Semi-solid die-casting aluminum alloy and method for preparing semi-solid die-casting aluminum alloy casting

Abstract

The present disclosure provides a semi-solid die-casting aluminum alloy and a method for preparing a semi-solid die-casting aluminum alloy casting. The semi-solid die-casting aluminum alloy contains alloying elements, inevitable impurities and the balance of aluminum element. Based on the total weight of the semi-solid die-casting aluminum alloy, the alloying elements include: 7.5 to 9.5 wt % of Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75 wt % of Mn, 0.01 to 0.5 wt % of Ti and 0.01 to 0.35 wt % of rare earth element.

1 . A semi-solid die-casting aluminum alloy, comprising:
 alloying elements, inevitable impurities, and a balance of aluminum element,   wherein based on a total weight of the semi-solid die-casting aluminum alloy, the alloying elements comprise:   7.5 to 9.5 wt % of Si,   3.5 to 4.8 wt % of Cu,   0.5 to 0.75 wt % of Mn,   0.01 to 0.5 wt % of Ti, and   0.01 to 0.35 wt % of rare earth element.   
     
     
         2 . The semi-solid die-casting aluminum alloy according to  claim 1 , wherein based on the total weight of the semi-solid die-casting aluminum alloy, the alloying elements comprise:
 8.0 to 9.0 wt % of Si,   3.5 to 4.5 wt % of Cu,   0.5 to 0.6 wt % of Mn,   0.05 to 0.25 wt % of Ti, and   0.15 to 0.25 wt % of rare earth element.   
     
     
         3 . The semi-solid die-casting aluminum alloy according to  claim 1 , wherein the rare earth element comprises at least one of La, Ce, Pr and Nd. 
     
     
         4 . The semi-solid die-casting aluminum alloy according to  claim 1 , wherein the impurities in the semi-solid die-casting aluminum alloy are not more than 0.8 wt %. 
     
     
         5 . The semi-solid die-casting aluminum alloy according to  claim 1 , wherein the ratio of the weight content of Ti to Cu is 1:(14 to 90). 
     
     
         6 . The semi-solid die-casting aluminum alloy according to  claim 4 , wherein the semi-solid die-casting aluminum alloy comprises 7.5 to 9.5 wt % of Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75 wt % of Mn, 0.01 to 0.5 wt % Ti, 0.01 to 0.35 wt % of rare earth element, no more than 0.8 wt % of impurities and the balance of aluminum. 
     
     
         7 . The semi-solid die-casting aluminum alloy according to  claim 6 , wherein the semi-solid die-casting aluminum alloy comprises 8.0 to 9.0 wt % of Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6 wt % of Mn, 0.05 to 0.25 wt % Ti, 0.15 to 0.25 wt % of rare earth element, no more than 0.7 wt % of impurities and the balance of aluminum. 
     
     
         8 . The semi-solid die-casting aluminum alloy according to  claim 1 , wherein the semi-solid die-casting aluminum alloy has a tensile strength of not less than 370 MPa, a yield strength of not less than 290 MPa, and an elongation of not less than 5.5%. 
     
     
         9 . The semi-solid die-casting aluminum alloy according to  claim 2 , wherein the semi-solid die-casting aluminum alloy has a tensile strength of not less than 380 MPa, a yield strength of not less than 300 MPa, and an elongation of not less than 6%. 
     
     
         10 . A method for preparing a semi-solid die-casting aluminum alloy casting, comprising:
 after performing ratio smelting on aluminum alloy raw materials, performing semi-solid die casting to obtain the semi-solid die-casting aluminum alloy casting,   wherein the aluminum alloy raw materials are such that the obtained semi-solid die-casting aluminum alloy casting comprises:   based on the total weight of the aluminum alloy casting, 7.5 to 9.5 wt % of Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75 wt % of Mn, 0.01 to 0.5 wt % of Ti, 0.01 to 0.35 wt % of rare earth element, and the balance of aluminum and inevitable impurities.   
     
     
         11 . The method according to  claim 10 , wherein the aluminum alloy raw materials are such that the obtained semi-solid die-casting aluminum alloy casting comprises: based on the total weight of the semi-solid die-casting aluminum alloy casting, 8.0 to 9.0 wt % of Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6 wt % of Mn, 0.05 to 0.25 wt % of Ti, 0.15 to 0.25 wt % of rare earth element, and the balance of aluminum and inevitable impurities. 
     
     
         12 . The method according to  claim 10 , wherein the aluminum alloy raw material is elemental metals or metal alloys. 
     
     
         13 . The method according to  claim 12 , wherein the aluminum alloy raw materials are elemental aluminum or an alloy of aluminum, elemental silicon or an alloy of silicon, elemental copper or an alloy of copper, elemental manganese or an alloy of manganese, elemental titanium or an alloy of titanium, and an elemental rare earth element or an alloy containing a rare earth element. 
     
     
         14 . The method according to  claim 12 , wherein the aluminum alloy raw materials are elemental aluminum, an Al—Si alloy, an Al—Ti alloy, an Al—Cu alloy, an Al—Mn alloy and an Al—Re intermediate alloy. 
     
     
         15 . The method according to  claim 12 , wherein the purity of the elemental metal is 99.9 wt % or more, and the total content of the alloying elements in the metal alloy is 99.9 wt % or more.