AlSi7Cu0. 5Mg alloy for high-performance casting of automobile engine and production process of AlSi7Cu0. 5Mg alloy

Abstract

The invention discloses an Al Si7Cu0. 5Mg alloy for high-performance casting of an automobile engine and a production process of the Al Si7Cu0. 5Mg alloy, and relates to the technical field of aluminum alloys. The alloy is composed of, by mass, 6.5%-7.5% of silicon, smaller than or equal to 0.15% of iron, 0.48%-0.55% of copper, 0.05%-0.10% of manganese, 0.37%-0.45% of magnesium, 0.10%-0.15% of titanium, 0.015%-0.020% of strontium, smaller than or equal to 0.07% of zinc and the balance aluminum, and impurities contained in the alloy are smaller than 0.3%. The content of the element magnesium is reduced, and the harmful effect of the element magnesium on the toughness and thermal stability of the alloy is reduced; the content of silicon is adjusted, and the casting performance and the cutting performance of the alloy are improved; through strontium modification, the alloy has high density, and the strength and toughness of the alloy are improved; by adding the titanium element, the alloy strength and the higher high-temperature-resistant effect are improved, and an alloy ingot prepared from the alloy has excellent casting performance, mechanical performance, physical performance, corrosion resistance and machining performance; the production process is simple, the process is simple and efficient, and mass production is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum alloys, and in particular to an AlSi7Cu0.5Mg alloy used for high-performance casting of automobile engines and a production process thereof. Background Art

[0002] Aluminum alloy is an alloy material widely used in industry. Aluminum element is combined with other elements to derive a variety of aluminum alloy materials, such as aluminum-silicon alloy, aluminum-magnesium alloy, aluminum-zinc alloy, etc. Due to the excellent performance of aluminum alloy, it has been rapidly developed in various industries. Now aluminum alloy plays an important role in aerospace, construction, and automobiles.

[0003] In the automotive industry, aluminum alloys are widely used. Various aluminum alloys are needed from car bumpers, bodies to engines. In the production of automobile engines, aluminum alloy engines have been developed, which have the advantages of light weight and reduced fuel consumption. Automobile engines are the core components of automobiles, and conventional aluminum alloys cannot meet the use conditions. This paper proposes a high-performance alloy material for manufacturing automobile engines. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide an AlSi7Cu0.5Mg alloy for high-performance casting of automobile engines and its production process, and to propose an aluminum-silicon-magnesium-copper alloy with good mechanical properties, high strength, light weight, and good heat resistance. The casting structure made of the aluminum-silicon-magnesium-copper alloy has high strength and long service life.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions: an AlSi7Cu0.5Mg alloy for high-performance casting of automobile engines, the alloy is composed of the following components in mass percentage: silicon: 6.5-7.5%, iron: ≤0.15%, copper: 0.48-0.55%, manganese: 0.05-0.10%, magnesium: 0.37-0.45%, titanium: 0.10-0.15%, strontium: 0.015-0.020%, zinc: ≤0.07%, and the rest is aluminum, and the impurities contained in the alloy are less than 0.3%.

[0006] The present invention is further provided as follows: a production process of AlSi7Cu0.5Mg alloy, comprising the following steps:

[0007] Step 1: material smelting: first, aluminum, magnesium, zinc, iron, copper, manganese, silicon, titanium and strontium are put into a metal melting furnace according to the mass percentage for smelting, and the temperature in the metal melting furnace is adjusted to melt and preliminarily mix the above components to obtain a first metal solution;

[0008] Step 2: uniform treatment, stirring the obtained first metal solution by ultrasonic or electromagnetic waves to make it uniformly mixed, so as to obtain a second metal solution;

[0009] Step 3: Casting: input the second molten metal into a vacuum casting machine, and obtain an alloy ingot through vacuum suction casting of the vacuum casting machine;

[0010] Step 4: Workpiece production: the obtained alloy ingots are made into high-performance parts for automobile engines.

[0011] The present invention is further configured as follows: in the step one, aluminum is first added to a metal melting furnace, the temperature of the metal melting furnace is increased to 770-910°C, the aluminum is melted into aluminum liquid, magnesium, zinc, and strontium are then added to the aluminum liquid to obtain an aluminum-magnesium alloy solution, the temperature in the metal melting furnace is increased to 1800-2000°C, powdered titanium, silicon, manganese, copper, and iron are added to the aluminum liquid in sequence, and after melting, an aluminum-silicon-magnesium-copper alloy solution constituting the first metal solution is obtained.

[0012] The present invention is further configured as follows: in the step 2, the temperature in the metal melting furnace is adjusted to 760-780°C, and after standing for 10-30 minutes, the first molten metal is stirred by ultrasound or electromagnetic waves to form a fully mixed second metal solution, and the frequency of the ultrasound is 35kHz-80kHz.

[0013] The present invention is further configured as follows: in the step three, the vacuum casting device used is connected to the metal melting furnace, and the second molten metal in the metal melting furnace can be directly input into the vacuum casting device. The vacuum casting device includes a machine base and a machine body installed on the machine base. The bottom of the machine base has a bottom plate, and the bottom plate has an extension section. The metal melting furnace is arranged on the extension section. The metal melting furnace has a feed port. A PLC controller is arranged in the machine base, and the PLC controller is used to control the vacuum casting device and the metal melting furnace.

[0014] The present invention is further configured as follows: the body includes an outer shell and a vacuum chamber, the vacuum chamber is located inside the outer shell, the outer shell is provided with a plurality of pipes communicating with the vacuum chamber, the outer shell is provided with a sealing door, one end of the sealing door is hinged to the outer shell, and the outer shell is also provided with a locking member for locking the sealing door, the locking member is hinged to the outer shell, a hand wheel is provided on the locking member, and the sealing door is provided with an observation window.

[0015] The present invention is further configured as follows: sealing members are respectively provided on the surfaces opposite to the sealing door, the sealing members are a receiving member arranged on the housing and a plug-in member arranged on the sealing door, the receiving member is annular, the receiving member has a receiving groove, the receiving member is made of high-temperature resistant silicone rubber, and its Shore hardness is 28-35, the plug-in member is "T"-shaped, and its protruding part faces the receiving groove, the plug-in member is adhered to the sealing door, and the plug-in member is made of high-temperature resistant silicone rubber with a Shore hardness of 28-35. When in use, it moves synchronously with the sealing door and is then inserted into the receiving groove.

[0016] The present invention is further configured as follows: the pipeline includes a feed pipe, a discharge pipe, an air inlet pipe and an air outlet pipe, the feed pipe and the discharge pipe are arranged on two sides of the shell opposite to each other, the feed pipe is connected to the metal melting furnace, the discharge pipe is used to send out the alloy ingots, the air inlet pipe and the air outlet pipe are both arranged on the top of the shell, the air inlet pipe is used to inject inert gas into the vacuum chamber, the air outlet pipe is used to evacuate the vacuum chamber, and a pressure sensor is also provided on the shell on one side of the air inlet pipe, and at least a portion of the pressure sensor extends into the vacuum chamber.

[0017] In summary, the present invention has the following beneficial effects: the content of elemental magnesium is reduced, thereby reducing its harmful effects on the toughness and thermal stability of the alloy; the content of silicon is adjusted, thereby improving the casting performance and cutting performance of the alloy; and the alloy is modified by strontium to give the alloy a higher density, thereby improving the strength and toughness of the alloy; the addition of titanium element improves the strength of the alloy and a higher high temperature resistance effect, and the alloy ingot prepared by the above-mentioned method has excellent casting performance, mechanical properties, physical properties, corrosion resistance and machining performance; the production process is simple, the process is concise and efficient, and is conducive to mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of the vacuum casting device of the present invention;

[0019] Figure 2 It is a schematic diagram of the vacuum chamber structure of the present invention;

[0020] Figure 3 It is a process flow chart of the present invention.

[0021] In the figure: 1. metal melting furnace; 2. vacuum casting device; 3. machine base; 31. bottom plate; 4. machine body; 5. vacuum chamber; 51. forming mold; 6. shell; 7. feed pipe; 8. discharge pipe; 9. air inlet pipe; 10. air outlet pipe; 11. sealing door; 12. observation window; 13. locking piece; 14. hand wheel; 15. sealing piece. DETAILED DESCRIPTION

[0022] The present invention is described in detail below in conjunction with the accompanying drawings and embodiments.

[0023] The present invention discloses an AlSi7Cu0.5Mg alloy for high-performance casting of automobile engines. The alloy has good casting performance and physical properties and can be used for casting automobile engines. The alloy is composed of the following components in mass percentage: silicon: 6.5-7.5%, iron: ≤0.15%, copper: 0.48-0.55%, manganese: 0.05-0.10%, magnesium: 0.37-0.45%, titanium: 0.10-0.15%, strontium: 0.015-0.020%, zinc: ≤0.07%, and the rest is aluminum. The impurities contained in the alloy are less than 0.3%. The magnesium element can generate a strengthening phase with the aluminum element and the silicon element in the aluminum alloy material, play a role of solid solution strengthening, and thus improve the strength of the aluminum alloy material. Based on this, the silicon element and the magnesium element play the same role. In addition to generating CuAl2 aging strengthening with the aluminum element, the copper element also has a good solid solution Strengthening effect to improve the strength of aluminum alloy materials; manganese elements generate MnAl6 compounds with aluminum elements in aluminum alloy materials, which can effectively prevent the problem of grain growth during recrystallization of aluminum alloy materials, thereby significantly refining recrystallized particles; titanium elements only need a small content in aluminum alloy materials to improve their mechanical properties; strontium elements can improve the plasticity of alloys. Through modification, strontium can change the phase behavior of intermetallic compounds, thereby improving the plasticity of aluminum alloys, making the alloys easier to form and process, and can also improve mechanical properties. Adding an appropriate amount of strontium to aluminum alloys can significantly improve the mechanical properties of the alloys, such as tensile strength and yield strength, while increasing elongation; zinc elements will generate strengthening phases in aluminum alloy materials, improving the yield strength and tensile strength of aluminum alloy materials; based on this, the alloy ingots made using the above-mentioned component ratios have excellent casting properties, mechanical properties, physical properties, corrosion resistance and machining properties.

[0024] like Figure 3 As shown, according to the embodiment of the present application, a production process of AlSi7Cu0.5Mg alloy is also provided, which can be used to prepare the aluminum alloy material of the above scheme, comprising the following steps:

[0025] Step 1: material smelting: first, aluminum, magnesium, zinc, iron, copper, manganese, silicon, titanium and strontium are put into a metal melting furnace 1 according to mass percentage for smelting, and the temperature in the metal melting furnace 1 is adjusted to melt and preliminarily mix the above components to obtain a first metal solution;

[0026] Step 2: uniform treatment, stirring the obtained first metal solution by ultrasonic or electromagnetic waves to make it uniformly mixed, so as to obtain a second metal solution;

[0027] Step 3: Casting: input the second molten metal into a vacuum casting machine, and obtain an alloy ingot through vacuum suction casting of the vacuum casting machine;

[0028] Step 4: Workpiece production: the obtained alloy ingot is made into high-performance parts for automobile engines;

[0029] The metal melting furnace 1 is used to melt and mix the raw materials of each component. During the preparation, aluminum is first added to the metal melting furnace 1, and the temperature of the metal melting furnace 1 is increased to 770-910°C, preferably 820°C, so that the aluminum is melted into aluminum liquid, and then magnesium, zinc, and strontium are added to the aluminum liquid to obtain an aluminum-magnesium alloy solution. The temperature in the metal melting furnace 1 is increased to 1800-2000°C, which can melt the following metals with higher melting points, and powdered titanium, silicon, manganese, copper and iron are added to the aluminum liquid in sequence. After melting, an aluminum-silicon-magnesium-copper alloy solution is obtained, and the temperature in the metal melting furnace 1 is reduced to 760-780°C, preferably 760°C, and it is allowed to stand for 10-30 minutes, and the temperature is continued as the standing time increases. The temperature in the metal melting furnace 1 is lowered. After at least 20 minutes, the temperature in the metal melting furnace 1 will reach 700°C. The aluminum-silicon-magnesium-copper alloy solution is shaken and stirred by ultrasonic technology. The ultrasonic frequency used is 35kHz-80kHz, so that the solutions of each component are evenly mixed to obtain a second metal solution for casting. The evenly mixed second metal solution is then transported to a vacuum casting device 2. The second metal solution is cast into shape by the vacuum casting device 2 to obtain an alloy ingot. Finally, the alloy ingot is used to manufacture an automobile engine or related parts on the engine. The alloy ingot made by the above method is light in weight, high in strength, has good mechanical properties and high temperature resistance, and is beneficial to improving the service life of the automobile engine.

[0030] like Figure 1 As shown, the vacuum casting device 2 provided by the present invention is used to make an alloy ingot from a second metal solution. The vacuum casting device 2 includes a machine base 3 and a machine body 4. The machine base 3 is provided with a bottom plate 31, and the bottom plate 31 is used to support the machine base 3 and the metal melting furnace 1. The lower end surface of the bottom plate 31 is provided with a plurality of supporting feet. The machine base 3 is installed on one side of the upper end surface of the bottom plate 31, and the metal melting furnace 1 is installed opposite to it on the other side of the upper end surface of the bottom plate 31, and the metal melting furnace 1 is connected to the vacuum casting device 2. The machine base 3 is used to install electrical equipment, such as a PLC controller for controlling the vacuum casting device 2 and the metal melting furnace 1.

[0031] Specifically, Figure 1 , Figure 2As shown, the machine body 4 is installed at the upper end of the machine base 3, and the machine body 4 is composed of an outer shell 6 and a vacuum chamber 5 enclosed in the inner part of the outer shell 6. A plurality of pipes are arranged on the outer shell 6, and the plurality of pipes are communicated with the vacuum chamber 5; specifically, the plurality of pipes are a feed pipe 7, a discharge pipe 8, an air inlet pipe 9 and an air outlet pipe 10, and the feed pipe 7 and the discharge pipe 8 are arranged on both sides of the outer shell 6 opposite to each other, the feed pipe 7 is connected to the metal melting furnace 1, the discharge pipe 8 is used to send out the alloy ingot, the air inlet pipe 9 and the air outlet pipe 10 are both arranged on the top of the outer shell 6, the air inlet pipe 9 is used to inject inert gas into the vacuum chamber 5, and the air outlet pipe 10 is used to evacuate the vacuum chamber 5, and a pressure sensor is also arranged on the shell on one side of the air inlet pipe 9, and at least a part of the pressure sensor extends into the vacuum chamber 5, and a forming mold 51 is also arranged in the vacuum chamber 5, and the vacuum chamber 5 uses the forming mold 51 to form the second metal solution into an alloy ingot by vacuum suction casting.

[0032] like Figure 1 , Figure 2 As shown, a sealing door 11 is further provided at one end of the housing 6, one end of the sealing door 11 is hinged to one side of the housing 6, the sealing door 11 is semicircular, and an observation window 12 is further provided on the sealing door 11, and the observation window 12 is used to observe the situation in the vacuum chamber 5 from the outside, and a locking member 13 is further provided on the other side of the housing 6, and at least a part of the locking member 13 is hinged to the housing 6, and the locking member 13 is "L" shaped, and the bent part of the locking member 13 is clamped on the sealing door 11, and the locking member 13 is also provided There is a hand wheel 14 that runs through its thickness. When the sealing door 11 is closed, the hand wheel 14 is tightened so that the rod running through the hand wheel 14 is squeezed on the sealing door 11 to strengthen the sealing between the sealing door 11 and the shell 6; and sealing members 15 are respectively provided on the opposite surfaces of the sealing door 11 and the shell 6. The sealing member 15 includes a plug-in member arranged on the sealing door 11 and a receiving member arranged on the shell 6. The plug-in member and the receiving member are both made of high-temperature resistant silicone rubber with a Shore hardness of 28-35. The receiving member is annular and is adhered to the shell 6 by high-temperature resistant glue, or fastened by bolts. After the receiving member is installed in place, a recessed receiving groove is provided on the side facing the sealing door 11. The plug-in member is fixed to the side of the sealing door 11 facing the shell 6 by high-temperature resistant glue or bolts. The plug-in member is annular and has a "T"-shaped cross-sectional structure. After the installation is completed, the convex part of the plug-in member faces the receiving groove. When in use, the plug-in member moves synchronously with the sealing door 11. When the vacuum chamber 5 needs to be sealed When sealing, the sealing door 11 is closed, the connector is inserted into the receiving part, specifically, the raised part of the connector is inserted into the receiving groove, and then the locking piece 13 is rotated to the front of the sealing door 11, and the locking piece 13 buckles the edge of one side of the sealing door 11 with a part of the shell 6, and finally the hand wheel 14 is tightened, and the rod of the hand wheel 14 is tightly pressed on the sealing door 11, so that the sealing door 11 and the shell 6 are sealed. The sealing door 11 is opened, and the hand wheel 14 is rotated in the reverse direction to make the rod of the hand wheel 14 separate from the sealing door 11.

[0033] In summary, the present invention reduces the harmful effects of elemental magnesium on the toughness and thermal stability of the alloy by reducing the content of elemental magnesium; adjusts the content of silicon to improve the casting performance and cutting performance of the alloy; and through strontium modification, the alloy has a higher density, thereby improving the strength and toughness of the alloy; the addition of titanium element improves the strength of the alloy and higher high temperature resistance. The alloy ingot prepared by the above has excellent casting performance, mechanical properties, physical properties, corrosion resistance and machining performance; the production process is simple, the process is concise and efficient, and is conducive to mass production.

[0034] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. An AlSi7Cu0.5Mg alloy for high performance casting of automobile engines, characterized in that: The alloy is composed of the following components in percentage by mass: silicon: 6.5-7.5%, iron: ≤0.15%, copper: 0.48-0.55%, manganese: 0.05-0.10%, magnesium: 0.37-0.45%, titanium: 0.10-0.15%, strontium: 0.015-0.020%, zinc: ≤0.07%, and the rest is aluminum. The impurities contained in the alloy are less than 0.3%.

2. A process for producing an AlSi7Cu0.5Mg alloy, for producing the alloy as claimed in claim 1, characterized in that: The following steps are involved: Step 1: material smelting. First, aluminum, magnesium, zinc, iron, copper, manganese, silicon, titanium and strontium are put into a metal melting furnace (1) according to mass percentage for smelting. The temperature in the metal melting furnace (1) is adjusted to melt and preliminarily mix the above components to obtain a first metal solution. Step 2: uniform treatment, stirring the obtained first metal solution by ultrasonic or electromagnetic waves to make it uniformly mixed, so as to obtain a second metal solution; Step 3: Casting: inputting the second molten metal into a vacuum casting machine, and obtaining an alloy ingot through vacuum suction casting of the vacuum casting machine; Step 4: Workpiece production: the obtained alloy ingots are made into high-performance parts for automobile engines.

3. The AlSi7Cu0.5Mg alloy production process according to claim 2, characterized in that: In the step 1, aluminum is first added to a metal melting furnace (1), the temperature of the metal melting furnace (1) is increased to 770-910°C, the aluminum is melted into aluminum liquid, magnesium, zinc and strontium are then added to the aluminum liquid to obtain an aluminum-magnesium alloy solution, the temperature in the metal melting furnace (1) is increased to 1800-2000°C, powdered titanium, silicon, manganese, copper and iron are added to the aluminum liquid in sequence, and after melting, an aluminum-silicon-magnesium-copper alloy solution constituting a first metal solution is obtained.

4. The AlSi7Cu0.5Mg alloy production process according to claim 2, characterized in that: In the step 2, the temperature in the metal melting furnace (1) is adjusted to 760-780°C, and after standing for 10-30 minutes, the first metal solution is stirred by ultrasonic or electromagnetic waves to form a fully mixed second metal solution, and the frequency of the ultrasonic wave is 35kHz-80kHz.

5. The AlSi7Cu0.5Mg alloy production process according to claim 2, characterized in that: In the step three, the vacuum casting device (2) used is connected to the metal melting furnace (1), and the second metal liquid in the metal melting furnace (1) can be directly input into the vacuum casting device (2). The vacuum casting device (2) includes a machine base (3) and a machine body (4) installed on the machine base (3). The bottom of the machine base (3) has a bottom plate (31), and the bottom plate (31) has an extension section. The metal melting furnace (1) is arranged on the extension section. The metal melting furnace (1) has a feed port. A PLC controller is arranged in the machine base (3), and the PLC controller is used to control the vacuum casting device (2) and the metal melting furnace (1).

6. The AlSi7Cu0.5Mg alloy production process according to claim 5, characterized in that: The machine body (4) comprises an outer shell (6) and a vacuum chamber (5), wherein the vacuum chamber (5) is located inside the outer shell (6), and the outer shell (6) is provided with a plurality of pipes communicating with the vacuum chamber (5), and the outer shell (6) is provided with a sealing door (11), one end of the sealing door (11) is hinged to the outer shell (6), and the outer shell (6) is also provided with a locking member (13) for locking the sealing door (11), the locking member (13) is hinged to the outer shell (6), and a hand wheel (14) is provided on the locking member (13), and an observation window (12) is provided on the sealing door (11).

7. The AlSi7Cu0.5Mg alloy production process according to claim 6, characterized in that: The surfaces of the housing (6) and the sealing door (11) opposite to each other are respectively provided with sealing members (15). The sealing members (15) are a receiving member arranged on the housing (6) and a plug-in member arranged on the sealing door (11). The receiving member is annular and has a receiving groove. The receiving member is made of high-temperature resistant silicone rubber with a Shore hardness of 28-35. The plug-in member is "T"-shaped, with a protruding portion facing the receiving groove. The plug-in member is adhered to the sealing door (11). The plug-in member is made of high-temperature resistant silicone rubber with a Shore hardness of 28-35. When in use, it moves synchronously with the sealing door (11) and is then inserted into the receiving groove.

8. The AlSi7Cu0.5Mg alloy production process according to claim 6, characterized in that: The pipeline comprises a feed pipe (7), a discharge pipe (8), an air inlet pipe (9) and an air outlet pipe (10); the feed pipe (7) and the discharge pipe (8) are arranged on two sides of the outer shell (6) opposite to each other; the feed pipe (7) is connected to the metal melting furnace (1); the discharge pipe (8) is used to deliver the alloy ingot; the air inlet pipe (9) and the air outlet pipe (10) are both arranged on the top of the outer shell (6); the air inlet pipe (9) is used to inject inert gas into the vacuum chamber (5); the air outlet pipe (10) is used to evacuate the vacuum chamber (5); a pressure sensor is also provided on the shell on one side of the air inlet pipe (9); at least a portion of the pressure sensor extends into the vacuum chamber (5).

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