CN115386771A - Aluminum alloy material, preparation method thereof and die-casting method of barrier gate transmission structural member - Google Patents

Abstract

The invention provides an aluminum alloy material, a preparation method thereof and a die-casting method of a barrier gate transmission structural member, wherein the aluminum alloy material comprises the following components in percentage by mass: 8.5 to 12.0 percent; fe is less than or equal to 0.25 percent; cu is less than or equal to 0.05 percent; mn:0.5-1.0%; mg:0.3 to 0.7 percent; zn is less than or equal to 0.1 percent; ti:0.01 to 0.3 percent; b is less than or equal to 0.05 percent; cr is less than or equal to 0.1 percent; ce:0.01 to 0.03 percent; la:0.006-0.02%; sr:0.008-0.045%; ga:0.01 to 0.04 percent; p:0.0005 to 0.002%; ca is less than or equal to 0.002%; the seed crystal addition amount is 0.1-1%; impurity elements are less than or equal to 0.15 percent; the balance of Al; P/Ga is less than or equal to 0.05; ce/La:1.2-1.8. The aluminum alloy material provided by the invention is high in toughness and fatigue resistance.

Description

Aluminum alloy material, preparation method thereof and die casting method of barrier gate transmission structural member

Technical Field

The invention belongs to the technical field of die-casting aluminum alloy, and particularly relates to an aluminum alloy material, a preparation method thereof and a die-casting method of a barrier gate transmission structural member.

Background

The electric barrier gate is widely applied to intersections and toll stations of highways, roads, railways, companies, factories, schools and the like. Since the application scenario of the barrier gate determines that frequent rising and falling and even reverse braking are required, the structural member of the transmission mechanism needs to have high strength and bear large torque, and needs to have high toughness and fatigue resistance. In the prior art, two methods are generally adopted to test and check the performance of the device at the same time:

1. and (3) carrying out life test on the assembled whole barrier gate, namely testing the service life of the transmission structural member of the barrier gate by continuously running around the clock. Generally, a low-end requirement is a requirement of 300 to 500 ten thousand times, a medium-end requirement is a requirement of 500 to 1000 ten thousand times, a high-end requirement is a requirement of 1000 ten thousand times, and a barrier gate requirement on a highway is a high-end requirement.

2. Through a hydraulic mode, the middle part of the structural part is subjected to a pressure test, and the loading load required to bear for a transmission structural part with the lowest performance is not lower than 100MPa when the transmission structural part begins to bend and deform, and is not lower than 150MPa when the transmission structural part breaks.

For a plurality of transmission stressed structural members of the barrier gate, in the prior art, the transmission stressed structural members are generally realized by machining after A3 steel is formed by precision casting or machining an A3 forged steel member. When in test, the A3 forged steel piece begins to bend and deform when being loaded to 100MPa, and breaks at 230 MPa; the A3 steel precision casting starts to bend and deform when being loaded to 130MPa, and breaks at 250 MPa. Both of these operational life tests exceeded 1500 ten thousand. Although various indexes of the precision casting or forging method adopting the A3 steel meet the performance requirements, the steel structural part has large overall weight, low production efficiency of precision casting or forging and very high cost.

In order to reduce weight, reduce cost and improve production efficiency, people hope to adopt common aluminum alloy materials to prepare the transmission stressed structural member of the barrier gate, but the common aluminum alloy materials are difficult to meet the requirements of the barrier gate, particularly, the die-casting aluminum alloy has higher production efficiency, but the die-casting aluminum alloy is difficult to have better fatigue resistance due to the characteristics of the forming mode, and when the die-casting aluminum alloy is used as the transmission stressed structural member of the barrier gate, the performance requirements of the barrier gate are difficult to meet. If the A356 aluminum alloy material is broken when being loaded to 120MPa in the test, meanwhile, after the A356 aluminum alloy transmission structural member is installed on the electric barrier gate, the breakage phenomenon of the structural member occurs in 200 ten thousand running tests continuously around the clock. The ADC12 is broken when being loaded to 90MPa, and after the ADC12 aluminum alloy transmission structural member is installed on an electric barrier gate, the phenomenon of breakage occurs when 50 ten thousand running tests are continuously carried out around the clock. It can be seen that the common aluminum alloy in the prior art is difficult to meet the requirements of the barrier gate, and particularly the high-end requirements are more difficult to meet.

The three requirements of pressurization test, more than 1000 ten thousand times of operation after assembly and low production and manufacturing cost are simultaneously met for the high-strength, high-toughness and fatigue-resistant die-casting aluminum alloy material. Therefore, the die-casting aluminum alloy material with high strength, toughness and fatigue resistance, which can be applied to the electric barrier gate, and the die-casting transmission structural component thereof are developed, the requirements of the barrier gate transmission structural component on high strength, toughness and fatigue resistance and long service life are met, and the gate transmission structural component has urgency and wide application prospect.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides an aluminum alloy material with high strength and toughness and better fatigue resistance, a preparation method thereof and a die-casting method of a barrier gate transmission structural member.

The invention provides an aluminum alloy material which comprises the following components in percentage by mass: 8.5 to 12.0 percent; fe: less than or equal to 0.25 percent; cu: less than or equal to 0.05 percent; mn:0.5 to 1.0 percent; mg:0.3-0.7%; zn: less than or equal to 0.1 percent; ti:0.01 to 0.3 percent; b: less than or equal to 0.05 percent; cr: less than or equal to 0.1 percent; ce:0.01 to 0.03 percent; la:0.006-0.02%; sr:0.008-0.045%; ga:0.01 to 0.04 percent; p:0.0005 to 0.002%; ca: less than or equal to 0.002%; pb: less than or equal to 0.1 percent; sn: less than or equal to 0.01 percent; cd: less than or equal to 0.01 percent; adding amount of the submicron-scale aluminum titanium carbon boron seed crystal material: 0.1 to 1 percent; other unavoidable individual impurity elements of 0.05% or less, the sum of the other unavoidable impurity elements: less than or equal to 0.15 percent; the balance of Al; wherein the ratio of P/Ga is less than or equal to 0.05; the ratio of Ce/La is 1.2-1.8.

Preferably, the sub-micron aluminum titanium carbon boron seed crystal material contains seed crystals in a mass percentage of 2-4%.

Preferably, the mass percentage of Si is 9-11%.

Preferably, the mass percentage of P is 0.0006-0.0012%.

Preferably, the ratio P/Ga is between 0.015 and 0.05.

The invention also provides a preparation method of the aluminum alloy material, which comprises the following steps:

s1, adding 91-95% of aluminum ingots and all silicon in the total amount of the aluminum ingots, melting, heating to 800-830 ℃, standing for 30-40 minutes, and purifying and removing slag for the first time;

s2, adding a preheated manganese additive with the mass percent of 50% at the temperature of 800-830 ℃, stirring and melting, then, standing for 10-20 minutes, adding the rest preheated manganese additive with the mass percent of 50% and the rest preheated titanium additive, stirring and melting, and then, standing for 10-20 minutes;

s3, adding aluminum ingots accounting for 5-9% of the total amount of the rest aluminum ingots for melting, adjusting the temperature of the aluminum liquid to 740-760 ℃, and carrying out secondary purification and slag removal;

s4, adopting argon or nitrogen as a carrier gas, adding a granular sodium-free refining agent according to the addition amount of 0.1-0.2% of the total amount of all the added materials for refining and purification, and then carrying out third purification and deslagging;

s5, adding preheated metal magnesium, melting and uniformly stirring, and standing for 5-10 minutes;

s6, adding a preheated intermediate alloy at the temperature of 740-760 ℃, wherein the intermediate alloy contains rare earth Ce and rare earth La, adjusting the Ce/La ratio to be within the range of constraint conditions of 1.2-1.8, melting and uniformly stirring, standing for 10-15 minutes, and degassing for 5-10 minutes by adopting argon or nitrogen;

s7, adding a preheated phosphorus-copper intermediate alloy with the P content of about 8.3% when the temperature is controlled to be 740-760 ℃, adjusting the ratio of P/Ga to be less than or equal to 0.05, and standing for 10-20 minutes after melting;

s8, degassing the aluminum liquid by adopting argon or nitrogen until a sampling inspection pinhole reaches level 1;

s9, uniformly adding the preheated aluminum-strontium intermediate alloy into the furnace when the temperature of the aluminum liquid is 730-750 ℃, standing for 10-20 minutes, degassing the aluminum liquid for 20-30 minutes by adopting argon or nitrogen, and purifying and deslagging for the fourth time;

s10, adding the preheated submicron-grade aluminum titanium carbon boron seed crystal material when the temperature is 720-750 ℃, melting and uniformly stirring, and then, standing for 5-10 minutes, wherein the aluminum liquid is cast at the temperature of 710-750 ℃.

S11, in the casting process, argon or nitrogen is adopted to perform online degassing at the bottom of the filter box through the air brick with the pore diameter of 15-25 mu m.

Preferably, the aluminum liquid is purified and placed for 5 to 10 minutes before each purification and deslagging except for specific regulations.

Preferably, when argon or nitrogen is adopted to degas the aluminum melt in the furnace, the bounce height of the aluminum liquid is less than 15cm, and the air pressure is between 0.15 and 0.25 MPa.

The invention also provides a die-casting method of the barrier gate transmission structural member, wherein the barrier gate transmission structural member is obtained by die-casting the aluminum alloy material as a raw material; the linear shrinkage factor parameter of aluminum liquid solidification considered during the design of the die-casting die cavity is 0.4-0.6%.

Before die casting: controlling the temperature of the aluminum melt to be less than or equal to 780 ℃; degassing the aluminum melt for 20-30 minutes by adopting argon or nitrogen, and removing scum after degassing;

when die casting:

controlling the temperature of die-casting aluminum liquid to be 680-720 ℃; the temperature of the die casting mould is 200-250 ℃.

Preferably, in the die casting: when the Mg content in the die-cast aluminum melt is reduced to be lower than 0.3 percent by mass due to burning loss, metal magnesium needs to be supplemented, and the magnesium content is ensured to be 0.3-0.7 percent by mass;

when the Sr content in the die-cast aluminum melt is reduced to be lower than 0.008% by mass due to burning loss, the aluminum-strontium intermediate alloy needs to be supplemented, and the Sr mass percent is ensured to be 0.008-0.045%.

The aluminum alloy material and the die-casting aluminum alloy material prepared by the preparation method provided by the invention have the advantages of high strength, toughness and fatigue resistance. The material is used for preparing a barrier gate transmission structural member by die casting, can meet the high-end requirement of the barrier gate, and can be suitable for the transmission mechanism structural member of the electric barrier gate of the expressway.

Detailed Description

The technical solutions of the present invention are further described in detail with reference to specific examples so that those skilled in the art can better understand the present invention and can implement the present invention, but the examples are not intended to limit the present invention.

The embodiment of the invention provides an aluminum alloy material, which comprises the following components in percentage by mass: si:8.5 to 12.0 percent; fe: less than or equal to 0.25 percent; cu: less than or equal to 0.05 percent; mn:0.5-1.0%; mg:0.3-0.7%; zn: less than or equal to 0.1 percent; ti:0.01 to 0.3 percent; b: less than or equal to 0.05 percent; cr: less than or equal to 0.1 percent; ce:0.01 to 0.03 percent; la:0.006-0.02%; sr:0.008-0.045%; ga:0.01 to 0.04 percent; p:0.0005 to 0.002%; ca: less than or equal to 0.002%; pb: less than or equal to 0.1 percent; sn: less than or equal to 0.01 percent; cd: less than or equal to 0.01 percent; adding amount of the submicron-scale aluminum titanium carbon boron seed crystal material: 0.1 to 1 percent; the other inevitable impurity elements are less than or equal to 0.05 percent individually, and the total is as follows: less than or equal to 0.15 percent; the balance of Al; wherein the ratio of P/Ga is less than or equal to 0.05; the ratio of Ce/La is 1.2-1.8.

The die-casting aluminum alloy material provided by the embodiment has the following characteristics:

the silicon content is higher, the silicon content is between near eutectic and eutectic, the casting performance of the alloy is excellent, and the fluidity of the aluminum liquid is better.

The contents of iron, copper and zinc are lower, so that the aluminum alloy has good mechanical property and good corrosion resistance.

The relatively high manganese content is beneficial to improving the strength of the material and the heat resistance, and can also solve the problem of die sticking of a metal die easily caused by low iron during die casting. Meanwhile, the eutectic composition and the high manganese content of the silicon also enable the aluminum alloy to have good welding performance and reduce the hot cracking tendency.

Magnesium is a strengthening element in the aluminum alloy, and proper magnesium content contributes to improving the bending strength of the aluminum alloy. However, too high a magnesium content also reduces the toughness, causes an increase in brittleness, decreases the bending strength, and easily deteriorates the fatigue resistance of the transmission structural member, and causes cracks or even breaks under continuous alternating load. In the embodiment, the material is ensured to have better toughness and fatigue resistance through proper magnesium content and proper adding steps.

Proper amount of strontium, rare earth Ce and La is beneficial to metamorphism eutectic silicon, grain refinement and improvement of fatigue resistance. However, the addition of strontium also needs to prevent the increase of the degree of air suction in the preparation process, excessive Ce and La are also easy to generate new rare earth inclusions to influence the purification and performance of the aluminum alloy material, and the proportion of rare earth elements needs to be well controlled and corresponding control measures need to be added in the preparation process.

The submicron-grade aluminum titanium carbon boron seed crystal material can refine an alpha aluminum phase and solve the problems of uneven grain distribution and stress concentration. The grain refinement effect has long-term effect. Meanwhile, the casting defects such as shrinkage porosity, snow spot and the like can be eliminated, and the mechanical property, the processing property and the fatigue resistance are improved.

A small amount of Ti is mainly used to refine the grains.

Ga and P are trace elements, a certain relation exists between the Ga and the P, the constraint conditions between the Ga and the P are well controlled within the control range of the Ga and the P, and the Al-alloy material can play a role in better grain refinement, toughness improvement and fatigue resistance improvement.

The aluminum alloy material provided by the embodiment adopts various modified and refined materials, and comprehensively and interactively plays the integral role of combining the modified and refined materials from multiple aspects.

The aluminum alloy material provided by the embodiment has low contents of Fe, cu and Zn, and the corrosion resistance is better than that of steel and most aluminum alloy grades due to the special preparation process.

The aluminum alloy material provided by the embodiment can meet the requirements of a barrier gate transmission structural member on high strength and toughness and long fatigue-resistant service life, and can be used as a preparation raw material of a structural member of an electric barrier gate transmission mechanism of a highway.

In a preferred embodiment, the sub-micron aluminum titanium carbon boron seed material contains 2-4% by mass of seed.

In a preferred embodiment, the mass percentage of Si therein is 9-11%.

In a preferred embodiment, the mass percentage of P is 0.0006-0.0012%.

In a preferred embodiment, the P/Ga ratio of phosphorus to gallium is between 0.0015 and 0.05.

In a preferred embodiment, an embodiment of the present invention further provides a method for preparing a die-cast aluminum alloy material, including the following steps:

s1, adding 91-95% of aluminum ingots and all silicon in the total amount of the aluminum ingots, melting, heating to 800-830 ℃, standing for 30-40 minutes, and purifying and removing slag for the first time;

s2, adding a preheated manganese additive with the mass percent of 50% at the temperature of 800-830 ℃, stirring and melting, then, standing for 10-20 minutes, adding the rest preheated manganese additive with the mass percent of 50% and the rest preheated titanium additive, stirring and melting, and then, standing for 10-20 minutes;

s3, adding aluminum ingots accounting for 5-9% of the total amount of the rest aluminum ingots for melting, adjusting the temperature of the aluminum liquid to 740-760 ℃, and carrying out secondary purification and slag removal;

s4, adopting argon or nitrogen as a current-carrying gas, adding a granular sodium-free refining agent according to the addition of 0.1-0.2% of the total amount of all the added materials for refining and purification, and then carrying out third purification and deslagging;

s5, adding preheated metal magnesium, melting and uniformly stirring, and standing for 5-10 minutes;

s6, adding a preheated intermediate alloy at the temperature of 740-760 ℃, wherein the intermediate alloy contains rare earth Ce and rare earth La (or intermediate alloy containing Ce, la and other required alloy elements), adjusting the Ce/La ratio to be within the range of constraint conditions of 1.2-1.8, melting and uniformly stirring, standing for 10-15 minutes, degassing for 5-10 minutes by adopting argon or nitrogen, stirring, sampling and inspecting components, and ensuring that the components meet the following requirements: si:8.5 to 12.0 percent; fe: less than or equal to 0.25 percent; cu: less than or equal to 0.05 percent; mn:0.5 to 1.0 percent; mg:0.3 to 0.7 percent; zn: less than or equal to 0.1 percent; ti:0.01 to 0.3 percent; b: less than or equal to 0.05 percent; cr: less than or equal to 0.1 percent; ce:0.01 to 0.03 percent; la:0.006-0.02%; ca: less than or equal to 0.002 percent; pb: less than or equal to 0.1 percent; sn: less than or equal to 0.01 percent; cd: less than or equal to 0.01 percent; other unavoidable individual impurity elements of 0.05% or less, the sum of the other unavoidable impurity elements: less than or equal to 0.15 percent; the balance of Al;

s7, adding a preheated phosphorus-copper intermediate alloy with the P content of about 8.3% when the temperature is controlled to be 740-760 ℃, adjusting the ratio of P/Ga to be less than or equal to 0.05, standing for 10-20 minutes after melting, sampling and inspecting components, and ensuring that the components meet the following requirements: the mass percent of Ga is 0.01-0.04%; the mass percent of P is 0.0005-0.002%;

s8, degassing the aluminum liquid by adopting argon or nitrogen until a sampling inspection pinhole reaches level 1;

s9, when the temperature of the aluminum liquid is 730-750 ℃, uniformly adding the preheated aluminum-strontium intermediate alloy into the furnace, standing for 10-20 minutes, sampling and inspecting components, and ensuring that the components meet the following requirements: sr accounts for 0.008-0.045% by mass, argon or nitrogen is adopted to carry out degassing on the aluminum liquid for 20-30 minutes, and fourth time of purification and deslagging is carried out;

s10, adding the preheated submicron-grade aluminum titanium carbon boron seed crystal material when the temperature is 720-750 ℃, melting and uniformly stirring, and then, standing for 5-10 minutes, wherein the aluminum liquid is cast at the temperature of 710-750 ℃.

S11, in the casting process, argon or nitrogen is adopted to perform online degassing at the bottom of the filter box through a gas permeable brick with the pore diameter of 15-25 mu m. The prepared material composition meets the following conditions:

by mass percent, si:8.5 to 12.0 percent; fe: less than or equal to 0.25 percent; cu: less than or equal to 0.05 percent; mn:0.5-1.0%; mg:0.3-0.7%; zn: less than or equal to 0.1 percent; ti:0.01 to 0.3 percent; b: less than or equal to 0.05 percent; cr: less than or equal to 0.1 percent; ce:0.01 to 0.03 percent; la:0.006-0.02%; sr:0.008-0.045%; ga:0.01 to 0.04 percent; p:0.0005-0.002%; ca: less than or equal to 0.002 percent; pb: less than or equal to 0.1 percent; sn: less than or equal to 0.01 percent; cd: less than or equal to 0.01 percent; adding amount of the submicron aluminum titanium carbon boron seed crystal material: 0.1 to 1 percent; other inevitable individual impurity elements are less than or equal to 0.05%, and the sum of other inevitable impurity elements is as follows: less than or equal to 0.15 percent; the balance being Al.

In the preferred embodiment, except for specific provisions, the aluminum liquid is purified and placed for 5-10 minutes before each purification and deslagging.

In the preferred embodiment, when argon or nitrogen is used for degassing the aluminum melt in the furnace, the bounce height of the aluminum liquid is less than 15cm, and the air pressure is between 0.15 and 0.25 MPa.

The invention also provides a die-casting method of the barrier gate transmission structural member, wherein the barrier gate transmission structural member is obtained by die-casting the aluminum alloy material as a raw material; the linear shrinkage factor parameter of aluminum liquid solidification considered during the design of the die-casting die cavity is 0.4-0.6%.

Before die casting:

controlling the temperature of the aluminum melt to be less than or equal to 780 ℃; degassing the aluminum melt for 20-30 minutes by adopting argon or nitrogen, and removing scum after degassing;

during die casting:

controlling the temperature of the die casting aluminum liquid to be 680-720 ℃, and controlling the lower limit of the thicker wall thickness and the upper limit of the thinner wall thickness of the die casting.

Controlling the temperature of the die casting die at 200-250 ℃, wherein the lower limit of the die casting piece is thicker in wall thickness, and the upper limit of the die casting piece is thinner in wall thickness.

When the Mg content in the die-cast aluminum melt is reduced to be lower than 0.3 percent by mass due to burning loss, metal magnesium needs to be supplemented, and the mass percent of the magnesium is ensured to be 0.3-0.7 percent;

when the Sr content in the die-cast aluminum melt is reduced to be lower than 0.008% by mass due to burning loss, the aluminum-strontium intermediate alloy needs to be supplemented, and the Sr mass percent is ensured to be 0.008-0.045%.

In the process of die casting, no cold materials such as return materials and the like are put into the furnace, so that the air suction of the melt and the increase of impurities are avoided.

If an iron tool is used, the coating needs to be dried to prevent the iron increase and air suction of the aluminum melt in the die casting process.

In order that the technical solutions of the present invention may be further understood and appreciated, several preferred embodiments are now described in detail.

Barrier gate transmission structural members of examples 1 to 5 and comparative examples 1 to 17 were prepared according to the materials and the molding methods in table 1, respectively.

TABLE 1

The die-cast aluminum alloy material 1 in table 1 is prepared as follows:

the formula of the prepared die-casting aluminum alloy material is as follows:

si:10.1 percent; fe:0.09%; cu:0.002%; mn:0.654 percent; mg:0.38 percent; zn:0.03 percent; ti:0.012%; b:0.012%; cr:0.02 percent; ce:0.015 percent; la:0.011 percent; sr:0.0346%; ga:0.03 percent; p:0.001 percent; ca:0.0006 percent; pb:0.002; sn:0.001 percent; cd:0.001 percent; adding amount of the submicron-scale aluminum titanium carbon boron seed crystal material: 0.25 percent; the other inevitable impurity elements are less than or equal to 0.05 percent individually, and the total is as follows: less than or equal to 0.15 percent; the balance of Al. Wherein Ce/La was 1.36 and P/Ga was 0.033.

The specific method comprises the following steps:

(1) After addition of 93% of the quantity of aluminum ingot and the total amount of silicon, the mixture was melted and warmed to 820 ℃ and allowed to stand for 35 minutes.

(2) And carrying out first purification and deslagging.

(3) Adding preheated 50% manganese additive at 820 deg.C, stirring to melt, and standing for 15 min.

(4) Then adding the rest preheated 50 percent of manganese additive and titanium additive, stirring and melting, and then standing for 15 minutes.

(5) The remaining 7% of the quantity of aluminum ingot was added and melted.

(6) Adjusting the temperature of the aluminum liquid to 750 ℃.

(7) And (5) placing the aluminum liquid for 8 minutes for secondary purification and deslagging.

(8) Argon or nitrogen is used as carrier gas, and a granular sodium-free refining agent is added according to the addition of 0.15 percent for refining and purification.

(9) And (5) placing the aluminum liquid for 8 minutes for third purification and deslagging.

(10) Adding preheated magnesium metal, melting and stirring uniformly, and standing for 10 minutes.

(11) And (3) controlling the temperature at 750 ℃, adding the preheated intermediate alloy containing rare earth Ce and the preheated intermediate alloy containing rare earth La, and adjusting the ratio Ce/La to meet the condition. Melting, stirring uniformly, and standing for 10 minutes.

(12) Argon or nitrogen is used for degassing for 10 minutes, the bounce height of the aluminum liquid is less than 15cm during degassing, and the air pressure is between 0.15 and 0.25 MPa.

(13) Stirring, sampling and inspecting the components.

(14) Adding preheated phosphorus-copper intermediate alloy with P content of about 8.3% at 750 ℃, and adjusting the proportion of P/Ga to meet the constraint condition. After melting, the mixture was allowed to stand for 15 minutes.

(15) Stirring, sampling and inspecting the components.

(16) When the components except Sr are qualified, argon or nitrogen is adopted to degas the aluminum liquid, and when the components except Sr are degassed, the bounce height of the aluminum liquid is less than 15cm, and the air pressure is between 0.15 and 0.25 MPa. Until the sampling inspection pinhole reaches grade 1.

(17) And uniformly adding the preheated aluminum-strontium intermediate alloy into the furnace when the temperature of the aluminum liquid is 740 ℃, and standing for 15 minutes.

(18) Stirring, sampling and inspecting the components.

(19) And degassing the aluminum liquid for 25 minutes by adopting argon or nitrogen, wherein the bounce height of the aluminum liquid is less than 15cm and the air pressure is between 0.15 and 0.25MPa during degassing.

(20) And (5) the aluminum liquid is kept for 8 minutes for fourth purification and deslagging.

(21) The preheated submicron order aluminum titanium carbon boron seed material (containing 2-4% of seed) is added at the temperature of 740 ℃. Melting and stirring evenly, and standing for 8 minutes.

(22) And casting the molten aluminum at the temperature of 720 ℃.

(23) In the casting process, nitrogen is adopted to perform online degassing at the bottom of the filter box through a gas permeable brick with the pore diameter of 15-25 mu m.

The production methods of comparative materials 1 to 10 in table 1 are different from those of die-cast aluminum alloy material 1 in the points listed in table 2, and the remaining formulations and production methods are the same as those of die-cast aluminum alloy material 1.

TABLE 2

The die-casting method indicated in table 1 is:

and melting the aluminum alloy material, and then forming the aluminum alloy material by a die casting machine at high pressure and high speed to obtain the barrier gate transmission structural member, wherein the selection of the aluminum liquid solidification linear shrinkage factor parameter considered during the design of a die casting die cavity is 0.5%.

Before die casting: the temperature of the aluminum melt (remelting temperature) is less than or equal to 780 ℃; the aluminum melt was degassed with argon or nitrogen for 15 minutes. And removing scum after degassing.

During die casting: the temperature of the aluminum liquid is 700 ℃; the temperature of the die-casting die is 200 ℃.

And preparing the F-state barrier gate transmission structural member by die casting.

The precision casting method indicated in table 1 is: the A3 steel is subjected to precision investment casting.

The steel forging method indicated in table 1 is: the A3 steel adopts a die forging method.

The semi-solid die casting method referred to in table 1 is: a356 aluminum melt with the temperature between liquid and solid phases is molded by rheologic die casting.

The state "F" indicated in table 1 is: the natural state of the workpiece after forming.

The state "T4" indicated in table 1 is: after the workpiece is formed, the solution treatment and natural aging are carried out.

The state "T5" indicated in table 1 is: and performing artificial aging treatment on the formed workpiece.

The state "T6" referred to in table 1 is: after the workpiece is formed, the workpiece is subjected to solid solution treatment and artificial complete aging treatment.

The state "T7" indicated in table 1 is: after the workpiece is formed, the workpiece is subjected to solid solution treatment and artificial overaging treatment.

After the barrier gate transmission structural members obtained in examples 1 to 5 and comparative examples 1 to 17 were mounted, a press bending and press breaking test was performed.

1. The bending and breaking test method comprises the following steps: and (3) carrying out a pressure test on the middle part of the structural part in a hydraulic mode, wherein the load borne by the structural part is the load when the structural part starts to bend, deform and break. The general barrier gate transmission structural member is required to be not less than 100MPa in bending deformation and not less than 150MPa in fracture.

2. And carrying out fatigue resistance test on the assembled whole barrier gate, and continuously running day and night to test the service life of the structural member of the transmission mechanism. The fatigue test requirement of the barrier gate transmission structural member of the expressway reaches more than 1000 ten thousand times.

3. The method for calculating the production and manufacturing cost coefficient comprises the following steps: since the specific production and manufacturing costs are affected by price fluctuations of materials, processes, and the like at different time intervals, comparison of absolute values is difficult to reasonably reflect the difference comparison between the materials and the processes. The cost of precision casting of A3 steel with the highest production and manufacturing cost in the same time period is taken as a coefficient 1, and the rest production and manufacturing costs are compared with the coefficient to obtain respective production and manufacturing cost coefficients so as to carry out relative comparison and reasonably reflect the relative difference proportion between the two.

The test results are shown in table 3.

TABLE 3

In summary, and in combination with table 1, it can be seen that the barrier gate transmission structural member prepared in embodiments 1 to 5 of the present invention can satisfy the pressurization performance test requirements in 5 different states.

After the barrier gate transmission structural member prepared in the embodiments 1-5 of the invention is assembled on a transmission mechanism of a barrier gate, the barrier gate can continuously run around the clock for more than 1500 ten thousand times and still normally run, the transmission structural member is not deformed, broken and seriously worn, and the high-end application requirement of a highway for more than 1000 ten thousand times is met. And the production efficiency is higher, the production cost is lower, and especially the F state has the advantage of production and manufacturing cost.

In comparative examples 1 to 7, after the components of the die-cast aluminum alloy material are changed, the die-cast aluminum alloy material does not meet the formula requirements, or does not meet the constraint conditions, or is added with a small amount of certain additives, the bending and breaking performance is reduced to different degrees, although the die-cast aluminum alloy material still meets the requirements of the test indexes, the operation life test only meets the requirements of the middle-end application indexes, and does not meet the requirements of high-end application.

In comparative examples 8 to 10, although the composition of the aluminum alloy material was satisfactory, the process requirements for the production were changed, the press bending and press breaking properties were decreased to various degrees, and although the test index was still satisfied, the operation life test was only as satisfactory as the middle-end application index, and was not satisfactory as the high-end application index.

In comparative examples 11 to 12, the precision casting or forging method of A3 steel was used, and all the indexes met the performance requirements, but the production efficiency was low, the manufacturing cost was high, and particularly the precision casting cost was the highest. The manufacturing cost of the embodiment 1-5 of the invention is lower, about 1/3 of the precision casting of A3 steel, and the die-casting forming mode can be used, so that the production efficiency is higher.

In comparative example 13, ADC12 was used as a die casting raw material, and each index property was very poor.

In comparative examples 14 to 17, a356 aluminum alloy material was used as a raw material, which had better performance than ADC12, and especially achieved the index requirements through the semi-solid die-casting bending and breaking performance tests, but had relatively low fatigue resistance, the operation life test only achieved the low-end application index, the index differed from the high-end application index, and the manufacturing cost of semi-solid die-casting was relatively high.

In summary, the invention provides a die-casting aluminum alloy material which can be used as a structural member for producing a highway barrier gate transmission mechanism, can meet the requirements of the barrier gate transmission structural member on high strength and toughness and long fatigue-resistant service life, and compared with the originally used precision cast steel or forged steel, the die-casting aluminum alloy has lighter weight, lower manufacturing cost and higher production efficiency.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and all equivalent structures or equivalent processes, which can be directly or indirectly applied to other related technical fields, are encompassed by the present invention.

Claims (10)

1. An aluminum alloy material, characterized by comprising, in mass percent, si:8.5 to 12.0 percent; fe: less than or equal to 0.25 percent; cu: less than or equal to 0.05 percent; mn:0.5-1.0%; mg:0.3-0.7%; zn: less than or equal to 0.1 percent; ti:0.01 to 0.3 percent; b: less than or equal to 0.05 percent; cr: less than or equal to 0.1 percent; ce:0.01 to 0.03 percent; la:0.006-0.02%; sr:0.008-0.045%; ga:0.01 to 0.04 percent; p:0.0005 to 0.002%; ca: less than or equal to 0.002%; pb: less than or equal to 0.1 percent; sn: less than or equal to 0.01 percent; cd: less than or equal to 0.01 percent; adding amount of the submicron-scale aluminum titanium carbon boron seed crystal material: 0.1 to 1 percent; other inevitable individual impurity elements are less than or equal to 0.05%, and the sum of other inevitable impurity elements is as follows: less than or equal to 0.15 percent; the balance of Al; wherein the ratio of P/Ga is less than or equal to 0.05; the ratio of Ce/La is 1.2-1.8.

2. The aluminum alloy material of claim 1, wherein the sub-micron aluminum titanium carbon boron seed material comprises from 2 to 4% by mass of seeds.

3. The aluminum alloy material according to claim 1, wherein the Si is 9 to 11% by mass.

4. The aluminum alloy material according to claim 1, wherein the mass percentage of P is 0.0006 to 0.0012%.

5. An aluminium alloy material according to claim 1, wherein the ratio P/Ga is in the range of 0.015-0.05.

6. The method of producing an aluminum-alloy material according to any one of claims 1 to 5, comprising the steps of:

s1, adding aluminum ingots accounting for 91-95% of the total amount of the aluminum ingots and all silicon, then melting, heating to 800-830 ℃, standing for 30-40 minutes, and purifying and removing slag for the first time;

s2, adding a preheated manganese additive with the mass percent of 50% at the temperature of 800-830 ℃, stirring and melting, standing for 10-20 minutes, adding the rest preheated manganese additive and titanium additive with the mass percent of 50%, stirring and melting, and standing for 10-20 minutes;

s3, adding 5-9% of aluminum ingots in the total amount of the rest aluminum ingots for melting, adjusting the temperature of aluminum liquid to 740-760 ℃, and carrying out secondary purification and slag removal;

s4, adopting argon or nitrogen as a carrier gas, adding a granular sodium-free refining agent according to the addition of 0.1-0.2% of the total amount of all the added materials for refining and purification, and then carrying out third purification and deslagging;

s5, adding preheated metal magnesium, melting and uniformly stirring, and standing for 5-10 minutes;

s6, adding a preheated intermediate alloy at the temperature of 740-760 ℃, wherein the intermediate alloy contains rare earth Ce and rare earth La, adjusting the Ce/La ratio to be within the range of the constraint condition of 1.2-1.8, melting and uniformly stirring, standing for 10-15 minutes, and degassing for 5-10 minutes by adopting argon or nitrogen;

s7, adding a preheated phosphorus-copper intermediate alloy with the P content of about 8.3% when the temperature is controlled to be 740-760 ℃, adjusting the ratio of P/Ga to be less than or equal to 0.05, and standing for 10-20 minutes after melting;

s8, degassing the aluminum liquid by adopting argon or nitrogen until a sampling inspection pinhole reaches level 1;

s9, uniformly adding the preheated aluminum-strontium intermediate alloy into the furnace when the temperature of the aluminum liquid is 730-750 ℃, standing for 10-20 minutes, degassing the aluminum liquid for 20-30 minutes by adopting argon or nitrogen, and purifying and deslagging for the fourth time;

s10, adding a preheated submicron aluminum titanium carbon boron seed crystal material at the temperature of 720-750 ℃, melting and uniformly stirring, and then, standing for 5-10 minutes, wherein the aluminum liquid is cast at the temperature of 710-750 ℃;

s11, in the casting process, argon or nitrogen is adopted to perform online degassing at the bottom of the filter box through the air brick with the pore diameter of 15-25 mu m.

7. The method for producing an aluminum alloy material according to claim 6, wherein the aluminum liquid is purified for 5 to 10 minutes before each purification and deslagging except for specific provisions.

8. The method for preparing an aluminum alloy material according to claim 6, wherein when degassing is performed on the aluminum melt in the furnace by using argon or nitrogen, the bounce height of the aluminum liquid is less than 15cm, and the air pressure is between 0.15 and 0.25 MPa.

9. The pressure casting method of the barrier gate transmission structural member is characterized in that the barrier gate transmission structural member is obtained by pressure casting by using the aluminum alloy material of claims 1-5 as a raw material; the solidification linear shrinkage factor parameter of the aluminum liquid considered when the die-casting die cavity is designed is 0.4-0.6%;

before die casting: controlling the temperature of the aluminum melt to be less than or equal to 780 ℃; degassing the aluminum melt for 20-30 minutes by adopting argon or nitrogen, and removing scum after degassing;

when die casting:

controlling the temperature of die-casting aluminum liquid to be 680-720 ℃; the temperature of the die casting mold is 200-250 ℃.

10. The method for die-casting a barrier gate transmission structural member according to claim 9, wherein during die-casting: when the Mg content in the die-cast aluminum melt is reduced to be lower than 0.3 percent by mass due to burning loss, metal magnesium needs to be supplemented, and the mass percent of the magnesium is ensured to be 0.3-0.7 percent;

when the Sr content in the die-cast aluminum melt is reduced to be lower than 0.008% by mass due to burning loss, the aluminum-strontium intermediate alloy needs to be supplemented, and the Sr mass percent is ensured to be 0.008-0.045%.