Method for reducing aluminum alloy cast-rolled edge cracks

Abstract

The invention provides a method for reducing an aluminum alloy cast-rolled edge crack, and the aluminum alloy cast-rolled edge crack is prepared from the following raw materials in percentage by mass: 0.2-0.25% of Mn; 0.25 to 0.45 percent of Mg; 0.03 to 0.06 percent of Cr; 0.01 to 0.06 percent of Ti; the invention relates to the technical field of aluminum alloy cast rolling, in particular to the aluminum alloy cast rolling method, shearing force generated by deformation is effectively controlled, deformation is reduced, the height of a rolling area can be reduced by adopting a mode of reducing the length of the cast rolling area, and therefore the deformation is effectively reduced, and the yield of the cast rolling area is improved. According to the method, the condition of edge cracking of an aluminum alloy cast-rolling coil is avoided, the casting blank is preheated before the cast-rolling process, internal stress in the plate can be reduced through preheating, the plasticity and deformability of the plate can be improved, stress concentration in the rolling process is reduced, and therefore edge cracking is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum alloy casting and rolling, in particular to a method for reducing edge cracks of aluminum alloy casting and rolling. Background Art

[0002] Aluminum alloy is the most widely used type of nonferrous metal structural material in industry. It has been widely used in aviation, aerospace, automobile, machinery manufacturing, shipbuilding and chemical industries. With the rapid development of industrial economy, the demand for aluminum alloy welded structural parts is increasing, which has led to in-depth research on the weldability of aluminum alloy.

[0003] In the production process of aluminum foil billets, the casting and rolling method is often used, which makes the production process more efficient and can also play a role in energy conservation and emission reduction. It has become an important process method in the current aluminum alloy production. Compared with the hot rolling method, the casting and rolling method does not have the billet production process such as preheating, milling and hot rolling. The dendrites of the cast-rolled slab are smaller in spacing due to the existence of quenching, and the intermetallic compounds are small, which has great advantages in the production of foil billets. However, in the process of using the casting and rolling method to produce foil billets, there are also certain problems, which limit the normal use of the process method. The cracked edge of the cast-rolled coil is a key problem, which will affect the subsequent production of the cast-rolled strip. During the production process, it is very easy to be affected by the cracks of the cast and rolled coil. Under the action of tensile and compressive stresses, the crack range will increase on the edge. The crack problem is mainly caused by internal stress and thermal stress in the casting process and cutting stress caused by external factors such as mechanical cutting. In addition, excessive bending and extrusion during processing are also common causes of cracks. These stresses can cause cracks and cracks in aluminum cast and rolled slabs. The appearance of cracks in aluminum cast and rolled slabs will lead to concentrated force areas in the sheet material, reducing the strength and toughness of the entire sheet. Therefore, the crack problem of cast and rolled coils should be effectively controlled to ensure the quality and efficiency of aluminum alloy production. Summary of the invention

[0004] In order to overcome the existing problems, the embodiment of the present application provides a method for reducing cracks on the edges of aluminum alloy casting and rolling, effectively controls the shear force generated by deformation, reduces the amount of deformation, and by reducing the length of the casting and rolling zone, can achieve a reduction in the height of the rolling zone, thereby effectively reducing the amount of deformation and avoiding the occurrence of edge cracks in the aluminum alloy casting and rolling coil. In addition, the ingot is preheated before the casting and rolling process. Through preheating, the internal stress in the plate can be reduced, the plasticity and deformability of the plate can be improved, and the stress concentration during the rolling process can be reduced, thereby reducing the occurrence of edge cracks.

[0005] The technical solution adopted by the embodiment of the present application to solve the technical problem is:

[0006] A method for reducing cracks on the edge of aluminum alloy casting and rolling is prepared from the following raw materials in mass percentage: Mn: 0.2-0.25%; Mg: 0.25-0.45%; Cr: 0.03-0.06%; Ti: 0.01-0.06%; Fe: 0.4-0.6%, and the rest is Al and unavoidable impurity elements.

[0007] The method for reducing the cracks at the edge of aluminum alloy casting and rolling is applicable to the aluminum alloy plate for reducing the cracks at the edge of aluminum alloy casting and rolling as claimed in claim 1. The operating steps of the method for reducing the cracks at the edge of aluminum alloy casting and rolling are as follows:

[0008] Step 1: Melting

[0009] A circular heavy oil smelting furnace is used to add raw materials of each component by weight percentage into the smelting furnace for smelting. In the step 1, a furnace covering agent is used during the smelting process to reduce the generation of oxides and the adsorption of gases, so as to prevent the existence of oxides and the contamination of the molten metal by gases. In the step 1, the melt temperature of the smelting furnace is 700-750°C, and the furnace discharge temperature is 735-745°C.

[0010] Step 2: Refining

[0011] A resistance-heated static furnace is used, and the refining temperature in step 2 is 720-740°C;

[0012] Step 3: Purification

[0013] The refined metal liquid is purified by combining a refiner and glass cloth filtration;

[0014] Step 4: Molding

[0015] The purified molten metal is formed into a casting billet through a mold;

[0016] Step 5: Preheat

[0017] Preheating the formed ingot, wherein the preheating temperature in step 5 is 200-300° C. During preheating, the constant temperature of the heating furnace is 300° C. and the temperature is kept for more than 8 hours;

[0018] Step 6: Casting and rolling

[0019] The ingot is continuously cast and rolled using a double-row inclined casting and rolling mill. In step six, the length of the casting and rolling zone is 40 to 45 mm, and the casting and rolling speed is 0.95 to 1.10 m / min.

[0020] The advantages of the embodiments of the present application are:

[0021] The present invention effectively controls the shear force generated by deformation and reduces the deformation. By shortening the length of the casting and rolling zone, the height of the rolling zone can be reduced, thereby effectively reducing the deformation and avoiding the edge cracking of the aluminum alloy casting and rolling coil. The ingot is preheated before the casting and rolling process. Through preheating, the internal stress in the plate can be reduced, the plasticity and deformability of the plate can be improved, and the stress concentration in the rolling process can be reduced, thereby reducing the occurrence of edge cracks. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is a schematic flow chart of a method for reducing edge cracks in aluminum alloy casting and rolling. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. In addition, for the convenience of description below, the referenced "upper", "lower", "left", and "right" are the same as the upper, lower, left, and right directions of the drawings themselves. The "first", "second", etc. below are distinguished for the description and have no other special meanings.

[0024] The embodiment of the present application solves the problems in the prior art by providing a method for reducing edge cracks in aluminum alloy casting and rolling, effectively controls the shear force generated by deformation, reduces the amount of deformation, and can reduce the height of the rolling zone by shortening the length of the casting and rolling zone, thereby effectively reducing the amount of deformation and avoiding the occurrence of edge cracks in the aluminum alloy casting and rolling coil. In addition, the ingot is preheated before the casting and rolling process. Through preheating, the internal stress in the plate can be reduced, the plasticity and deformability of the plate can be improved, and the stress concentration during the rolling process can be reduced, thereby reducing the occurrence of edge cracks.

[0025] The technical solution in the embodiment of the present application is to solve the above problems, and the overall idea is as follows:

[0026] Example 1

[0027] This embodiment provides a method for reducing the edge cracks of aluminum alloy casting and rolling. Figure 1 As shown, it is prepared from the following raw materials in mass percentage: Mn: 0.2%; Mg: 0.25%; Cr: 0.03%; Ti: 0.01%; Fe: 0.4%, and the rest are Al and unavoidable impurity elements.

[0028] The operating steps of the method for reducing the edge crack of aluminum alloy casting are as follows:

[0029] Step 1: Melting

[0030] A circular heavy oil smelting furnace is used to add raw materials of each component by weight percentage into the smelting furnace for smelting. In step 1, a furnace covering agent is used during the smelting process to reduce the generation of oxides and the adsorption of gases, so as to prevent the existence of oxides and the contamination of the molten metal by gases. In step 1, the melt temperature of the smelting furnace is 700°C and the furnace discharge temperature is 735°C.

[0031] Step 2: Refining

[0032] A resistance-heated static furnace is used, and the refining temperature in step 2 is 720°C;

[0033] Step 3: Purification

[0034] The refined metal liquid is purified by combining a refiner and glass cloth filtration;

[0035] Step 4: Molding

[0036] The purified molten metal is formed into a casting billet through a mold;

[0037] Step 5: Preheat

[0038] Preheat the formed ingot. The preheating temperature in step 5 is 300°C. During preheating, the constant temperature of the heating furnace is 300°C and the temperature is kept for more than 8 hours.

[0039] Step 6: Casting and rolling

[0040] The ingot is continuously cast and rolled using a double-row inclined casting and rolling mill. In step six, the length of the casting and rolling zone is 40 mm, and the casting and rolling speed is 0.95 m / min.

[0041] After adopting the above-mentioned solution to the cracking of aluminum alloy cast-rolled coils, the casting zone length of the aluminum alloy cast-rolled billet is set to 40 mm, and the probability of cracking of no more than 10 mm in the aluminum alloy cast-rolled billet is reduced to 25%.

[0042] Example 2

[0043] This embodiment provides a method for reducing the edge cracks of aluminum alloy casting and rolling. Figure 1 As shown, it is prepared from the following raw materials in mass percentage: Mn: 0.2%; Mg: 0.25%; Cr: 0.03%; Ti: 0.01%; Fe: 0.4%, and the rest are Al and unavoidable impurity elements.

[0044] The operating steps of the method for reducing the edge crack of aluminum alloy casting are as follows:

[0045] Step 1: Melting

[0046] A circular heavy oil smelting furnace is used to add raw materials of each component by weight percentage into the smelting furnace for smelting. In step 1, a furnace covering agent is used during the smelting process to reduce the generation of oxides and the adsorption of gases, so as to prevent the existence of oxides and the contamination of the molten metal by gases. In step 1, the melt temperature of the smelting furnace is 700°C and the furnace discharge temperature is 735°C.

[0047] Step 2: Refining

[0048] A resistance-heated static furnace is used, and the refining temperature in step 2 is 720°C;

[0049] Step 3: Purification

[0050] The refined metal liquid is purified by combining a refiner and glass cloth filtration;

[0051] Step 4: Molding

[0052] The purified molten metal is formed into a casting billet through a mold;

[0053] Step 5: Preheat

[0054] Preheat the formed ingot. The preheating temperature in step 5 is 300°C. During preheating, the constant temperature of the heating furnace is 300°C and the temperature is kept for more than 8 hours.

[0055] Step 6: Casting and rolling

[0056] The ingot is continuously cast and rolled using a double-row inclined casting and rolling mill. In step six, the length of the casting and rolling zone is 42 mm, and the casting and rolling speed is 0.95 m / min.

[0057] After adopting the above-mentioned solution to the crack edge of the aluminum alloy cast-rolled coil, the casting zone length of the aluminum alloy cast-rolled billet is set to 42 mm, and the probability of crack edge not larger than 10 mm in the aluminum alloy cast-rolled billet is reduced to 20%.

[0058] Example 3

[0059] This embodiment provides a method for reducing the edge cracks of aluminum alloy casting and rolling. Figure 1 As shown, it is prepared from the following raw materials in mass percentage: Mn: 0.2%; Mg: 0.25%; Cr: 0.03%; Ti: 0.01%; Fe: 0.4%, and the rest are Al and unavoidable impurity elements.

[0060] The operating steps of the method for reducing the edge crack of aluminum alloy casting are as follows:

[0061] Step 1: Melting

[0062] A circular heavy oil smelting furnace is used to add raw materials of each component by weight percentage into the smelting furnace for smelting. In step 1, a furnace covering agent is used during the smelting process to reduce the generation of oxides and the adsorption of gases, so as to prevent the existence of oxides and the contamination of the molten metal by gases. In step 1, the melt temperature of the smelting furnace is 700°C and the furnace discharge temperature is 735°C.

[0063] Step 2: Refining

[0064] A resistance-heated static furnace is used, and the refining temperature in step 2 is 720°C;

[0065] Step 3: Purification

[0066] The refined metal liquid is purified by combining a refiner and glass cloth filtration;

[0067] Step 4: Molding

[0068] The purified molten metal is formed into a casting billet through a mold;

[0069] Step 5: Preheat

[0070] Preheat the formed ingot. The preheating temperature in step 5 is 300°C. During preheating, the constant temperature of the heating furnace is 300°C and the temperature is kept for more than 8 hours.

[0071] Step 6: Casting and rolling

[0072] The ingot is continuously cast and rolled using a double-row inclined casting and rolling mill. In step six, the length of the casting and rolling zone is 45 mm, and the casting and rolling speed is 0.95 m / min.

[0073] After adopting the above-mentioned solution to the crack edge of aluminum alloy cast-rolled coil, the casting zone length of the aluminum alloy cast-rolled billet is set to 45 mm, and the probability of crack edge not larger than 10 mm in the aluminum alloy cast-rolled billet is reduced to 10%.

[0074] Example 4

[0075] This embodiment provides a method for reducing the edge cracks of aluminum alloy casting and rolling. Figure 1 As shown, it is prepared from the following raw materials in mass percentage: Mn: 0.2%; Mg: 0.25%; Cr: 0.03%; Ti: 0.01%; Fe: 0.4%, and the rest are Al and unavoidable impurity elements.

[0076] The operating steps of the method for reducing the edge crack of aluminum alloy casting are as follows:

[0077] Step 1: Melting

[0078] A circular heavy oil smelting furnace is used to add raw materials of each component by weight percentage into the smelting furnace for smelting. In step 1, a furnace covering agent is used during the smelting process to reduce the generation of oxides and the adsorption of gases, so as to prevent the existence of oxides and the contamination of the molten metal by gases. In step 1, the melt temperature of the smelting furnace is 750°C and the furnace discharge temperature is 745°C.

[0079] Step 2: Refining

[0080] A resistance-heated static furnace is used, and the refining temperature in step 2 is 740°C;

[0081] Step 3: Purification

[0082] The refined metal liquid is purified by combining a refiner and glass cloth filtration;

[0083] Step 4: Molding

[0084] The purified molten metal is formed into a casting billet through a mold;

[0085] Step 5: Preheat

[0086] Preheat the formed ingot. The preheating temperature in step 5 is 300°C. During preheating, the constant temperature of the heating furnace is 300°C and the temperature is kept for more than 8 hours.

[0087] Step 6: Casting and rolling

[0088] The ingot is continuously cast and rolled using a double-row inclined casting and rolling mill. In step six, the length of the casting and rolling zone is 40 mm, and the casting and rolling speed is 0.95 m / min.

[0089] After adopting the above-mentioned solution to the cracking of the aluminum alloy cast-rolled coil, the casting zone length of the aluminum alloy cast-rolled billet is set to 45 mm, and the probability of cracking of no more than 10 mm in the aluminum alloy cast-rolled billet is reduced to 25%.

[0090] Example 5

[0091] This embodiment provides a method for reducing the edge cracks of aluminum alloy casting and rolling. Figure 1 As shown, it is prepared from the following raw materials in mass percentage: Mn: 0.2%; Mg: 0.25%; Cr: 0.03%; Ti: 0.01%; Fe: 0.4%, and the rest are Al and unavoidable impurity elements.

[0092] The operating steps of the method for reducing the edge crack of aluminum alloy casting are as follows:

[0093] Step 1: Melting

[0094] A circular heavy oil smelting furnace is used to add raw materials of each component by weight percentage into the smelting furnace for smelting. In step 1, a furnace covering agent is used during the smelting process to reduce the generation of oxides and the adsorption of gases, so as to prevent the existence of oxides and the contamination of the molten metal by gases. In step 1, the melt temperature of the smelting furnace is 750°C and the furnace discharge temperature is 745°C.

[0095] Step 2: Refining

[0096] A resistance-heated static furnace is used, and the refining temperature in step 2 is 740°C;

[0097] Step 3: Purification

[0098] The refined metal liquid is purified by combining a refiner and glass cloth filtration;

[0099] Step 4: Molding

[0100] The purified molten metal is formed into a casting billet through a mold;

[0101] Step 5: Preheat

[0102] Preheat the formed ingot. The preheating temperature in step 5 is 300°C. During preheating, the constant temperature of the heating furnace is 300°C and the temperature is kept for more than 8 hours.

[0103] Step 6: Casting and rolling

[0104] The ingot is continuously cast and rolled using a double-row inclined casting and rolling mill. In step six, the length of the casting and rolling zone is 42 mm, and the casting and rolling speed is 0.95 m / min.

[0105] After adopting the above-mentioned solution to the cracking of the aluminum alloy cast-rolled coil, the casting zone length of the aluminum alloy cast-rolled billet is set to 45 mm, and the probability of cracking of no more than 10 mm in the aluminum alloy cast-rolled billet is reduced to 20%.

[0106] Example 6

[0107] This embodiment provides a method for reducing the edge cracks of aluminum alloy casting and rolling. Figure 1 As shown, it is prepared from the following raw materials in mass percentage: Mn: 0.2%; Mg: 0.25%; Cr: 0.03%; Ti: 0.01%; Fe: 0.4%, and the rest are Al and unavoidable impurity elements.

[0108] The operating steps of the method for reducing the edge crack of aluminum alloy casting are as follows:

[0109] Step 1: Melting

[0110] A circular heavy oil smelting furnace is used to add raw materials of each component by weight percentage into the smelting furnace for smelting. In step 1, a furnace covering agent is used during the smelting process to reduce the generation of oxides and the adsorption of gases, so as to prevent the existence of oxides and the contamination of the molten metal by gases. In step 1, the melt temperature of the smelting furnace is 750°C and the furnace discharge temperature is 745°C.

[0111] Step 2: Refining

[0112] A resistance-heated static furnace is used, and the refining temperature in step 2 is 740°C;

[0113] Step 3: Purification

[0114] The refined metal liquid is purified by combining a refiner and glass cloth filtration;

[0115] Step 4: Molding

[0116] The purified molten metal is formed into a casting billet through a mold;

[0117] Step 5: Preheat

[0118] Preheat the formed ingot. The preheating temperature in step 5 is 300°C. During preheating, the constant temperature of the heating furnace is 300°C and the temperature is kept for more than 8 hours.

[0119] Step 6: Casting and rolling

[0120] The ingot is continuously cast and rolled using a double-row inclined casting and rolling mill. In step six, the length of the casting and rolling zone is 45 mm, and the casting and rolling speed is 0.95 m / min.

[0121] After adopting the above-mentioned solution to the crack edge of aluminum alloy cast-rolled coil, the casting zone length of the aluminum alloy cast-rolled billet is set to 45 mm, and the probability of crack edge not larger than 10 mm in the aluminum alloy cast-rolled billet is reduced to 10%.

[0122] Finally, it should be noted that: Obviously, the above embodiments are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from this are still within the scope of protection of the present invention.

Claims

1. An aluminum alloy plate with reduced edge cracks during aluminum alloy casting, characterized in that: The above-mentioned raw materials are prepared according to the mass percentage: Mn: 0.2-0.25%; Mg: 0.25-0.45%; Cr: 0.03-0.06%; Ti: 0.01~0.06%; Fe: 0.4~0.6%, and the rest are Al and inevitable impurity elements.

2. A method for reducing edge cracks in aluminum alloy casting, characterized in that: The method for reducing the cracks at the edge of aluminum alloy casting and rolling is applicable to the aluminum alloy plate for reducing the cracks at the edge of aluminum alloy casting and rolling as claimed in claim 1. The operating steps of the method for reducing the cracks at the edge of aluminum alloy casting and rolling are as follows: Step 1: Melting A circular heavy oil smelting furnace is used to add raw materials of each component by weight percentage into the smelting furnace for smelting; Step 2: Refining Use resistance heating static furnace; Step 3: Purification The refined metal liquid is purified by combining a refiner and glass cloth filtration; Step 4: Molding The purified molten metal is formed into a casting billet through a mold; Step 5: Preheat Preheating the formed ingot; Step 6: Casting and rolling A double-row inclined casting and rolling mill is used to continuously cast and roll the ingot.

3. A method for reducing edge cracks in aluminum alloy casting and rolling as claimed in claim 2, characterized in that: In the step 1, a furnace covering agent is used during the smelting process to reduce the generation of oxides and the adsorption of gases, so as to prevent the presence of oxides and the contamination of the molten metal by gases.

4. A method for reducing edge cracks in aluminum alloy casting and rolling as claimed in claim 2, characterized in that: In the step 1, the melt temperature of the smelting furnace is 700-750°C, and the outlet temperature is 735-745°C.

5. A method for reducing edge cracks in aluminum alloy casting and rolling as claimed in claim 2, characterized in that: The refining temperature in step 2 is 720-740°C.

6. A method for reducing edge cracks in aluminum alloy casting and rolling as claimed in claim 2, characterized in that: The preheating temperature in step 5 is 200-300° C. During preheating, the constant temperature of the heating furnace is 300° C. and the temperature is kept at more than 8 hours.

7. A method for reducing edge cracks in aluminum alloy casting and rolling as claimed in claim 2, characterized in that: In step six, the length of the casting zone is 40-45 mm, and the casting speed is 0.95-1.10 m / min.

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