Continuous casting process for small-size aluminum alloy slab ingot

Abstract

A continuous casting process for a small-size aluminum alloy slab ingot comprises the following steps that firstly, an A00 aluminum ingot, an intermediate alloy and a recycled aluminum material are put into a melting furnace; secondly, when the temperature of molten aluminum in the melting furnace reaches 685 DEG C, an electromagnetic stirrer is started to conduct homogeneity treatment, and refining, degassing and deslagging treatment is conducted at the temperature of 720-750 DEG C; 3, the molten aluminum with qualified components is transferred into a heat preservation furnace and subjected to A < l > T < i5B < 0.6 > wire online grain refinement, argon rotor secondary degassing and foamed ceramic filter plate two-stage filtering, real-time monitoring is conducted, and it is ensured that the hydrogen content of the molten aluminum does not exceed 0.10 m < l > / 100 g Al; fourthly, the molten aluminum passes through a special slab ingot mold, is horizontally dragged by a dummy bar and is directly solidified into an aluminum alloy slab ingot with the corresponding size under the action of cooling water; 5, detecting internal defects of the aluminum alloy slab ingot; sixthly, T6 heat treatment is conducted; seventhly, machining is conducted to form a thermal management system valve body component; the method has the beneficial effects that a round bar vertical casting procedure is replaced, extrusion and cutting procedures are not needed, and the production cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of new materials, in particular to a continuous casting process of a small-size aluminum alloy flat ingot. Background Art

[0002] Compared with traditional fuel vehicles, new energy vehicles pay more attention to the regulation and management of the heat of the whole vehicle to ensure that all components operate within the optimal temperature range; the existing thermal management valve body materials such as aluminum thermal expansion valves or thermostatic valves have complex manufacturing processes, high material loss and high costs; the specific process is as follows: aluminum ingot melting → round bar casting → homogenization heat treatment → cutting → profile extrusion → cutting → T6 heat treatment → machining; at the same time, surface microcracks, bubbles, peeling and other defects are prone to occur during profile extrusion;

[0003] In view of the above situation, it is necessary to improve the existing valve body product casting process so that it can adapt to the current needs of valve body product processing and use. Summary of the invention

[0004] To achieve the above object, the technical solution of the present invention is a continuous casting process of a small-sized aluminum alloy slab, comprising the following steps:

[0005] Step 1: Put A00 aluminum ingot, master alloy and recycled aluminum into a melting furnace, where the proportion of recycled scrap aluminum is 40-60%;

[0006] Step 2: When the temperature of the aluminum liquid in the melting furnace reaches 685°C, turn on the electromagnetic stirrer for homogeneity treatment; when the temperature of the aluminum liquid reaches 720-750°C, carry out refining, degassing and deslagging treatment;

[0007] Step 3: The aluminum liquid with qualified ingredients is transferred to the holding furnace, and is subjected to online grain refinement by Al Ti5B0.6 wire, secondary degassing by argon rotor, and double-stage filtration by foam ceramic filter plate. Real-time monitoring is performed to ensure that the hydrogen content of the aluminum liquid does not exceed 0.10ml / 100g Al;

[0008] Step 4: The aluminum liquid passes through a special ingot mold, is horizontally pulled by the dummy rod, and directly solidifies into an aluminum alloy ingot of corresponding size under the action of cooling water;

[0009] Step 5: Detect internal defects of aluminum alloy slabs;

[0010] Step 6: Cut and perform T6 heat treatment;

[0011] Step 7: Machining the small flat ingot into a thermal management system valve body component.

[0012] As a further supplement to the technical solution, the sizes of the aluminum alloy slabs are: 25*65mm, 35*80mm, 50*90mm.

[0013] As a further supplement to the technical solution, the detection in step five is performed using ultrasonic flaw detection technology.

[0014] As a further supplement to the technical solution, in step six, the cast long flat ingot is cut into small flat ingots with a thickness of 20 to 30 mm, and the small flat ingots are subjected to T6 heat treatment to enhance their mechanical properties.

[0015] To further supplement the technical solution, in step six, the T6 heat treatment solution conditions are set to: 500-520°C, 4-5h; and the aging conditions are set to: 170-180°C, 6-8h.

[0016] The beneficial effect is that, in view of the characteristics of the valve body product, this case adopts the latest flat ingot horizontal continuous casting process, which can directly cast the valve body flat ingot material, replace the round bar vertical casting process, and does not require extrusion and cutting processes, thereby reducing production costs. DETAILED DESCRIPTION

[0017] In order to make the technical solution more clear to those skilled in the art, the technical solution of the present invention will be described in detail below:

[0018] A small-size aluminum alloy slab continuous casting process comprises the following steps:

[0019] Step 1: Put A00 aluminum ingot, master alloy and recycled aluminum into a melting furnace, where the proportion of recycled scrap aluminum is 40-60%;

[0020] Step 2: When the temperature of the aluminum liquid in the melting furnace reaches 685°C, turn on the electromagnetic stirrer for homogeneity treatment; when the temperature of the aluminum liquid reaches 720-750°C, carry out refining, degassing and deslagging treatment;

[0021] Step 3: The aluminum liquid with qualified ingredients is transferred to the holding furnace, and is subjected to online grain refinement by Al Ti5B0.6 wire, secondary degassing by argon rotor, and double-stage filtration by foam ceramic filter plate. Real-time monitoring is performed to ensure that the hydrogen content of the aluminum liquid does not exceed 0.10ml / 100g Al;

[0022] Step 4: The aluminum liquid passes through a special ingot mold, is horizontally pulled by the dummy rod, and directly solidifies into an aluminum alloy ingot of corresponding size under the action of cooling water;

[0023] Step 5: Detect internal defects of aluminum alloy slabs;

[0024] Step 6: Cut and perform T6 heat treatment;

[0025] Step 7: Machining the small flat ingot into a thermal management system valve body component.

[0026] As a further supplement to the technical solution, the sizes of the aluminum alloy slabs are: 25*65mm, 35*80mm, 50*90mm.

[0027] Among them, the detection in step five adopts ultrasonic flaw detection technology.

[0028] In step six, the cast long flat ingot is cut into small flat ingots with a thickness of 20 to 30 mm, and the small flat ingots are subjected to T6 heat treatment to strengthen their mechanical properties.

[0029] Among them, the T6 heat treatment solution conditions in step six are set to: 500-520°C, 4-5h; the aging conditions are set to: 170-180°C, 6-8h.

[0030] Among them, 1. The material composition of the valve body in this case is as follows:

[0031] Mg: 0.85-1.25%; Si: 0.35-0.80%; Fe: 0-0.85%; Mn: 0.10-0.25%; Cu: 0.05-0.15%; Cr: 0.05-0.20%; Ti: 0.08-0.15%;

[0032] In this case, the Fe content can reach 0.85%, and Mn, Cr and other elements are added to change the morphology of the Fe-rich phase and reduce its harm; reduce the downgrading of scrap aluminum and reduce the cost of raw materials.

[0033] Al Ti5B0.6 grain refiner is used to reduce the agglomeration of Ti B2 particles, reduce the genetic effect of B element in the process of recycling scrap aluminum for multiple uses, and increase the utilization ratio of scrap aluminum.

[0034] In this case, after degassing and purification, the aluminum liquid is used to prepare the aluminum alloy valve body material through a special flat ingot mold. The casting process adopts the latest flat ingot horizontal continuous casting process, with a casting temperature of 680-705℃, a casting speed of 200-350mm / min, and a cooling water temperature controlled at 25-32℃.

[0035] Typical aluminum alloy slab sizes are: 25*65mm, 35*80mm, 50*90mm. Currently, aluminum alloy slabs on the market are produced using a vertical casting process, with a thickness of 100-700mm and a width of 300-2900mm. There is no small-size aluminum alloy slab casting process, nor is there a horizontal continuous casting process for slabs.

[0036] After T6 heat treatment, product performance:

[0037] size Segregation layer thickness hardness tensile strength Yield Strength Elongation 25*65mm 1.5mm 98HB 323MPa 282MPa 11.5％ 35*80mm 1.8mm 95HB 321MPa 284MPa 13.2％ 50*90mm 2.0mm 96HB 316MPa 276MPa 14.1％

[0038] The above technical solutions only reflect the preferred technical solutions of the technical solutions of the present invention. Some changes that may be made to certain parts thereof by technicians in this technical field all reflect the principles of the present invention and fall within the protection scope of the present invention.

Claims

1. A continuous casting process for small-size aluminum alloy slabs, characterized in that: The following steps are involved: Step 1: Put A00 aluminum ingot, master alloy and recycled aluminum into a melting furnace, where the proportion of recycled scrap aluminum is 40-60%; Step 2: When the temperature of the aluminum liquid in the melting furnace reaches 685°C, turn on the electromagnetic stirrer for homogeneity treatment; when the temperature of the aluminum liquid reaches 720-750°C, carry out refining, degassing and deslagging treatment; Step 3: The aluminum liquid with qualified ingredients is transferred to the holding furnace, and is subjected to online grain refinement by AlTi5B0.6 wire, secondary degassing by argon rotor, and double-stage filtration by foam ceramic filter plate. Real-time monitoring is performed to ensure that the hydrogen content of the aluminum liquid does not exceed 0.10ml / 100g Al. Step 4: The aluminum liquid passes through a special ingot mold, is horizontally pulled by the dummy rod, and directly solidifies into an aluminum alloy ingot of corresponding size under the action of cooling water; Step 5: Detect internal defects of aluminum alloy slabs; Step 6: Cut and perform T6 heat treatment; Step 7: Machining the small flat ingot into a thermal management system valve body component.

2. A small-size aluminum alloy slab continuous casting process according to claim 1, characterized in that: The sizes of the aluminum alloy flat ingots are: 25*65mm, 35*80mm, 50*90mm.

3. A small-size aluminum alloy slab continuous casting process according to claim 1, characterized in that: The detection in step 5 adopts ultrasonic flaw detection technology.

4. A small-size aluminum alloy slab continuous casting process according to claim 1, characterized in that: In step six, the long flat ingot formed by casting is cut into small flat ingots with a thickness of 20 to 30 mm, and the small flat ingots are subjected to T6 heat treatment.

5. A small-size aluminum alloy slab continuous casting process according to claim 5, characterized in that: In step six, the T6 heat treatment solution conditions are set to: 500-520° C., 4-5 h; the aging conditions are set to: 170-180° C., 6-8 h.