Baseball bat production method based on 6-series secondary aluminum

Abstract

The invention discloses a baseball bat production method based on 6-series secondary aluminum, the method comprises the steps of pretreatment, smelting, casting, homogenization treatment, extrusion, drawing, subsequent processing and the like, in the casting step, electromagnetic stirring treatment is adopted in a crystallizer, a Fe-containing phase with a large size is dispersed, in the homogenization treatment step, two stages are adopted, and in the subsequent processing step, two stages are adopted; the first-stage homogenization treatment is used for dissolving an Mg2Si phase with a low melting point into a matrix, the second-stage homogenization treatment is used for converting long-strip-shaped beta-AlFeSi into spherical alpha-Al (FeMn) Si and eliminating a harmful Fe phase, heating treatment is carried out on a drawing mold in the drawing step, and warm forming is beneficial to smoother drawing of the aluminum alloy and reduction of cracking phenomena; and other alloys do not need to be added in the smelting production process of the secondary aluminum, so that the production cost can be reduced while the performance is ensured, and the purposes of energy conservation, emission reduction and recycling are achieved.

Description

Technical Field

[0001] The invention relates to a method for producing sports equipment, in particular to a method for producing a baseball bat of 6 series recycled aluminum. Background Art

[0002] Currently, baseball bats are made by mixing pure aluminum ingots and intermediate alloys such as Mg-Al in a smelting furnace into a 6061 alloy composition and then heating and melting and casting. The 6061 alloy aluminum is made through extrusion, drawing, solid solution, and heat aging treatment. Its raw materials are mainly new aluminum ingots and intermediate alloy metals, and their prices are higher than those of recycled aluminum metals.

[0003] With the development of the times, in order to reduce costs and reduce carbon emissions in the production process, some manufacturers currently make new baseball bats from recycled aluminum alloy baseball bats. However, recycled aluminum alloy baseball bats contain more impurities. Remelting is mainly affected by relatively coarse Fe-containing phases such as AlFeSi, AlFeMn, and AlFeCr. During the extrusion and drawing process, it is easy to cause surface cracks and poor tensile properties. As a result, the remelted raw materials cannot be used directly. This requires the addition of other alloys in the production process to eliminate the influence of relatively coarse Fe-containing phases. For the composition and content of other alloys, it is necessary to make an accurate analysis of the remelted raw materials, which undoubtedly increases the difficulty of processing. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides a baseball bat production method based on 6 series recycled aluminum, which no longer needs to add other alloys during the regeneration process, reduces production costs, and achieves the purpose of energy conservation and emission reduction.

[0005] The technical solution adopted by the present invention to solve its technical problem is: A method for producing a baseball bat based on 6 series recycled aluminum, the method being as follows: (1) Pretreatment: Pretreatment of waste aluminum alloy baseball bats to obtain recycled aluminum raw materials; the pretreatment process includes sorting, crushing, washing, iron removal, paint removal and other well-known technologies in the field.

[0006] (2) Melting: The recycled aluminum raw materials are put into a smelting furnace for melting at a temperature of 700-750°C. After the recycled aluminum raw materials are completely melted, the surface scum is removed and the recycled aluminum liquid is obtained through deep bed filtration and degassing processes.

[0007] (3) Casting: The recycled aluminum liquid enters the electromagnetic casting crystallizer through the flow channel and is cast into a cast rod of the required diameter; the current turns of the electromagnetic casting crystallizer are 3000-8000 ampere-turns, the frequency is 0-100 Hz, and the diameter of the crystallizer is 150-200 mm.

[0008] (4) Homogenization treatment: The cast rods are subjected to two-stage homogenization treatment. The first-stage homogenization treatment is at a temperature of 520-550°C for 4-7 hours. The second-stage homogenization treatment is at a temperature of 550-570°C for 5-10 hours.

[0009] (5) Extrusion: Heat the cast rod to 430-460℃, heat the extrusion die to 420-450℃, and extrude the cast rod into a pipe of the required diameter at an extrusion speed of 0.3-1mm / s.

[0010] (6) Drawing: Cut the tube into appropriate lengths and place it in a drawing mold for drawing and stretching. During the drawing and stretching process, the drawing mold is heated. After multiple drawing processes, the finished product shape is initially achieved. In this step, the temperature of the drawing mold is 200-300°C and the drawing speed is 0.3-1mm / s.

[0011] (7) Subsequent processing: The subsequent processing is the same as the processing technology for manufacturing baseball bats made of new materials and is a conventional technology in this field.

[0012] The beneficial effects of the present invention are as follows: in the casting step, the crystallizer of the present application adopts electromagnetic stirring treatment to disperse the larger Fe-containing phase; in the homogenization step, there are two stages, the purpose of the first-stage homogenization treatment is to dissolve the Mg2Si phase with a low melting point into the matrix; the purpose of the second-stage homogenization treatment is to transform the long strip β-AlFeSi into the spherical α-Al(FeMn)Si and eliminate the harmful Fe phase; in the drawing step, the drawing mold is heated, and warm forming helps to make the aluminum alloy drawing smoother and reduce cracking. No other alloys need to be added in the recycled aluminum smelting production process, and while ensuring the performance, the production cost can be reduced, thereby achieving the purpose of energy saving, emission reduction and recycling and reuse. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0014] Figure 1 This is a photo of a cast rod without electromagnetic stirring.

[0015] Figure 2 This is a photo of the cast rod after drawing and stretching without electromagnetic stirring.

[0016] Figure 3 This is a photo of a cast rod with electromagnetic stirring.

[0017] Figure 4 This is a photo of the cast rod after drawing and stretching with electromagnetic stirring. DETAILED DESCRIPTION

[0018] The applicant analyzed two batches of aluminum alloy baseball bats after remelting. The raw material recovery time of the two batches of aluminum differed by two months. The composition is as follows:

[0019]

[0020] The above analysis results show that the Al content in the recycled aluminum alloy baseball bats reaches more than 98%, and the other components do not change much, so the difference in raw materials does not need to be considered in production.

[0021] A method for producing a baseball bat based on 6 series recycled aluminum, the method being as follows: (1) Pretreatment: Pretreatment: The waste aluminum alloy baseball bats are pretreated to obtain recycled aluminum raw materials; the pretreatment process includes sorting, crushing, washing, iron removal, paint removal and other well-known technologies in the field.

[0022] (2) Melting: The recycled aluminum raw material is put into a melting furnace for melting at a temperature of 700-750°C (generally, recycled baseball bats can be completely melted at 700°C, and there is no strict requirement for the temperature, and this range is acceptable). After the recycled aluminum raw material is completely melted, the surface scum is removed and the recycled aluminum liquid is obtained through deep bed filtration and degassing processes (aluminum liquid slag removal, aluminum liquid deep bed filtration, and aluminum liquid degassing are well-known technologies in the art).

[0023] (3) Casting: The recycled aluminum liquid enters the electromagnetic casting crystallizer through the flow channel and is cast into a cast rod of the required diameter. The current turns of the electromagnetic casting crystallizer are 3000-8000 ampere-turns, the frequency is 0-100Hz, and the diameter of the crystallizer is 150-200mm (there is no strict requirement, and this range is acceptable). Figure 1 This is a photo of a cast rod without electromagnetic stirring (taken with a metallographic microscope). Figure 3 This is a photo of a cast rod with electromagnetic stirring (taken under a metallographic microscope). It can be seen from the photo that the black Fe-containing second phase in the cast rod with electromagnetic stirring becomes fine and uniform under the action of electromagnetic stirring.

[0024] Electromagnetic casting crystallizer belongs to the common equipment in this field. It is selected to be equipped with a frequency converter, with a current turn of 1000-13000 ampere-turns and a frequency of 0-2100Hz. The purpose of electromagnetic stirring in this step is to disperse the larger Fe-containing phase into a uniform and fine one to avoid agglomeration. The electromagnetic parameters of the crystallizer are closely related to the distribution and size of the Fe-containing phase in the melt, and will also affect the forming of the terminal pipe product. When the Fe content of the ingot is high, setting the current turn to be larger will help the uniform dispersion and size reduction of the Fe-containing phase. However, if the current turn is too large, the melt will be unevenly crystallized or easily involved in the gas, resulting in casting defects. If the current turn is set too small, it will be unfavorable for the crushing and distribution of the Fe-containing phase. The frequency is generally related to the size of the crystallizer. The larger the diameter of the crystallizer, the smaller the frequency, the larger the stirring area, and the smaller the diameter of the crystallizer, the larger the frequency, and the smaller the stirring area. The selection of 3000-8000 ampere-turns and 0-100Hz in this step can be adjusted according to actual needs, and the adjustment method belongs to the conventional technology in this field.

[0025] (4) Homogenization treatment: The cast rods are subjected to two-stage homogenization treatment, the first-stage homogenization: the temperature is 520-550℃, the time is 4-7h, the second-stage homogenization: the temperature is 550-570℃, the time is 5-10h (the time and temperature of this step are not strictly required, and they can be within this range). The purpose of the first-stage homogenization treatment is to dissolve the Mg2Si phase with a low melting point into the matrix, and the purpose of the second-stage treatment is to transform the long strip-shaped β-AlFeSi into the spherical α-Al(FeMn)Si and eliminate the harmful Fe phase. This step adopts a long-term high-temperature two-stage homogenization treatment. During the homogenization treatment, the Mn element directly participates in the phase transformation process of the iron-rich phase. The iron-rich phase is transformed from the lath-shaped and brittle β-AlFeSi phase to the spherical (granular) α-Al(FeMn)Si phase, avoiding problems such as surface cracks and poor tensile properties in the subsequent drawing process.

[0026] (5) Extrusion: Heat the cast rod to 430-460°C, heat the extrusion die to 420-450°C, and extrude the cast rod into a pipe of the required diameter at an extrusion speed of 0.3-1 mm / s.

[0027] (6) Drawing: Cut the tube into appropriate lengths and place it in a drawing die for drawing and stretching. During the drawing and stretching process, the drawing die is heated. After multiple drawing processes, the finished product shape is initially achieved. In this step, the temperature of the drawing die is 200-300°C and the drawing speed is 0.3-1mm / s. In this step, the drawing die is heated to prevent the residual brittle Fe from affecting the surface during the homogenization process, which helps to make the aluminum alloy drawing smoother and reduce cracking. Figure 2 This is a photo of a cast rod after drawing and stretching without electromagnetic stirring (taken with an ordinary digital camera). Figure 4These are photos of cast rods with electromagnetic stirring after drawing and stretching (taken with an ordinary digital camera). It can be seen that obvious cracks appear on the surface of the cast rods without electromagnetic stirring after drawing and stretching, while the surface of the cast rods with electromagnetic stirring after drawing and stretching is smooth without obvious cracks.

[0028] (7) Subsequent processing: The subsequent processing is the same as the processing technology for manufacturing baseball bats made of new materials and is a conventional technology in this field.

[0029] Five batches of aluminum materials prepared by the method of the present application were subjected to room temperature tensile tests. The equipment and standards used in the tests were as follows: Experimental equipment: universal testing machine, model: CMT5504, implementation standard: GB / T 228-2002, and the test data are as follows:

[0030] The test data show that the aluminum material produced by the method of the present invention has good tensile strength, yield strength and elongation, and its performance is very close to that of the new 6061 alloy aluminum material. The method of the present invention does not need to add other alloys in the production process of recycled aluminum smelting, omits the steps of analyzing the re-smelted raw materials and adding other alloys, and can directly remelt the recycled waste aluminum alloy baseball bats. The performance of the baseball bats made of recycled aluminum can basically reach the performance of the baseball bats produced by using the new 6061 alloy aluminum, which can reduce production costs, reduce carbon emissions in the production process, and achieve the purpose of energy conservation and emission reduction.

[0031] The above implementation modes cannot limit the protection scope of the present invention. The equivalent modifications and changes made by those skilled in the art without departing from the overall concept of the present invention are still within the scope of the present invention.

Claims

1. A method for producing a baseball bat based on 6 series recycled aluminum, characterized in that The method is as follows: (1) Pretreatment: Pretreatment of waste aluminum alloy baseball bats to obtain recycled aluminum raw materials; (2) Melting: The recycled aluminum raw material is put into a smelting furnace for melting at a temperature of 700-750°C. After the recycled aluminum raw material is completely melted, the surface scum is removed and the recycled aluminum liquid is obtained through deep bed filtration and degassing processes; (3) Casting: The recycled aluminum liquid enters the electromagnetic casting crystallizer through the flow channel and is cast into cast rods of the required diameter; (4) Homogenization treatment: The cast rods are subjected to two-stage homogenization treatment, the first stage homogenization: the temperature is 520-550℃, the time is 4-7h; the second stage homogenization: the temperature is 550-570℃, the time is 5-10h; (5) Extrusion: Heat the cast rod to 430-460°C, heat the extrusion die to 420-450°C, and extrude the cast rod into a pipe of the required diameter at an extrusion speed of 0.3-1 mm / s; (6) Drawing: Cut the tube into appropriate lengths and place it in a drawing mold for drawing and stretching. During the drawing and stretching process, the drawing mold is heated. After multiple drawing processes, the finished product shape is initially achieved. (7) Subsequent processing.

2. The method for producing a baseball bat based on 6 series recycled aluminum according to claim 1, characterized in that The number of turns of the current of the electromagnetic casting crystallizer is 3000-8000 ampere-turns, the frequency is 0-100 Hz, and the diameter of the crystallizer is 150-200 mm.

3. The method for producing a baseball bat based on 6 series recycled aluminum according to claim 1, characterized in that In the drawing step, the temperature of the drawing mold is 200-300° C., and the drawing speed is 0.3-1 mm / s.

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