CN108103368A - The tough as-cast aluminum alloy of novel high-strength and preparation method - Google Patents

Abstract

The invention relates to a novel high-strength and toughness cast aluminum alloy and a preparation method thereof, comprising the following four steps: (1) proportioning and melting of the aluminum alloy; (2) refining of the aluminum alloy; (3) strengthening the aluminum alloy with trace nanoparticles; (4) Aluminum alloy casting molding. The technical solution involved in the present invention is to design, smelt, and refine the aluminum alloy composition, then add a small amount of nano-TiB ₂ , NbB ₂ , TiC particles to strengthen the aluminum alloy, and strictly control the content of Fe, Ti, and Zn impurity elements to prepare a A new type of cast aluminum alloy with high strength and toughness without heat treatment. The cast aluminum alloy prepared by this process exhibits excellent strength and plasticity. This product can be used to prepare large aluminum alloy structural parts without heat treatment, which saves a lot of tooling, man-hours and labor required for correction during heat treatment and after heat treatment, reduces energy consumption, simplifies the production process of aluminum alloy structural parts, and reduces preparation costs. , has important application value.

Description

Novel high strength and toughness cast aluminum alloy and preparation method thereof

technical field

The invention relates to the field of aluminum alloy processing and preparation, in particular to a novel high-strength and tough cast aluminum alloy and a preparation method.

Background technique

At present, with the rapid development of my country's automobile industry, the pursuit of lighter, faster and more environmentally friendly concepts has gradually become the core strategic goal of the automobile industry. Automobile independent innovation urgently needs advanced, lightweight, high-strength and high-strength materials and manufacturing technologies for key automotive parts. At present, in my country's automobile industry, most of the body-in-white is made of steel. Although steel has the characteristics of high strength and good impact resistance, its density is relatively high, making it difficult to reduce the weight of automobiles. As an alloy with low density, high specific strength and good corrosion resistance, aluminum alloy will gradually replace some steel stamping parts and become an important part of lightweight development. Using aluminum alloy instead of steel can reduce the overall body weight by nearly 50%. Therefore, the production and research and development of aluminum alloy structural parts and their materials, especially the research and development of large and complex aluminum alloy structural parts and their materials are very important. important practical significance. Some of the large and complex aluminum alloy structural parts that can be applied to passenger cars in the early stage are mostly die-casting parts. Generally, die-casting parts cannot be heat-treated, so they have low strength and poor plasticity, and cannot meet the plasticity and safety requirements required for body structural parts. Other casting methods such as vacuum die casting, low pressure casting and tilting casting, although these methods can be heat treated, the subsequent heat treatment process is more complicated, and the deformation of the heat treated aluminum alloy at high temperature is serious, and subsequent heat treatment of the aluminum alloy is required. Calibration of alloy structural parts will further increase the requirements for energy consumption, tooling, working hours, and labor, prolong the manufacturing cycle, and increase manufacturing costs. Based on the above reasons, the current automobile manufacturing industry is in urgent need of a new type of cast aluminum alloy with high strength and toughness that does not require subsequent heat treatment. Nano-TiB ₂ , NbB ₂ , TiC ceramic particles have the characteristics of high melting point, high hardness, good corrosion resistance and high electrical conductivity, etc., and are small in size and large in number. The strength, Plasticity has been significantly improved. A good strengthening effect can be obtained with a low content of ceramic particles, which also makes the preparation process simple and the cost easy to control. The as-cast aluminum alloy strengthened by nanoparticles can be directly used in the preparation of structural parts without any subsequent heat treatment process, which greatly simplifies the production process of aluminum alloy. The technical solution involved in the present invention is to prepare a new type of high-strength and tough cast alloy without heat treatment by designing, smelting, and refining the aluminum alloy composition, and then adding nano-ceramic particles to strengthen the aluminum alloy, while strictly controlling the content of Fe, Ti, and Zn impurity elements. state aluminum alloy. The strength and plasticity of the aluminum alloy prepared by the preparation method involved in this patent are greatly improved. This solution can avoid the heat treatment process of large aluminum alloy components, and save a lot of tooling, man-hours and labor required for heat treatment and correction after heat treatment. At the same time Reducing energy consumption has important application value for simplifying alloy production process and reducing cost.

Contents of the invention

The problem to be solved by the present invention is to provide a novel high-strength and toughness cast aluminum alloy and a preparation method thereof.

The purpose of the present invention can be achieved through the following technical solutions:

A novel high-strength and toughness cast aluminum alloy and a preparation method thereof, comprising the following steps:

(1) Step 1, aluminum alloy proportioning and smelting:

Raw materials are prepared with pure aluminum, Al-Si ₁₂ master alloy, pure magnesium and pure copper.

According to the composition of aluminum alloy: Si: 9.30wt.% ~ 10.5wt.%; Mg: 0.39wt.% ~ 2.70wt.%; Cu: 0.00wt.% ~ 1.00wt.%; Zn: ≤0.15wt.% ; Ti: ≤0.10wt.%; Fe: ≤0.10wt.%; the balance is Al, and the aluminum alloy is prepared. Add the raw materials for preparing aluminum alloy into a dry melting furnace, heat to 1003-1023K and smelt for 0.5h-1h to obtain aluminum alloy melt;

(2) Step two, aluminum alloy refining:

The smelted aluminum liquid is transferred to the holding furnace for heat preservation, and then refined in the furnace. At a temperature of 1003-1023K, the rotating air blowing probe is extended into the bottom of the holding furnace, and chlorine and argon are introduced into the aluminum liquid through the rotating air blowing probe. Refining with gas, blowing gas for 5-10 minutes, and using an online hydrogen detector to measure the liquid hydrogen content of the aluminum liquid during refining.

(3) Step 3, micro-nanoparticle-strengthened aluminum alloy:

30wt.% TiB ₂ /Al, 30wt.% NbB 2 /Al _, 30wt.% TiC/Al master alloys containing endogenous nano-ceramic particles were respectively added after the gas purification melt was completed. The actual amount of nano-TiB ₂ , NbB ₂ , and TiC ceramic particles added is 0.02-0.3wt.%, and mechanically stirred for 2-5 minutes; the ultrasonic probe is lowered to 100 mm below the liquid surface and kept warm for 3-8 minutes; then the ultrasonic equipment is turned on, and the mixed The alloy liquid is ultrasonically treated for 3-10 minutes to assist the uniform dispersion of nanoparticles. The alloy liquid after ultrasonic treatment is added with 0.05-0.10wt.% aluminum alloy refining agent for degassing and refining, slag removal, and standing for 5-10 minutes; the aluminum liquid after the final slag removal treatment can be directly cast;

(4) Step 4, aluminum alloy casting molding:

Cast aluminum liquid into a series of metal molds to form a plate-shaped aluminum alloy casting slab, the thickness of the plate-shaped casting slab is 20mm, and the casting control temperature is 973-1003K;

Preferably, the refining agent components in step three are: 35-50wt.% KCl, 30-40wt.% MgCl ₂ , 5-10wt.% AlF ₃ , 10-15wt.% Na ₃ AlF6, 5-10wt.% Mg ₃ N ₂ , 2-5 wt.% Na ₂ CO ₃ , 2-5 wt.% C ₂ Cl ₆ .

Preferably, the material of the metal mold in step 4 is: 45# steel. The size of the metal mold is: 200mm×150mm×20mm.

The beneficial effect of the invention is that: the invention relates to a novel high-strength and toughness cast aluminum alloy and its preparation method, including the following four steps: (1) aluminum alloy proportioning and smelting; (2) aluminum alloy refining; (3) trace nanoparticles Reinforced aluminum alloy; (4) Aluminum alloy casting. The technical solution involved in the present invention is to design, smelt, and refine the aluminum alloy composition, then add a small amount of nano-TiB ₂ , NbB ₂ , TiC particles to strengthen the aluminum alloy, and strictly control the content of Fe, Ti, and Zn impurity elements to prepare a A new type of cast aluminum alloy with high strength and toughness without heat treatment. The cast aluminum alloy prepared by this process exhibits excellent strength and plasticity. This product can be used to prepare large aluminum alloy structural parts without heat treatment, which saves a lot of tooling, man-hours and labor required for correction during heat treatment and after heat treatment, reduces energy consumption, simplifies the production process of aluminum alloy structural parts, and reduces preparation costs. , has important application value.

Detailed ways

In order to make the technical means, innovative features, and goals achieved by the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments.

Example 1:

A kind of novel high-strength and toughness cast aluminum alloy of this example and preparation method, comprise the following steps:

(1) Step 1, proportioning and smelting of aluminum alloy: prepare raw materials with pure aluminum, Al-Si ₁₂ master alloy, pure magnesium and pure copper. According to the composition of aluminum alloy: Si: 9.80wt.%; Mg: 0.39wt.%; Cu: 1.00wt.%; Zn: ≤0.15wt.%; Ti: ≤0.10wt.%; Fe: ≤0.10wt.% %; the balance is Al, the preparation of aluminum alloy. Add the raw materials for preparing aluminum alloy into a dry melting furnace, heat to 1023K and melt for 0.5h to obtain aluminum alloy melt;

(2) Step 2, aluminum alloy refining: transfer the smelted aluminum liquid to the holding furnace for heat preservation, and then carry out refining in the furnace. Feed chlorine and argon into the molten aluminum for refining, blow it for 5 minutes, and use an online hydrogen detector to measure the liquid hydrogen content of the molten aluminum during refining.

(3) Step 3, micro-nanoparticle-strengthened aluminum alloy:

30wt.% TiB ₂ /Al master alloys containing endogenous nano-ceramic particles were respectively added after the gas purification melt was completed. The actual amount of nano _-TiB2 ceramic particles added is 0.3wt.%, and mechanically stirred for 5 minutes; the ultrasonic probe is lowered to 100mm below the liquid surface and kept warm for 5 minutes; then the ultrasonic equipment is turned on, and the mixed alloy liquid is ultrasonically treated for 10 minutes to assist in the dispersion of nanoparticles uniform. The alloy liquid after ultrasonic treatment is added with 0.10wt.% aluminum alloy refining agent for degassing and refining, slag removal, and standing for 10 minutes; the aluminum liquid after the final slag removal treatment can be directly cast;

(4) Step 4, aluminum alloy casting molding:

Cast the molten aluminum into a series of metal molds to form a plate-shaped aluminum alloy casting slab, the thickness of the plate-shaped casting slab is 20mm, and the casting control temperature is 1003K;

Wherein, the refining agent composition in step three is: 35wt.% KCl, 45wt.% MgCl ₂ , 5wt.% AlF ₃ , 5wt.% Na ₃ AlF6, 5wt.% Mg ₃ N ₂ , 3wt.% Na ₂ CO _3. 2 wt.% C ₂ Cl ₆ .

Wherein, the material of the metal mold in step 4 is: 45# steel. The size of the metal mold is: 200mm×150mm×20mm.

In the example 1, the Al-Si ₁₀ -Cu ₁ -Mg _0.39 aluminum alloy strengthened by 0.3wt.% TiB ₂ nanoparticles has excellent mechanical properties in the as-cast state: the yield strength is 135.5 MPa, and the tensile strength is 271.6MPa, elongation 13.0%. As shown in Table 1.

Example 2:

A kind of novel high-strength and toughness cast aluminum alloy of this example and preparation method, comprise the following steps:

(1) Step 1, proportioning and smelting of aluminum alloy: prepare raw materials with pure aluminum, Al-Si ₁₂ master alloy, pure magnesium and pure copper. According to the composition of aluminum alloy: Si: 10.2wt.%; Mg: 0.39wt.%; Cu: 1.00wt.%; Zn: ≤0.15wt.%; Ti: ≤0.10wt.%; Fe: ≤0.10wt.% %; the balance is Al, the preparation of aluminum alloy. Add the raw materials for preparing aluminum alloy into a dry melting furnace, heat to 1003K and melt for 1 hour to obtain aluminum alloy melt;

(2) Step 2, aluminum alloy refining: the smelted aluminum liquid is transferred to the holding furnace for heat preservation, and then refined in the furnace. Chlorine and argon are introduced into the molten aluminum for refining, blown for 8 minutes, and the liquid hydrogen content of the molten aluminum is measured by an online hydrogen detector during refining.

(3) Step 3, micro-nanoparticle-strengthened aluminum alloy:

30wt.% NbB ₂ /Al master alloys containing endogenous nano-ceramic particles were respectively added after the gas purification melt was finished. The actual amount of nano _-NbB2 ceramic particles added is 0.3wt.%, and mechanically stirred for 5 minutes; the ultrasonic probe is lowered to 100 mm below the liquid surface and kept warm for 8 minutes; then the ultrasonic equipment is turned on, and the mixed alloy liquid is ultrasonically treated for 5 minutes to assist in the dispersion of nanoparticles uniform. The alloy liquid after ultrasonic treatment is added with 0.05wt.% aluminum alloy refining agent for degassing and refining, slag removal, and standing for 5 minutes; the aluminum liquid after the final slag removal treatment can be directly cast;

(4) Step 4, aluminum alloy casting molding:

Cast aluminum liquid into a series of metal molds to form a plate-shaped aluminum alloy billet, the thickness of the plate-shaped billet is 20mm, and the casting control temperature is 973K;

Wherein, the refining agent composition in step three is: 45wt.% KCl, 30wt.% MgCl ₂ , 5wt.% AlF ₃ , 11wt.% Na ₃ AlF6, 5wt.% Mg ₃ N ₂ , 2wt.% Na ₂ CO _3. 2 wt.% C ₂ Cl ₆ .

Wherein, the material of the metal mold in step 4 is: 45# steel. The size of the metal mold is: 200mm×150mm×20mm.

In the example 2, the Al-Si ₁₀ -Cu ₁ -Mg _0.39 aluminum alloy strengthened by 0.3wt.% NbB ₂ nanoparticles has excellent mechanical properties in the as-cast state: the yield strength is 141.7MPa, and the tensile strength is 276.8MPa, elongation 12.4%. As shown in Table 1.

Example 3:

A kind of novel high-strength and toughness cast aluminum alloy of this example and preparation method, comprise the following steps:

(1) Step 1, proportioning and smelting of aluminum alloy: prepare raw materials with pure aluminum, Al-Si ₁₂ master alloy and pure magnesium. According to the composition of aluminum alloy: Si: 9.30wt.%; Mg: 2.60wt.%;; Zn: ≤0.15wt.%; Ti: ≤0.10wt.%; Fe: ≤0.10wt.%; , the preparation of aluminum alloy. Add the raw materials for preparing aluminum alloy into a dry melting furnace, heat to 1023K and melt for 0.5h to obtain aluminum alloy melt;

(2) Step two, aluminum alloy refining:

The smelted aluminum liquid is transferred to the holding furnace for heat preservation, and then refined in the furnace. At a temperature of 1023K, the rotating air blowing probe is inserted into the bottom of the holding furnace, and chlorine and argon are introduced into the aluminum liquid through the rotating air blowing probe. Refining, gas blowing treatment for 10 minutes, during refining, use an online hydrogen detector to measure the liquid hydrogen content of the aluminum liquid.

(3) Step 3, micro-nanoparticle-strengthened aluminum alloy:

30wt.% NbB ₂ /Al master alloys containing endogenous nano-ceramic particles were respectively added after the gas purification melt was finished. The actual amount of nano- _NbB2 ceramic particles added is 0.02wt.%, and mechanically stirred for 3 minutes; the ultrasonic probe is lowered to 100mm below the liquid surface and kept warm for 5 minutes; then the ultrasonic equipment is turned on, and the mixed alloy liquid is ultrasonically treated for 5 minutes to assist in the dispersion of nanoparticles uniform. The alloy liquid after ultrasonic treatment is added with 0.05wt.% aluminum alloy refining agent for degassing and refining, slag removal, and standing for 6 minutes; the aluminum liquid after the final slag removal treatment can be directly cast;

(4) Step 4, aluminum alloy casting molding:

Cast the molten aluminum into a series of metal molds to form a plate-shaped aluminum alloy casting slab, the thickness of the plate-shaped casting slab is 20mm, and the casting control temperature is 1003K;

Wherein, the refining agent composition in Step 3 is: 40wt.% KCl, 35wt.% MgCl ₂ , 6wt.% AlF ₃ , 10wt.% Na ₃ AlF6, 5wt.% Mg ₃ N ₂ , 2wt.% Na ₂ CO _3. 2 wt.% C ₂ Cl ₆ .

Wherein, the material of the metal mold in step 4 is: 45# steel. The size of the metal mold is: 200mm×150mm×20mm.

In the example 3, the Al-Si ₁₀ -Mg _2.6 aluminum alloy strengthened by 0.02wt.% NbB ₂ nanoparticles has excellent mechanical properties in the as-cast state: yield strength is 187.9MPa, tensile strength is 269.2MPa, The elongation was 9.8%. As shown in Table 1.

Example 4:

A kind of novel high-strength and toughness cast aluminum alloy of this example and preparation method, comprise the following steps:

(1) Step 1, aluminum alloy proportioning and smelting:

Prepare raw materials with pure aluminum, Al-Si ₁₂ master alloy and pure magnesium.

According to the composition of aluminum alloy: Si: 10.5wt.%; Mg: 2.70wt.%; Zn: ≤0.15wt.%; Ti: ≤0.10wt.%; Fe: ≤0.10wt.%; Formulated aluminum alloy. Add the raw materials for preparing aluminum alloy into a dry melting furnace, heat to 1023K and melt for 0.5h to obtain aluminum alloy melt;

(2) Step two, aluminum alloy refining:

The smelted aluminum liquid is transferred to the holding furnace for heat preservation, and then refined in the furnace. At a temperature of 1023K, the rotating air blowing probe is inserted into the bottom of the holding furnace, and chlorine and argon are introduced into the aluminum liquid through the rotating air blowing probe. Refining, gas blowing treatment for 10 minutes, during refining, use an online hydrogen detector to measure the liquid hydrogen content of the aluminum liquid.

(3) Step 3, micro-nanoparticle-strengthened aluminum alloy:

30wt.% TiC/Al master alloy containing endogenous nano-ceramic particles was added after the gas purification melt was finished. The actual amount of nano-TiC ceramic particles added is 0.02wt.%, mechanically stirred for 2 minutes; the ultrasonic probe is lowered to 100mm below the liquid surface and kept warm for 6 minutes; then the ultrasonic equipment is turned on, and the mixed alloy liquid is ultrasonically treated for 3 minutes to assist the uniform dispersion of nanoparticles . The alloy liquid after ultrasonic treatment is added with 0.10wt.% aluminum alloy refining agent for degassing and refining, slag removal, and standing for 10 minutes; the aluminum liquid after the final slag removal treatment can be directly cast;

(4) Step 4, aluminum alloy casting molding:

Cast the molten aluminum into a series of metal molds to form a plate-shaped aluminum alloy casting slab, the thickness of the plate-shaped casting slab is 20mm, and the casting control temperature is 1003K;

Wherein, Ti/C=1:1 of the TiC nanoparticles in the 30wt.% TiC/Al master alloy mentioned in the third step.

Wherein, the refining agent composition in step three is: 40wt.% KCl, 30wt.% MgCl ₂ , 6wt.% AlF ₃ , 10wt.% Na ₃ AlF6, 6wt.% Mg ₃ N ₂ , 4wt.% Na ₂ CO _3. 4 wt.% C ₂ Cl ₆ .

Wherein, the material of the metal mold in step 4 is: 45# steel. The size of the metal mold is: 200mm×150mm×20mm.

In the example 4, the Al-Si ₁₀ -Mg _2.6 aluminum alloy treated with 0.3wt.% TiC nanoparticles has excellent mechanical properties in the as-cast state: the yield strength is 181.0MPa, the tensile strength is 277.2MPa, and the tensile strength is 277.2MPa. The rate was 9.1%. As shown in Table 1.

Example 5:

A kind of novel high-strength and toughness cast aluminum alloy of this example and preparation method, comprise the following steps:

(1) Step 1, aluminum alloy proportioning and smelting:

Raw materials are prepared with pure aluminum, Al-Si ₁₂ master alloy, pure magnesium and pure copper.

According to the composition of aluminum alloy: Si: 9.5wt.%; Mg: 2.60wt.%; Zn: ≤0.15wt.%; Ti: ≤0.10wt.%; Fe: ≤0.10wt.%; Formulated aluminum alloy. Add the raw materials for preparing aluminum alloy into a dry melting furnace, heat to 1003K and melt for 1 hour to obtain aluminum alloy melt;

(2) Step two, aluminum alloy refining:

The smelted aluminum liquid is transferred to the holding furnace for heat preservation, and then refined in the furnace. At a temperature of 1003K, the rotating air blowing probe is inserted into the bottom of the holding furnace, and chlorine and argon are introduced into the aluminum liquid through the rotating air blowing probe. Refining, gas blowing treatment for 6 minutes, using an online hydrogen detector to measure the liquid hydrogen content of the aluminum liquid during refining.

(3) Step 3, micro-nanoparticle-strengthened aluminum alloy:

30wt.% TiB ₂ /Al master alloys containing endogenous nano-ceramic particles were respectively added after the gas purification melt was finished. The actual amount of nano _-TiB2 ceramic particles added is 0.02wt.%, and mechanically stirred for 5 minutes; the ultrasonic probe is lowered to 100mm below the liquid surface and kept warm for 3 minutes; then the ultrasonic equipment is turned on, and the mixed alloy liquid is ultrasonically treated for 3 minutes to assist in the dispersion of nanoparticles uniform. The alloy liquid after ultrasonic treatment is added with 0.10wt.% aluminum alloy refining agent for degassing and refining, slag removal, and standing for 8 minutes; the aluminum liquid after the final slag removal treatment can be directly cast;

(4) Step 4, aluminum alloy casting molding:

Cast aluminum liquid into a series of metal molds to form a plate-shaped aluminum alloy billet, the thickness of the plate-shaped billet is 20mm, and the casting control temperature is 973K;

Wherein, the refining agent composition in step three is: 40wt.% KCl, 32wt.% MgCl ₂ , 8wt.% AlF ₃ , 6wt.% Na ₃ AlF6, 9wt.% Mg ₃ N ₂ , 2wt.% Na ₂ CO _3. 3 wt.% C ₂ Cl ₆ .

Wherein, the material of the metal mold in step 4 is: 45# steel. The size of the metal mold is: 200mm×150mm×20mm.

In the example 5, the Al-Si _9.5 -Mg _2.6 aluminum alloy strengthened by 0.3wt.% TiB ₂ nanoparticles has excellent mechanical properties in the as-cast state: yield strength is 189.2MPa, tensile strength is 282.7MPa, The elongation was 10.2%. As shown in Table 1.

Table 1 shows the values of yield strength, tensile strength and elongation of aluminum alloys in Examples 1-5 under different alloy compositions, different refining processes, and different treatment processes for strengthening aluminum alloys with micro-nanoparticles.

Table 1

sample Yield strength (MPa) Tensile strength (MPa) Elongation (%) Implementation example 1 135.5 271.6 13.0 Implementation example 2 141.7 276.8 12.4 Implementation example 3 187.9 269.2 9.8 Implementation example 4 181.0 277.2 9.1 Implementation Example 5 189.2 282.7 10.2

The above description is a preferred embodiment of the present invention, and it should be pointed out that for those skilled in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications are also considered Be the protection scope of the present invention.

Claims (3)

1. a kind of tough as-cast aluminum alloy of novel high-strength and preparation method, it is characterised in that：Comprise the following steps：

(1) aluminium alloy matches somebody with somebody when melting：With fine aluminium, Al-Si₁₂Intermediate alloy, pure magnesium, fine copper are material preparation, according to aluminium alloy Ingredient be：Si：9.30wt.%~10.5wt.%；Mg：0.39wt.%~2.70wt.%；Cu：0.00wt.%~ 1.00wt.%；Zn：≤ 0.15wt.%；Ti：≤ 0.10wt.%；Fe：≤ 0.10wt.%；Surplus is Al, prepares aluminium alloy；It will The raw material for preparing aluminium alloy is added to together in dry smelting furnace, is heated to temperature as melting 0.5h under the conditions of 1003-1023K ~1h, obtains molten aluminium alloy；

(2) alloy refining：Smelting molten aluminum goes to holding furnace heat preservation, then carries out furnace refining, is 1003- in temperature Under the conditions of 1023K, will rotation blow probe stretch into heat preservation furnace bottom, from rotation blow probe to molten aluminum be passed through chlorine and argon gas into Row refining, blow processing 5-10min, measures the liquid hydrogen content of molten aluminum during refining using online hydrogen meter；

(3) micro reinforced by nanoparticles aluminium alloy：It is separately added into after gas purification melt containing interior raw nano-ceramic particle 30wt.%TiB₂/ Al, 30wt.%NbB₂/ Al, 30wt.%TiC/Al intermediate alloys；Wherein nanometer TiB₂、NbB₂, TiC pottery The porcelain particle amount of being actually added into is 0.02-0.3wt.%, mechanical agitation 2-5min；Ultrasonic probe is dropped to below liquid level 100mm simultaneously keeps the temperature 3-8min；Later on ultrasonic equipment, to hybrid alloys liquid using supersound process 3-10min, aided nano Particle is uniformly dispersed；Aluminium alloy after supersound process adds in 0.05-0.10wt.% aluminum refining agents and carries out refinery by de-gassing, takes off Slag stands 5-10min；It can directly cast by the molten aluminum for finally removing Slag treatment；

(4) aluminium alloy casting：Molten aluminum is cast in a series of metal type dies into plate aluminium alloy strand, plate strand Thickness for 20mm, cast controlled at 973-1003K.

2. the tough as-cast aluminum alloy of novel high-strength according to claim 1 and preparation method, it is characterised in that：Institute in step 3 Stating refining agent ingredient is：35-50wt.%KCl, 30-40wt.%MgCl₂, 5-10wt.%AlF₃, 10-15wt.%Na₃AlF6、 5-10wt.%Mg₃N₂, 2-5wt.%Na₂CO₃, 2-5wt.%C₂Cl₆。

3. the tough as-cast aluminum alloy of novel high-strength according to claim 1 and preparation method, it is characterised in that：It is golden in step 4 The material of genotype mold is：45# steel；The size of metal type dies is：200mm×150mm×20mm.