Aluminum alloy and preparation method thereof

Abstract

An aluminum alloy and a preparation method thereof are provided. In percentage by mass, the aluminum alloy includes: 8-11% of Si, 2-3% of Cu, 0.7-1.1% of Mg, 0.7-1.5% of Mn, 0.01-0.015% of Sr, 0.01-0.015% of Cr, 0-0.4% of Fe, 0.02-0.1% of Ti, 0.01-0.02% of Ga, 0.004-0.02% of B, 0-2% of Zn, and the balance of Al and less than 0.1% of other elements.

What is claimed is: 
     
         1 . An aluminum alloy, in percentage by mass, the aluminum alloy comprising:
 8-11% of Si, 2-3% of Cu, 0.7-1.1% of Mg, 0.7-1.5% of Mn, 0.01-0.015% of Sr, 0.01-0.015% of Cr, 0-0.4% of Fe, 0.02-0.1% of Ti, 0.01-0.02% of Ga, 0.004-0.02% of B, 0-2% of Zn, and the balance of Al and less than 0.1% of other elements.   
     
     
         2 . The aluminum alloy according to  claim 1 , in percentage by mass, the aluminum alloy comprising:
 9-10.8% of Si, 2.5-2.8% of Cu, 0.7-1.1% of Mg, 0.9-1.3% of Mn, 0.01-0.015% of Sr, 0.01-0.015% of Cr, 0-0.4% of Fe, 0.03-0.1% of Ti, 0.01-0.015% of Ga, 0.004-0.01% of B, 0-2% of Zn, and the balance of Al and less than 0.1% of other elements.   
     
     
         3 . The aluminum alloy according to  claim 1 , wherein a mass ratio of Ti to B is (5-10):1. 
     
     
         4 . The aluminum alloy according to  claim 1 , wherein a content of Ga in percentage by mass is greater than a content of Sr in percentage by mass. 
     
     
         5 . The aluminum alloy according to  claim 1 , wherein a content of Si and a content of Cu satisfy the following condition:
   Wt(Si)=(Wt(Cu)−0.2)×(3−5).
   
     
     
         6 . The aluminum alloy according to  claim 1 , wherein a content of Mn and a content of Cu satisfy the following condition:
   Wt(Cu)=(Wt(Mn)−0.3)×(2.5−4).
   
     
     
         7 . The aluminum alloy according to  claim 1 , wherein the other elements comprise one or more of Zr, Ni, Ce, Sc, and Er. 
     
     
         8 . A method for preparing the aluminum alloy according to  claim 1 , comprising the following steps:
 weighing out various raw materials in required proportions based on proportions of all elements in the aluminum alloy, melting the raw materials in a melting furnace to obtain a molten metal, and subjecting the molten metal to slag removal and refining and degassing, and then casting, to obtain an aluminum alloy ingot.   
     
     
         9 . The method according to  claim 8 , wherein the slag removal comprises adding a slag remover into the molten metal, the slag remover comprising one or more of an aluminum alloy slag remover agent NF-1 and an aluminum alloy slag-removal agent DSG. 
     
     
         10 . The method according to  claim 8 , wherein the refining is carried out at 700-710° C., and the refining comprises adding a refining agent into the molten metal, the refining agent comprising one or more of hexafluoroethane and an aluminum refining agent ZS-AJ01C. 
     
     
         11 . The method according to  claim 8 , further comprising:
 die casting the aluminum alloy ingot for formation.   
     
     
         12 . The method according to  claim 11 , comprising carrying out artificial aging on the die-cast aluminum alloy. 
     
     
         13 . The method according to  claim 12 , wherein the artificial aging is carried out at 100-200° C. for 1.5-3 h.