A method for controlling the titanium element composition for aluminum alloy casting

Abstract

The present application relates to the technical field of aluminum alloy production, and discloses a titanium element component control method for aluminum alloy casting, which comprises the following steps: S1: feeding aluminum melt into a pre-furnace to add titanium additives: the titanium additives are placed in the pre-furnace, and aluminum liquid with a temperature higher than 840 DEG C is introduced into the pre-furnace, and then doping elements are added and mixed to obtain Zld101A casting aluminum alloy liquid; S2: refining the aluminum alloy liquid: inert gas and refining agent are introduced into the Zld101A casting aluminum alloy liquid, and degassing refining is carried out at a temperature of 720-760 DEG C; S3: standing the aluminum alloy liquid: after refining, the standing furnace is heated to 690-710 DEG C, and then the aluminum alloy liquid is transferred into the standing furnace to stand at a temperature of 690-720 DEG C; S4: casting and forming: the standing aluminum alloy liquid is transferred into a heat preservation chute to obtain a titanium-containing casting aluminum alloy product. The titanium element component control method for aluminum alloy casting mainly controls the component content and distribution of Ti elements in the aluminum alloy by accurately regulating the heating temperature at different casting stages.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aluminum alloy production, in particular to a titanium element composition control method for aluminum alloy casting. BACKGROUND

[0002] With the rapid development of modern industry and the continuous improvement of living standards, the reliability and comprehensive performance of castings in industrial production are increasingly demanding. Among them, cast aluminum alloy is used to replace part of the deformed aluminum alloy or to replace the forging, and can shorten the casting cycle and reduce the casting cost, because of its low price, isotropic organization, special organization, and easy production of complex shaped parts.

[0003] Among them, Zld101A cast aluminum alloy refers to a cast aluminum alloy with Al-Si-Mg-Ti as the main component and adding manganese, strontium, antimony and other alloying elements. In the production process of Zld101A cast aluminum alloy, the content and uniformity of Ti element greatly affect the application performance of aluminum alloy such as strength, hardness or toughness.

[0004] Therefore, for the production process of Zld101A cast aluminum alloy, there is an urgent need for a stable and accurate titanium element composition control method. SUMMARY

[0005] The technical problem to be solved by the present application is:

[0006] At present, in the production process of Zld101A cast aluminum alloy, there is a lack of composition control of Ti element, and the conventional casting process cannot stably and accurately ensure the doping effect of Ti element, resulting in unstable Ti content in the aluminum alloy product and uneven distribution, thereby affecting the application performance of the aluminum alloy such as strength, hardness or toughness.

[0007] The technical scheme adopted by the present application is:

[0008] The present application provides a titanium element composition control method for aluminum alloy casting, comprising the following steps:

[0009] S1: adding titanium to the aluminum melt in the pre-furnace: placing titanium additives in the pre-furnace, introducing aluminum liquid above 840℃ into the pre-furnace, and then adding doping elements, mixing to obtain Zld101A cast aluminum alloy liquid;

[0010] S2: aluminum alloy liquid refining: introducing inert gas and refining agent into the Zld101A cast aluminum alloy liquid, and carrying out degassing refining at a temperature of 720-760℃;

[0011] S3: Static treatment of the S3 aluminum alloy liquid: After refining, the static furnace is heated to 690-710℃, and then the aluminum alloy liquid is transferred into the static furnace for static treatment.

[0012] S4: Casting: The static aluminum alloy liquid is transferred into a casting channel, and when the titanium content in the aluminum alloy liquid is <0.13%, the casting temperature at the end of the channel is controlled to be 630-650℃, and when the titanium content in the aluminum alloy liquid is ≥0.13%, the casting temperature at the end of the channel is controlled to be 650-680℃, thereby obtaining a titanium-containing cast aluminum alloy product.

[0013] Preferably, in step S1, the titanium content in the titanium additive accounts for 0.08%-0.2% of the total mass of the Zld101A cast aluminum alloy liquid.

[0014] Preferably, in step S2, the degassing time is controlled to be 20-35min, and the refining time is controlled to be 20-35min.

[0015] Preferably, in step S2, after the inert gas is filled for degassing, the refining furnace is subjected to slag removal and impurity removal for further refining.

[0016] Preferably, the slag removal and impurity removal time is controlled to be 8-15min.

[0017] Preferably, in step S3, when the aluminum alloy liquid is transferred into the static furnace, the transfer time is controlled to be 30-35min, and the temperature loss during the transfer is controlled to be 10-30℃.

[0018] Preferably, in step S3, the static temperature is controlled to be 690-720℃, and the static time is controlled to be 20-60min.

[0019] Preferably, in step S4, the temperature of the casting channel is controlled to be 660-690℃, and the process temperature during casting is controlled to be 650-680℃.

[0020] The aluminum alloy obtained by using the above titanium element composition control method for casting has a titanium element content of 0.06-0.2% of the total weight of the aluminum alloy.

[0021] The beneficial effects of the present application are reflected in:

[0022] Titanium is a commonly used additive element in aluminum alloys. When titanium is added to high-strength and high-toughness cast copper-aluminum alloys, titanium and aluminum can form TiAl2 phase, which becomes a non-spontaneous core during crystallization, and can refine the structure and weld structure.

[0023] The application is based on a pre-furnace titanium adding process, and according to the titanium content range requirement of the target product, the middle line standard is taken as a reference point, and the floating range can be controlled to be less than or equal to 2%, so that the titanium element adding amount can be accurately controlled, and the error range is reduced to less than or equal to 5%; especially for the titanium content W(Ti) of 0.08-0.2%, by accurately controlling the temperature of the aluminum melt titanium, refining, standing and casting, the titanium content can be accurately and uniformly distributed, and the segregation is obviously reduced.

[0024] Overall, the titanium element composition control method for aluminum alloy casting of the application mainly controls the composition content and distribution of Ti element in the aluminum alloy by accurately regulating the heating temperature at different casting stages. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the embodiments of the application more clear, the technical scheme in the embodiments of the application will be clearly and completely described below. If the specific conditions are not specified in the embodiments, the conventional conditions or the conditions recommended by the manufacturer are used. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be purchased in the market.

[0026] The application provides a titanium element composition control method for aluminum alloy casting, which comprises the following steps:

[0027] (1) aluminum melt titanium adding: the titanium additive is placed in the aluminum melt pre-furnace, and then the high-temperature aluminum liquid above 840 DEG C is poured into the aluminum melt pre-furnace to realize rapid dissolution of titanium element; then, according to the raw material ratio of the aluminum alloy to be prepared, other titanium-containing aluminum alloy components such as industrial silicon and metal magnesium are added to obtain Zld101A casting aluminum alloy liquid.

[0028] Among them, the titanium element content in the titanium additive accounts for 0.08-0.2% of the total mass of the aluminum alloy liquid, when W(Ti) = 0.1%, the aluminum alloy obtained by casting has the best mechanical properties; when W(Ti) > 0.1%, the tensile strength and yield strength of the aluminum alloy obtained by casting are smaller, but the elongation is larger. In other titanium-containing aluminum alloy components, the industrial silicon accounts for 6.5-7.5% of the total mass of the aluminum alloy liquid, and the metal magnesium accounts for 0.3-0.4% of the total mass of the aluminum alloy liquid.

[0029] In this aluminum melt process, the temperature and violent impact rolling of the high-temperature aluminum liquid can make the titanium additive fully dissolved in the aluminum melt process, and can ensure the uniformity of Ti dissolution, and only one step operation can fully and efficiently complete the high-temperature dissolution and flow diffusion treatment; as the aluminum liquid continuously enters the furnace for dissolution, the titanium element also completely enters the melt in the furnace, that is, the titanium agent adding work is completed, and then the person skilled in the art can add other corresponding components according to the existing aluminum alloy raw material formula.

[0030] (2) The aluminum alloy liquid refining stage: the Zld101A cast aluminum alloy liquid is transferred into the smelting furnace, sufficient inert gas and refining agent are filled to remove the air in the furnace, and the degassing time is controlled to be about 20-35 min, then the smelting furnace is scraped slag and impurities by mechanical equipment, and the slagging time is controlled to be 8-15 min, so that each element component in the Zld101A cast aluminum alloy liquid is fully dissolved and mixed, the chemical composition is more uniform, and the Zld101A cast aluminum alloy melt has high purity; then the temperature in the refining furnace is controlled to be 700-730 DEG C (the best refining temperature is 720 DEG C), and the refining is performed for 20-35 min, and the process is continuously stirred to make the titanium uniformly distributed in the aluminum alloy liquid.

[0031] When the inert gas is filled for degassing, the smaller the degassing bubbles, the more uniform the distribution of titanium element molecules, and if the degassing bubbles are too large, it will lead to insufficient degassing, unstable titanium element composition and uneven distribution.

[0032] (3) The aluminum alloy liquid standing stage: after refining, the standing furnace is heated to 690-720 DEG C, and the heating time is controlled to be 20-40 min to prevent the process temperature of the Zld101A cast aluminum alloy liquid flowing into the standing furnace from being too low due to the low temperature of the standing furnace, so that the titanium element in the Zld101A cast aluminum alloy melt is precipitated and attached to the bottom of the standing furnace; then the Zld101A cast aluminum alloy liquid at 720-740 DEG C is transferred into the standing furnace, and the transfer furnace time is controlled to be 30-35 min, and the temperature loss is usually 10-30 DEG C during the period, and the standing treatment is performed at 690-720 DEG C for 20-60 min (the best standing temperature is 710 DEG C, and the corresponding standing time is 30 min).

[0033] Under the above temperature conditions, the titanium element is uniformly distributed and stable. In the actual operation process, the standing furnace temperature is adjusted according to the standing time, and when the temperature drops below 690 DEG C, the temperature is raised and / or maintained by continuous heating.

[0034] (4) Aluminum alloy casting stage: the aluminum alloy liquid is transferred from the smelting furnace to the 660-690℃ chute, and the temperature loss of the aluminum alloy liquid is controlled to be less than 30℃ during the transfer process to ensure that the components in the aluminum alloy liquid do not appear uneven distribution problems due to temperature reduction; when the titanium content in the aluminum alloy liquid is less than 0.13%, the casting temperature at the end of the chute is controlled to be 630-650℃ to avoid titanium elements from being attached to the vertical pipe and balance device, thereby effectively reducing energy consumption; when the titanium content in the aluminum alloy liquid is greater than or equal to 0.13%, the casting temperature at the end of the chute is controlled to be 650-680℃, and when the temperature is lower than the range, titanium elements are easily precipitated and attached to the casting vertical pipe and balance device, causing titanium element segregation and non-compliance of the finished product titanium element; then it is transferred to the casting point of 630-660℃, and the aluminum alloy product is cast; the temperature control of the casting process is 650-680℃, and through accurate control of each link, titanium element precipitation can be avoided.

[0035] <Embodiment>

[0036] Example 1

[0037] In this embodiment, the physicochemical standards of the titanium-containing aluminum alloy to be prepared are as follows:

[0038]

[0039] The components such as Al: 23000 kg, Ti: 50 kg, Si: 1790 kg, Mg: 85 kg and other alloy elements are mixed into the aluminum alloy liquid according to the amount.

[0040] According to the above proportioning amount, the titanium additive is placed in the pre-aluminum furnace, and then the high-temperature aluminum liquid at about 840℃ is charged into the pre-aluminum furnace in batches to make it fully tumble and mix uniformly; thereafter, the remaining components are added according to the amount, mixed uniformly, and the aluminum alloy liquid is obtained;

[0041] The aluminum alloy liquid is transferred into the refining furnace, N2 is charged until the air in the furnace is completely removed, and the degassing time is controlled to be about 25min; after degassing, the internal part of the static furnace is raked, and the raking time is controlled within 12min; then the temperature in the refining furnace is controlled at about 740℃, and the refining is carried out for 30min, during which the electromagnetic stirring is started to make the titanium uniformly distributed in the aluminum alloy liquid;

[0042] The above refined aluminum alloy liquid is sampled and analyzed, and the titanium content is 0.153%, which meets the process requirements, and the next step of converter static is carried out:

[0043] The static furnace is heated to 699°C, and the heating temperature rising time is controlled to be about 25 min; the refined aluminum alloy liquid is transferred into the static furnace at 730°C, and the transfer furnace time is controlled to be 32 min, and the static time is 40 min; during the static process, the temperature in the static furnace is controlled to be always kept at 690-720°C, and the titanium content in the static furnace is analyzed to be 0.151%, and the next process production can be carried out;

[0044] Finally, the aluminum alloy liquid is transferred from the smelting furnace to the about 695°C chute, and then the aluminum alloy liquid is transferred to the casting point under the condition that the temperature of the casting point is controlled to be about 655-665°C, and the aluminum alloy liquid is cast at the temperature of 650-680°C to obtain the Zld101A cast aluminum alloy product.

[0045] It is determined that the titanium content in the Zld101A cast aluminum alloy product is 0.147%, which meets the physical and chemical standard requirements of the titanium-containing aluminum alloy to be prepared in the embodiment.

[0046] Example 2

[0047] In the embodiment, the physical and chemical standard requirements of the titanium-containing aluminum alloy to be prepared are as follows:

[0048]

[0049] The components such as Al: 23000 kg, Ti: 54 kg, Si: 1830 kg, Mg: 87 kg and other alloy elements are mixed into the aluminum alloy liquid according to the amount.

[0050] According to the above proportioning amount, the titanium additive is placed in the pre-aluminum furnace, and then the high-temperature aluminum liquid at about 860°C is charged into the pre-aluminum furnace in batches to make it fully tumble and mix; thereafter, the remaining components are added according to the amount, and mixed to obtain the aluminum alloy liquid.

[0051] The aluminum alloy liquid is transferred into the refining furnace, N2 is charged until the air in the furnace is completely removed, and the degassing time is controlled to be about 25 min; after degassing, the inside of the static furnace is raked, and the raking time is controlled to be within 12 min; then the temperature in the refining furnace is controlled to be about 760°C, and the refining is carried out for 25 min, during which the electromagnetic stirring is started to make the titanium uniformly distributed in the aluminum alloy liquid.

[0052] The above refined aluminum alloy liquid is sampled and analyzed, and the titanium content is 0.156%, which meets the process requirements, and the next transfer and static operation is carried out:

[0053] The static furnace is heated to about 710°C, and the heating time is controlled to about 25 minutes. The refined aluminum alloy liquid is transferred into the static furnace when the temperature is about 740°C, and the transfer time is controlled to about 32 minutes. The temperature in the static furnace is controlled to be about 690-700°C during the static process.

[0054] Finally, the aluminum alloy liquid is transferred from the smelting furnace to a trough with a temperature of about 690°C. The temperature loss of the aluminum alloy liquid is controlled to be less than 30°C during the transfer process. The aluminum alloy liquid is transferred to the casting point under the condition that the temperature of the casting point is about 660°C, and the casting is performed at a temperature of about 650-680°C, thereby obtaining the Zld101A cast aluminum alloy product.

[0055] It is determined that the titanium content in the Zld101A cast aluminum alloy product is 0.145%, which meets the physical and chemical standard requirements of the titanium-containing aluminum alloy to be prepared in this embodiment.

[0056] Example 3

[0057] In this embodiment, the physical and chemical standard requirements of the titanium-containing aluminum alloy to be prepared are as follows:

[0058]

[0059] The components are mixed into the aluminum alloy liquid according to the following amounts: Al: 23000 kg, Ti: 34 kg, Si: 1790 kg, Mg: 85 kg, and other alloy elements.

[0060] The titanium additive is placed in the pre-aluminum furnace according to the above proportioning amount, and then the high-temperature aluminum liquid at about 860°C is charged into the pre-aluminum furnace in batches to make it fully tumble and mix. Then, the remaining components are added according to the amount, and mixed to obtain the aluminum alloy liquid.

[0061] The aluminum alloy liquid is transferred into the refining furnace, and N2 is charged until the air in the furnace is completely removed. The degassing time is controlled to be 20 minutes. After degassing, the interior of the static furnace is raked, and the raking time is controlled to be within 8 minutes. Then, the temperature in the refining furnace is controlled to be 760°C, and the refining is performed for 30 minutes. During this process, the electromagnetic stirring is turned on to make the titanium uniformly distributed in the aluminum alloy liquid.

[0062] The refined aluminum alloy liquid is sampled and analyzed, and the titanium content is 0.102%, which meets the process requirements. The next step of transfer and static process is performed.

[0063] The static furnace is heated to 710℃, and the heating temperature rising time is controlled to be about 20 min; the refined aluminum alloy liquid is transferred into the static furnace at 740℃, and the transfer furnace time is controlled to be 30 min, and the static time is 40 min; during the static process, the temperature in the static furnace is controlled to be always kept at 700-710℃, and the titanium content in the static furnace is analyzed to be 0.101%, and the next process production can be carried out;

[0064] Finally, the aluminum alloy liquid is transferred from the smelting furnace into the trough at about 685℃, and the temperature loss of the aluminum alloy liquid is controlled to be less than 30℃ during the transferring process into the trough; then the aluminum alloy liquid is transferred into the casting point under the condition that the temperature of the casting point is about 660℃, and the casting is carried out at the temperature range of 630-650℃, and the Zld101A cast aluminum alloy product is obtained.

[0065] It is determined that the titanium content in the Zld101A cast aluminum alloy product is 0.100%, which meets the physical and chemical standard requirements of the titanium-containing aluminum alloy to be prepared in the embodiment.

[0066] Comparative Example 1

[0067] The high-temperature aluminum liquid at about 840℃ is mixed with titanium additives, inorganic silicon, metal magnesium and other doping elements, and is placed in a refining furnace, and the temperature is controlled to be between 680-720℃, and the refining time is 40 min; then the aluminum alloy liquid after the refining is transferred into a static furnace, and is statically kept at 660-680℃ for 30 min; the aluminum alloy liquid after the static keeping is transferred into a trough, and is cast under the condition that the temperature is 630-650℃, and the titanium-containing aluminum alloy product is obtained.

[0068] <Experimental example>

[0069] Sample: Examples 1-3, Comparative Example 1

[0070] The Zld101A cast aluminum alloy products produced in Examples 1-3 and Comparative Example 1 are randomly sampled, and the related material properties such as tensile strength and hardness are determined, and the results are shown in Table 1 below:

[0071] Table 1: Material property determination results of samples

[0072] Tensile strength (MPa) Yield strength (MPa) Hardness (HBW) Elongation rate (%) Example 1 321.0 192.1 163 16.3 Example 2 316.7 187.4 159 15.2 Example 3 317.3 189.0 161 15.6 Comparative Example 1 304.5 172.2 143 12.5

[0073] As shown in Table 1, compared with the titanium-containing aluminum alloy product in Comparative Example 1, the Zld101A cast aluminum alloy products prepared by Examples 1-3 have obvious stronger performance advantages in strength and hardness, which indicates that by improving the temperature in the production process, the present application can solve the problems of low strength, low hardness and poor toughness of the existing titanium-containing aluminum alloy caused by uneven distribution of titanium elements.

[0074] The above merely provides the preferred embodiments of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the principles and technical scope of the present application shall fall into the scope of the present application.

Claims

1. A method for controlling the titanium element composition for casting an aluminum alloy, characterized by, Comprising the following steps: S1: adding titanium into the pre-furnace, and the content of titanium in the titanium additive accounts for 0.08%-0.2% of the total mass of the Zld101A cast aluminum alloy liquid, introducing the aluminum liquid with a temperature above 840 ℃ into the pre-furnace, and then adding the doping elements, mixing, and obtaining the Zld101A cast aluminum alloy liquid; S2: introducing inert gas and refining agent into the Zld101A cast aluminum alloy liquid, and performing degassing refining at a temperature of 720-760 ℃; S3: after refining, first heating the static furnace to 690-710 ℃, and then transferring the aluminum alloy liquid into the static furnace for static treatment; S4: pouring and forming the aluminum alloy liquid after static treatment into a trough, the temperature of the trough is 660-690 ℃, the process temperature during pouring is 650-680 ℃, when the content of titanium in the aluminum alloy liquid is <0.13%, the pouring temperature at the end of the trough is controlled to be 630-650 ℃, and when the content of titanium in the aluminum alloy liquid is ≥0.13%, the pouring temperature at the end of the trough is controlled to be 650-680 ℃, and a titanium-containing cast aluminum alloy product is obtained.

2. The method of controlling titanium element composition for aluminum alloy casting according to claim 1, characterized by, In step S2, the degassing time is controlled to be 20-35 min, and the refining time is controlled to be 20-35 min.

3. The method of controlling titanium element composition for aluminum alloy casting according to claim 1, characterized by, In step S2, after the inert gas is filled for degassing, the slag is removed for impurity removal, and then refined.

4. The method of controlling titanium element composition for aluminum alloy casting according to claim 3, characterized by, The time for slag removal and impurity removal is controlled to be 8-15 min.

5. The method of controlling titanium element composition for aluminum alloy casting according to Claim 1, characterized by In step S3, when the aluminum alloy liquid is transferred into the static furnace, the transfer furnace time is controlled to be 30-35 min, and the temperature loss during the transfer furnace is controlled to be 10-30 ℃.

6. The method of controlling titanium element composition for aluminum alloy casting according to claim 1, characterized by In step S3, the static temperature is 690-720 ℃, and the static time is 20-60 min.

7. An aluminum alloy obtained by the method according to any one of claims 1-6.

8. The aluminum alloy of claim 7, wherein, The content of titanium accounts for 0.06-0.2% of the total weight of the aluminum alloy.

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