Cast aluminum rare earth high-entropy alloy and preparation method and application thereof

Abstract

The invention belongs to the technical field of cast aluminum alloys, and particularly relates to a cast aluminum rare earth high-entropy alloy and a preparation method and application thereof. The cast aluminum rare earth high-entropy alloy is prepared from the following raw material components in percentage by weight: 0.10 to 0.25 percent of Sc, 0.10 to 0.25 percent of La, 0.10 to 0.25 percent of Ce, 0.10 to 0.25 percent of Pr, 0.10 to 0.25 percent of Nd and the balance of aluminum. In the aluminum rare earth high-entropy alloy, the five rare earth elements including Sc, La, Ce, Pr and Nd exist according to the equal weight ratio or equal molar weight ratio and have the synergistic effect, the defect of combination of one or two elements is overcome, the strengthening effect of each rare earth element is improved, the cocktail effect is achieved, and the casting performance and mechanical performance of the aluminum alloy are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of cast aluminum alloys, and in particular relates to a cast aluminum rare earth high entropy alloy and a preparation method and application thereof. Background Art

[0002] Aluminum alloys are widely used in aerospace, automobiles, ships, construction and building materials due to their low density, high strength, good corrosion resistance and welding performance. Especially under the general trend of energy conservation and consumption reduction, the use of aluminum alloys instead of steel in automobile production will greatly reduce the overall weight of the car. Therefore, the demand for automotive aluminum alloys has increased sharply, and the requirements for automotive aluminum alloys have also been further improved. At present, high-strength, high-ductility, corrosion-resistant and high-performance aluminum alloys have become the focus of research, development and application. There are four major series of cast aluminum alloy systems: Al-Si series, Al-Cu series, Al-Mg series, and Al-Zn series.

[0003] Aluminum-silicon cast aluminum alloy: It has excellent properties such as tensile resistance, fatigue resistance, corrosion resistance, and high specific strength and toughness. In addition to all the properties of cast aluminum alloy, it has higher strength and hardness due to the strengthening effect of silicon particles. It is the most widely used type of cast aluminum alloy. The main alloy grades are ZL101-ZL111.

[0004] Aluminum-copper cast aluminum alloy: ZL201 has good room temperature and high temperature mechanical properties, general plasticity, general welding and cutting performance, but poor fluidity, thermal cracking tendency, poor corrosion resistance, suitable for casting structural parts working at higher temperatures (200-300℃) or parts bearing large dynamic or static loads at room temperature, as well as parts working at low temperatures (-70℃). Sand casting is often used.

[0005] Aluminum-magnesium cast aluminum alloy: ZL301 is the most corrosion-resistant variety among the existing aluminum alloys. It has good cutting and welding performance, high strength, and good anodizing performance. However, the casting process is complicated, the operation is troublesome, and the castings are prone to defects such as looseness and thermal cracking. It is suitable for casting various parts with large loads in corrosive media such as seawater at a working temperature of 150°C, such as various components in marine ship turbines, pump housings, impellers, frames and other parts in the oil industry. Sand casting is mostly used.

[0006] Aluminum-zinc cast aluminum alloy: ZL401 has excellent casting performance, small shrinkage and thermal cracking tendency, high mechanical properties, good welding and cutting performance, but high specific gravity, low plasticity, poor corrosion resistance. It is mostly used for die casting and molds, templates, and structural parts for aircraft, internal combustion engines, vehicles and other products with working temperatures not exceeding 200°C and medium loads. It is mainly used for pressure casting, but also for sand and metal casting.

[0007] Although the above-mentioned aluminum alloy materials can be used in the manufacture of wheel hubs, they generally have problems with insufficient casting performance and mechanical properties.

[0008] Rare earth high entropy alloy is the most effective alloying material discovered so far, and its effect on improving the performance of aluminum alloy is the most prominent. Rare earth high entropy alloy is mainly used as a modifier. Adding rare earth high entropy alloy to Al plays a role in refining the structure. This material has an L12 structure, which is the same as the structure of α-Al, and the mismatch with α-Al is only 0.9%. It can be used as a good heterogeneous nucleation site and a stable modifier. Thereby increasing the number of aluminum alloy grains and refining the grain size. Only a few thousandths of rare earth high entropy elements are added to aluminum alloy, and the strength of aluminum alloy is increased by 1-2 times, the elongation is increased by 4-5 times, and the welding performance can also be significantly improved. Aluminum rare earth high entropy alloy alloyed with cast aluminum alloy has high strength, good toughness, excellent weldability and corrosion resistance, and is a new high-performance structural material.

[0009] Therefore, if a cast aluminum rare earth high entropy alloy that can be used in wheel hubs can be developed, it will have broad market prospects. Summary of the invention

[0010] The present invention aims to solve the above technical problems and provide a cast aluminum rare earth high entropy alloy with excellent casting performance and mechanical properties and a preparation method thereof.

[0011] The technical solution of the present invention is:

[0012] A cast aluminum rare earth high entropy alloy, the raw material components of the cast aluminum rare earth high entropy alloy include:

[0013] Sc 0.10-0.25%, La 0.10-0.25%, Ce 0.10-0.25%, Pr 0.10-0.25%, Nd 0.10-0.25%, and the balance is aluminum.

[0014] Furthermore, the cast aluminum rare earth high entropy alloy includes: Mg 0.30-0.45%, Si 6.50-7.50%, Fe≤0.12%, Cu≤0.10%, Mn≤0.10%, Zn≤0.10%, Ti 0.08-0.20%, Sr 0.01-0.04%, Sc0.10-0.25%, La0.10-0.25%, Ce 0.10-0.25%, Pr 0.10-0.25%, Nd 0.10-0.25%, and the balance is aluminum.

[0015] Furthermore, the cast aluminum rare earth high entropy alloy includes: Fe≤0.12%, Cu4.5-5.3%, Mn0.6-1.0%, Ti0.15-0.37%, Sc 0.10-0.25%, La 0.10-0.25%, Ce 0.10-0.25%, Pr 0.10-0.25%, Nd 0.10-0.25%, and the balance is aluminum.

[0016] Furthermore, the cast aluminum rare earth high entropy alloy comprises: Fe≤0.12%, Mg 9.5-11.5%, Sc 0.10-0.25%, La 0.10-0.25%, Ce 0.10-0.25%, Pr 0.10-0.25%, Nd 0.10-0.25%, and the balance is aluminum.

[0017] Furthermore, the cast aluminum rare earth high entropy alloy comprises: Fe≤0.12%, Si 6-8%, Mg 0.1-0.3%, Zn 9.0-13%, Sc 0.10-0.25%, La 0.10-0.25%, Ce 0.10-0.25%, Pr 0.10-0.25%, Nd0.10-0.25%, and the balance is aluminum.

[0018] The method for preparing the cast aluminum rare earth high entropy alloy of the present invention comprises the following steps:

[0019] (1) reacting a rare earth compound containing Sc, La, Ce, Pr and Nd with an aluminum-containing raw material to obtain an aluminum-rare earth high-entropy master alloy;

[0020] (2) The cast aluminum alloy material is melted, and the aluminum rare earth high entropy intermediate alloy is added thereto for reaction to obtain the cast aluminum rare earth high entropy alloy.

[0021] Furthermore, in step (1), the weight percentage of rare earth elements in the aluminum rare earth high entropy master alloy is 2-10%.

[0022] Furthermore, in step (1), the aluminum-containing raw material is aluminum and / or aluminum alloy.

[0023] Furthermore, in step (2), the cast aluminum alloy material is ZL101 aluminum alloy, ZL201 aluminum-copper alloy, ZL301 aluminum-magnesium alloy or ZL401 aluminum-zinc alloy.

[0024] The present invention also provides an application of a cast aluminum rare earth high entropy alloy in the preparation of a wheel hub product, comprising the following steps: transferring the cast aluminum rare earth high entropy alloy liquid to an electrically heated insulation furnace of a casting machine to cast it into a wheel hub.

[0025] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0026] The present invention adds a rare earth high entropy alloy to the cast aluminum alloy. The main functions of the rare earth high entropy alloy in the aluminum alloy are: improving casting performance, mechanical properties (strength, elongation, welding performance, etc.), corrosion resistance, wear resistance, and high temperature resistance. In the aluminum rare earth high entropy alloy of the present invention, five rare earth elements Sc, La, Ce, Pr, and Nd exist in an equal weight ratio or an equal molar ratio. The synergistic effect overcomes the shortcomings of the combination of one or two elements, improves the strengthening effect of each rare earth element, plays a cocktail effect, and improves the casting performance and mechanical properties of the aluminum alloy.

[0027] The cast aluminum rare earth high entropy alloy wheel hub produced by the present invention has a temperature resistance capability improved by more than 50%, a wear resistance improved by more than 50%, a tensile strength improved by more than 50%, an elongation improved by more than 100%, and a yield rate improved by more than 5%. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Example 1

[0030] (1) reacting a rare earth compound containing Sc, La, Ce, Pr and Nd with aluminum to obtain an aluminum rare earth high entropy master alloy; the weight percentage of the rare earth element in the aluminum rare earth high entropy master alloy is 2%;

[0031] (2) The ZL101 aluminum alloy is smelted at a furnace temperature of 775° C., and then transferred to a refining and heat-insulating gas furnace for refining, and the aluminum rare earth high entropy master alloy is added for reaction to obtain a liquid cast aluminum rare earth high entropy alloy, whose composition is 0.38% Mg, 7.00% Si, 0.12% Fe, 0.10% Cu, 0.10% Mn, 0.10% Zn, 0.14% Ti, 0.03% Sr, 0.10% Sc, 0.10% La, 0.10% Ce, 0.10% Pr, 0.10% Nd 0.10%, the balance is aluminum, the cast aluminum rare earth high entropy alloy liquid is transferred to the electric heating insulation furnace of the casting machine, and the insulation furnace is maintained at a temperature of 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is performed, and the casting pressure is 0.5 atmospheres. Qualified aluminum rare earth high entropy alloy wheel hub castings are cast, and after heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum rare earth high entropy alloy wheel hub finished product is obtained. The casting flash and mechanical turning generated in the casting process can be returned to the smelting process.

[0032] Compared with the wheel hub made of ZL101 aluminum alloy alone, the wheel hub product obtained in this embodiment has a 51% higher heat resistance, a 52% higher wear resistance, a 53% higher tensile strength, a 101% higher elongation, and a 6% higher yield rate.

[0033] Example 2

[0034] (1) reacting a rare earth compound containing Sc, La, Ce, Pr and Nd with aluminum to obtain an aluminum rare earth high entropy master alloy; the weight percentage of the rare earth element in the aluminum rare earth high entropy master alloy is 10%;

[0035] (2) The ZL101 aluminum alloy is smelted at a furnace temperature of 775° C., and then transferred to a refining and heat-insulating gas furnace for refining, and the aluminum rare earth high entropy master alloy is added for reaction to obtain a liquid cast aluminum rare earth high entropy alloy, whose composition is 0.30% Mg, 6.50% Si, 0.12% Fe, 0.10% Cu, 0.10% Mn, 0.10% Zn, 0.08% Ti, 0.01% Sr, 0.25% Sc, 0.25% La, 0.25% Ce, 0.25% Pr, 0.25% Nd 0.25%, the balance is aluminum, the cast aluminum rare earth high entropy alloy liquid is transferred to the electric heating insulation furnace of the casting machine, and the insulation furnace is maintained at a temperature of 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is performed, and the casting pressure is 0.5 atmospheres. Qualified aluminum rare earth high entropy alloy wheel hub castings are cast, and after heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum rare earth high entropy alloy wheel hub finished product is obtained. The casting flash and mechanical turning generated in the casting process can be returned to the smelting process.

[0036] Compared with the wheel hub made of ZL101 aluminum alloy alone, the wheel hub product obtained in this embodiment has a 63% higher heat resistance, a 61% higher wear resistance, a 62% higher tensile strength, a 122% higher elongation, and a 10% higher yield rate.

[0037] Example 3

[0038] (1) reacting a rare earth compound containing Sc, La, Ce, Pr and Nd with aluminum to obtain an aluminum rare earth high entropy master alloy; the weight percentage of the rare earth element in the aluminum rare earth high entropy master alloy is 5%;

[0039] (2) The Zl101 aluminum alloy is smelted at a furnace temperature of 775°C, and then transferred to a refining and heat-insulating gas furnace for refining, and the aluminum rare earth high entropy master alloy is added for reaction to obtain a liquid cast aluminum rare earth high entropy alloy, whose composition is 0.45% Mg, 7.50% Si, 0.12% Fe, 0.10% Cu, 0.10% Mn, 0.10% Zn, 0.20% Ti, 0.04% Sr, 0.18% Sc, 0.18% La, 0.18% Ce, 0.18% Pr, 0.18% Nd 0.18%, the balance is aluminum, the cast aluminum rare earth high entropy alloy liquid is transferred to the electric heating insulation furnace of the casting machine, and the insulation furnace is maintained at a temperature of 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is performed, and the casting pressure is 0.5 atmospheres. Qualified aluminum rare earth high entropy alloy wheel hub castings are cast, and after heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum rare earth high entropy alloy wheel hub finished product is obtained. The casting flash and mechanical turning generated in the casting process can be returned to the smelting process.

[0040] Compared with the wheel hub made of ZL101 aluminum alloy alone, the wheel hub product obtained in this embodiment has a 55% higher heat resistance, a 54% higher wear resistance, a 56% higher tensile strength, a 115% higher elongation, and an 8% higher yield rate.

[0041] Example 4

[0042] (1) reacting a rare earth compound containing Sc, La, Ce, Pr and Nd with aluminum to obtain an aluminum rare earth high entropy master alloy; the weight percentage of the rare earth element in the aluminum rare earth high entropy master alloy is 2%;

[0043] (2) Smelting the ZL201 aluminum-copper alloy at a furnace temperature of 775° C., then transferring it to a refining and heat-insulating gas furnace for refining, adding the aluminum rare earth high entropy master alloy to react, and obtaining a liquid cast aluminum rare earth high entropy alloy having a composition of Fe0.12%, Cu4.9%, Mn0.8%, Ti0.26%, Sc0.10%, La0.10%, Ce0.10%, Pr 0.10%, Nd0.10%, and the balance is aluminum. The cast aluminum rare earth high entropy alloy liquid is transferred to the electric heating insulation furnace of the casting machine, and the insulation furnace is maintained at a temperature of 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is performed, and the casting pressure is 0.5 atmospheres. Qualified aluminum rare earth high entropy alloy wheel hub castings are cast, and after heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum rare earth high entropy alloy wheel hub finished product is obtained. The casting flash and mechanical turning produced in the casting process can be returned to the smelting process.

[0044] Compared with the wheel hub made of ZL201 aluminum-copper alloy alone, the wheel hub product obtained in this embodiment has a 54% higher temperature resistance, a 51% higher wear resistance, a 52% higher tensile strength, a 105% higher elongation, and a 5.5% higher yield rate.

[0045] Example 5

[0046] (1) reacting a rare earth compound containing Sc, La, Ce, Pr and Nd with aluminum to obtain an aluminum rare earth high entropy master alloy; the weight percentage of the rare earth element in the aluminum rare earth high entropy master alloy is 10%;

[0047] (2) The ZL301 aluminum-magnesium alloy is melted at a furnace temperature of 775° C., and then transferred to a refining and heat-insulating gas furnace for refining, and the aluminum rare earth high entropy master alloy is added to react to obtain a liquid cast aluminum rare earth high entropy alloy having a composition of Fe0.12%, Mg10.5%, Sc0.25%, La0.25%, Ce0.25%, Pr0.25%, Nd 0.25%, the balance is aluminum, the cast aluminum rare earth high entropy alloy liquid is transferred to the electric heating insulation furnace of the casting machine, and the insulation furnace is maintained at a temperature of 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is performed, and the casting pressure is 0.5 atmospheres. Qualified aluminum rare earth high entropy alloy wheel hub castings are cast, and after heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum rare earth high entropy alloy wheel hub finished product is obtained. The casting flash and mechanical turning generated in the casting process can be returned to the smelting process.

[0048] Compared with the wheel hub made of ZL301 aluminum-magnesium alloy alone, the wheel hub product obtained in this embodiment has a 66% higher temperature resistance, a 65% higher wear resistance, a 67% higher tensile strength, a 125% higher elongation, and a 7.5% higher yield rate.

[0049] Example 6

[0050] (1) reacting a rare earth compound containing Sc, La, Ce, Pr and Nd with aluminum to obtain an aluminum rare earth high entropy master alloy; the weight percentage of the rare earth element in the aluminum rare earth high entropy master alloy is 5%;

[0051] (2) The ZL401 aluminum-zinc alloy is smelted at a furnace temperature of 775° C., and then transferred to a refining and heat-insulating gas furnace for refining, and the aluminum rare earth high entropy master alloy is added for reaction to obtain a liquid cast aluminum rare earth high entropy alloy having a composition of Fe0.12%, Si7%, Mg0.2%, Zn11%, Sc0.18%, La0.18%, Ce0.18%, Pr 0.18%, Nd0.18%, and the balance is aluminum. The cast aluminum rare earth high entropy alloy liquid is transferred to the electric heating insulation furnace of the casting machine, and the insulation furnace is maintained at 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is carried out, and the casting pressure is 0.5 atmospheres. Qualified aluminum rare earth high entropy alloy wheel hub castings are cast, and after heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum rare earth high entropy alloy wheel hub finished product is obtained. The casting flash and mechanical turning produced in the casting process can be returned to the smelting process.

[0052] Compared with the wheel hub made of ZL401 aluminum-zinc alloy alone, the wheel hub product obtained in this embodiment has 59% higher heat resistance, 58% higher wear resistance, 60% higher tensile strength, 115% higher elongation and 6.5% higher yield.

[0053] In order to further illustrate the technical effects of the present invention, the inventors added the following comparative examples.

[0054] Comparative Example 1

[0055] The difference from Example 1 is that only one rare earth element Sc is added during the preparation process, specifically as follows:

[0056] (1) reacting a rare earth compound containing Sc with aluminum to obtain an aluminum-scandium master alloy; the weight percentage of the scandium element in the aluminum-scandium master alloy is 2%;

[0057] (2) The ZL101 aluminum alloy is melted at a furnace temperature of 775° C., and then transferred to a refining and heat-insulating gas furnace for refining, and the aluminum-scandium master alloy is added for reaction to obtain a liquid casting aluminum-scandium alloy, the composition of which is 0.38% Mg, 7.00% Si, 0.12% Fe, 0.10% Cu, 0.10% Mn, 0.10% Zn, 0.14% Ti, 0.03% Sr, and 0.1% Sc. 0.50%, the balance is aluminum, the casting aluminum-scandium alloy liquid is transferred to the electric heating insulation furnace of the casting machine, and the insulation furnace is maintained at a temperature of 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is performed, and the casting pressure is 0.5 atmospheres. Qualified aluminum-scandium alloy wheel hub castings are cast, and after heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum-scandium alloy wheel hub finished product is obtained. The casting flash and mechanical turning produced in the casting process can be returned to the smelting process.

[0058] Compared with the wheel hub obtained in Example 1, the wheel hub product obtained in this comparative example has a temperature resistance lowered by 8.4%, a wear resistance lowered by 21.3%, a tensile strength lowered by 12.3%, and an elongation lowered by 32.4%.

[0059] Comparative Example 2

[0060] The difference from Example 1 is that only one rare earth element La is added during the preparation process, specifically as follows:

[0061] (1) reacting a rare earth compound containing La with aluminum to obtain an aluminum-lanthanum master alloy; in the aluminum-lanthanum master alloy, the weight percentage of the rare earth element lanthanum is 2%;

[0062] (2) The ZL101 aluminum alloy is melted at a furnace temperature of 775° C., and then transferred to a refining and heat-insulating gas furnace for refining, and the aluminum-lanthanum master alloy is added for reaction to obtain a liquid casting aluminum-lanthanum alloy, the composition of which is 0.38% Mg, 7.00% Si, 0.12% Fe, 0.10% Cu, 0.10% Mn, 0.10% Zn, 0.14% Ti, 0.03% Sr, and 0.12% La. 0.50%, the balance is aluminum, the casting aluminum rare earth lanthanum alloy liquid is transferred to the electric heating insulation furnace of the casting machine, and the insulation furnace is maintained at a temperature of 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is performed, and the casting pressure is 0.5 atmospheres. Qualified aluminum rare earth lanthanum alloy wheel hub castings are cast, and after heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum rare earth lanthanum alloy wheel hub finished product is obtained. The casting flash and mechanical turning produced in the casting process can be returned to the smelting process.

[0063] Compared with the wheel hub obtained in Example 1, the wheel hub product obtained in this comparative example has a temperature resistance lowered by 6.9%, a wear resistance lowered by 36.4%, a tensile strength lowered by 29.4%, and an elongation lowered by 15.8%.

[0064] Comparative Example 3

[0065] The difference from Example 1 is that only one rare earth element Ce is added during the preparation process, specifically as follows:

[0066] (1) reacting a cerium-containing rare earth compound with aluminum to obtain an aluminum-rare earth Ce master alloy; in the aluminum-Ce master alloy, the weight percentage of the rare earth element Ce is 2%;

[0067] (2) Smelting the ZL101 aluminum alloy at a furnace temperature of 775° C., then transferring it to a refining and heat-insulating gas furnace for refining, adding the aluminum Ce master alloy to react, and obtaining a liquid cast aluminum rare earth Ce alloy, the composition of which is 0.38% Mg, 7.00% Si, 0.12% Fe, 0.10% Cu, 0.10% Mn, 0.10% Zn, 0.14% Ti, 0.03% Sr, and 0.06% Ce. 0.50%, the balance is aluminum, the cast aluminum rare earth Ce alloy liquid is transferred to the electric heating insulation furnace of the casting machine, the insulation furnace is maintained at 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is performed, the casting pressure is 0.5 atmospheres, and qualified aluminum rare earth Ce alloy wheel hub castings are cast. After heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum rare earth Ce alloy wheel hub finished product is obtained. The casting flash and mechanical turning produced in the casting process can be returned to the smelting process.

[0068] Compared with the wheel hub obtained in Example 1, the wheel hub product obtained in this comparative example has a temperature resistance lowered by 15.9%, a wear resistance lowered by 17.5%, a tensile strength lowered by 37.2%, and an elongation lowered by 28.3%.

[0069] Comparative Example 4

[0070] The difference from Example 1 is that only one rare earth element Pr is added during the preparation process, specifically as follows:

[0071] (1) reacting a rare earth compound containing Pr with aluminum to obtain an aluminum rare earth praseodymium master alloy; in the aluminum rare earth Pr master alloy, the weight percentage of the rare earth element Pr is 2%;

[0072] (2) The ZL101 aluminum alloy is melted at a furnace temperature of 775° C., and then transferred to a refining and heat-insulating gas furnace for refining, and the aluminum rare earth Pr master alloy is added for reaction to obtain a liquid casting aluminum rare earth Pr alloy, the composition of which is 0.38% Mg, 7.00% Si, 0.12% Fe, 0.10% Cu, 0.10% Mn, 0.10% Zn, 0.14% Ti, 0.03% Sr, and 0.06% Pr. 0.50%, the balance is aluminum, the cast aluminum rare earth Pr alloy liquid is transferred to the electric heating insulation furnace of the casting machine, the insulation furnace maintains the temperature at 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is carried out, the casting pressure is 0.5 atmospheres, and qualified aluminum rare earth Pr alloy wheel hub castings are cast. After heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum rare earth Pr alloy wheel hub finished product is obtained. The casting flash and mechanical turning produced in the casting process can be returned to the smelting process.

[0073] Compared with the wheel hub obtained in Example 1, the wheel hub product obtained in this comparative example has a temperature resistance lowered by 9.6%, a wear resistance lowered by 39.4%, a tensile strength lowered by 15.9%, and an elongation lowered by 7.6%.

[0074] Comparative Example 5

[0075] The difference from Example 1 is that only one rare earth element Nd is added during the preparation process, specifically as follows:

[0076] (1) reacting a rare earth compound containing Nd with aluminum to obtain an aluminum-rare earth-neodymium master alloy; the weight percentage of the rare earth element neodymium in the aluminum-rare earth-neodymium master alloy is 2%;

[0077] (2) The ZL101 aluminum alloy is melted at a furnace temperature of 775° C., and then transferred to a refining and heat-insulating gas furnace for refining, and the aluminum rare earth Nd master alloy is added for reaction to obtain a liquid cast aluminum rare earth Nd alloy, the composition of which is 0.38% Mg, 7.00% Si, 0.12% Fe, 0.10% Cu, 0.10% Mn, 0.10% Zn, 0.14% Ti, 0.03% Sr, and 0.06% Nd. 0.50%, the balance is aluminum, the cast aluminum rare earth Nd alloy liquid is transferred to the electric heating insulation furnace of the casting machine, and the insulation furnace is maintained at a temperature of 755°C; the mold preheating temperature is 400°C, and the mold spraying temperature is 250°C; differential pressure casting is performed, and the casting pressure is 0.5 atmospheres. Qualified aluminum rare earth Nd alloy wheel hub castings are cast, and after heat treatment (T6), mechanical processing (turning) and testing (quality inspection), surface treatment (painting) and other links, the cast aluminum rare earth Nd alloy wheel hub finished product is obtained. The casting flash and mechanical turning produced in the casting process can be returned to the smelting process.

[0078] Compared with the wheel hub obtained in Example 1, the wheel hub product obtained in this comparative example has a temperature resistance lowered by 16.9%, a wear resistance lowered by 21.8%, a tensile strength lowered by 63.4%, and an elongation lowered by 16.4%.

[0079] It can be seen from the results of Comparative Examples 1 to 5 that in the aluminum rare earth high entropy alloy of the present invention, the five rare earth elements Sc, La, Ce, Pr, and Nd are present in an equal weight ratio or an equal molar ratio, and their synergistic effect overcomes the shortcomings of the combination of one or two rare earth elements, improves the strengthening effect of each rare earth element, plays a cocktail effect, and improves the casting performance and mechanical properties of the aluminum alloy.

[0080] The above description is a detailed description of the preferred feasible embodiments of the present invention, but the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modified changes completed under the technical spirit suggested by the present invention should fall within the patent scope covered by the present invention.

Claims

1. A cast aluminum rare earth high entropy alloy, characterized in that: The raw material components of the cast aluminum rare earth high entropy alloy include: Sc 0.10-0.25%, La 0.10-0.25%, Ce 0.10-0.25%, Pr 0.10-0.25%, Nd 0.10-0.25%, and the balance is aluminum.

2. The cast aluminum rare earth high entropy alloy according to claim 1, characterized in that: The cast aluminum rare earth high entropy alloy comprises: Mg 0.30-0.45%, Si 6.50-7.50%, Fe≤0.12%, Cu≤0.10%, Mn≤0.10%, Zn≤0.10%, Ti0.08-0.20%, Sr 0.01-0.04%, Sc 0.10-0.25%, La 0.10-0.25%, Ce 0.10-0.25%, Pr0.10-0.25%, Nd 0.10-0.25%, and the balance is aluminum.

3. The cast aluminum rare earth high entropy alloy according to claim 1, characterized in that: The cast aluminum rare earth high entropy alloy comprises: Fe≤0.12%, Cu4.5-5.3%, Mn0.6-1.0%, Ti 0.15-0.37%, Sc 0.10-0.25%, La 0.10-0.25%, Ce 0.10-0.25%, Pr 0.10-0.25%, Nd 0.10-0.25%, and the balance is aluminum.

4. The cast aluminum rare earth high entropy alloy according to claim 1, characterized in that: The cast aluminum rare earth high entropy alloy comprises: Fe≤0.12%, Mg 9.5-11.5%, Sc 0.10-0.25%, La 0.10-0.25%, Ce 0.10-0.25%, Pr0.10-0.25%, Nd 0.10-0.25%, and the balance is aluminum.

5. The cast aluminum rare earth high entropy alloy according to claim 1, characterized in that: The cast aluminum rare earth high entropy alloy comprises: Fe≤0.12%, Si 6-8%, Mg 0.1-0.3%, Zn 9.0-13%, Sc 0.10-0.25%, La 0.10-0.25%, Ce0.10-0.25%, Pr 0.10-0.25%, Nd 0.10-0.25%, and the balance is aluminum.

6. The method for preparing a cast aluminum rare earth high entropy alloy according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) reacting a rare earth compound containing Sc, La, Ce, Pr and Nd with an aluminum-containing raw material to obtain an aluminum-rare earth high-entropy master alloy; (2) The cast aluminum alloy material is melted, and the aluminum rare earth high entropy intermediate alloy is added to react to obtain the cast aluminum rare earth high entropy alloy.

7. The method for preparing a cast aluminum rare earth high entropy alloy according to claim 6, characterized in that: In step (1), the weight percentage of rare earth elements in the aluminum rare earth high entropy master alloy is 2-10%.

8. The method for preparing a cast aluminum rare earth high entropy alloy according to claim 6, characterized in that: In step (1), the aluminum-containing raw material is aluminum and / or aluminum alloy.

9. The method for preparing a cast aluminum rare earth high entropy alloy according to claim 6, characterized in that: In step (2), the cast aluminum alloy material is ZL101 aluminum alloy, ZL201 aluminum-copper alloy, ZL301 aluminum-magnesium alloy or ZL401 aluminum-zinc alloy.

10. The use of a cast aluminum rare earth high entropy alloy in the preparation of a wheel hub product as claimed in claim 1, characterized in that: The following steps are involved: The cast aluminum rare earth high entropy alloy liquid is transferred to an electrically heated insulation furnace of a casting machine to be cast into a wheel hub.