , wherein the alloy contains ≧0.001% by weight, in relation to the total weight of the alloy, of at least one element selected from the group consisting of vanadium (V), gadolinium (Gd), chromium (Cr), copper (Cu), and zinc (Zn). 
     
     
         8 . The aluminium alloy according to  claim 1 , wherein the amount of hafnium (Hf) and/or terbium (Tb) corresponds individually to at most ¼ of the amount of scandium (Sc). 
     
     
         9 . The aluminium alloy according to  claim 1 , wherein the alloy contains 0.05 to 0.6% by weight, in relation to the total weight of the alloy, of iron (Fe). 
     
     
         10 . The aluminium alloy according to  claim 1 , wherein the alloy contains ≦0.15% by weight or 0.4 to 0.8% by weight, in relation to the total weight of the alloy, of manganese (Mn). 
     
     
         11 . The aluminium alloy according to  claim 1 , wherein the alloy is provided in the form of a powder comprising particles having an average particle size d 50  of ≦100 μm. 
     
     
         12 . A method for producing a lightweight metal workpiece, said method comprising the following steps:
 providing an aluminium alloy according to  claim 1 ,   producing a lightweight metal workpiece comprising the aluminium alloy by means of additive layer manufacturing (ALM) and/or spraying methods,   cooling the produced lightweight metal workpiece to ≦200° C. with a solidification rate that is ≦10,000,000 K/sec, and   subjecting the cooled lightweight metal workpiece to a heat treatment in a temperature range of from 100 to 400° C.   
     
     
         13 . A lightweight metal workpiece comprising the aluminium alloy according to  claim 1 . 
     
     
         14 . (canceled) 
     
     
         15 . (canceled)