A method for cooling and quenching the inner and outer cavities of a multi-cavity aluminum alloy extruded profile

Abstract

The present invention belongs to the technical field of aluminum alloy profile extrusion, and specifically relates to a method for cooling and quenching the inner and outer cavities of a multi-cavity aluminum alloy extruded profile. The method comprises the following steps: Step 1: Determine and analyze the composition of aluminum and aluminum alloy profiles; Step 2: Place the mold in a heating furnace for heating; Install the upper mold cooling nozzle and the lower mold cooling nozzle; Install the mold after the upper mold cooling nozzle and the lower mold cooling nozzle are installed on the extruder; Step 3: Input various extrusion parameters of the extruded product into the extruder through the control panel; Step 4: At the beginning of the extrusion production, start the cold press to cool the inner cavity and outer wall of the aluminum profile at the same time; Step 5: Perform a tensile test on the aluminum and aluminum alloy profile using an electronic universal testing machine to obtain the extension strength, tensile strength and elongation after fracture values. The quenching method of the present invention can achieve simultaneous cooling and quenching of the outer wall and inner cavity of the aluminum profile, thereby improving the overall performance of the aluminum profile.

Description

Technical Field

[0001] The invention belongs to the technical field of aluminum alloy profile extrusion, and in particular relates to a method for cooling and quenching inner and outer cavities of a multi-cavity aluminum alloy extruded profile. Background Art

[0002] Aluminum profile online quenching cooling is divided into different types according to different cooling rates: Figure 1 The water ring cooling quenching, water mist cooling quenching and Figure 2 The air-cooled quenching shown and the water-ring quenching cooling are to pass the extrusion machine produced profile through the center of the water ring. Multiple nozzles are distributed around the annular water ring, and then a large amount of cooling water is sprayed from the nozzles of the annular water ring to cool and quench the extruded profile; while the water mist cooling quenching and air-cooled quenching are to cool the profile by blowing a large amount of air and water mist from the air outlet above the extrusion outlet channel. The current quenching cooling methods all cool and quench the outer surface of the profile. The subway side beam profile has many cavities and large wall thickness differences. It is often the case that the quenching of the thicker wall is not thorough and the mechanical properties are unqualified. Quenching is a key condition for improving the mechanical properties of aluminum profiles. The higher the quenching rate, the better the quenching effect, and the higher the mechanical properties after quenching. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for cooling and quenching the inner and outer cavities of a multi-cavity aluminum alloy extruded profile, so as to solve the problem that the online quenching method cannot effectively perform online quenching and cooling of the inner cavity of the multi-cavity aluminum profile, resulting in the inner cavity performance of the multi-cavity aluminum profile being lower than the outer wall performance. The quenching method of the present invention can realize simultaneous cooling and quenching of the outer wall and inner cavity of the aluminum profile, thereby improving the overall performance of the aluminum profile.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A method for cooling and quenching the inner and outer cavities of a multi-cavity aluminum alloy extruded profile comprises the following steps:

[0006] Step 1: Determine and analyze the composition of aluminum and aluminum alloy profiles;

[0007] Step 2: Place the mold consisting of the upper mold and the lower mold into a heating furnace for heating; install the upper mold cooling nozzle to the mold core of the heated upper mold, and install the lower mold cooling nozzle to the working belt outlet end of the heated lower mold; install the mold with the upper mold cooling nozzle and the lower mold cooling nozzle installed on the extruder;

[0008] Step 3: Input various extrusion parameters of the extruded product into the extruder through the control panel;

[0009] Step 4: At the beginning of extrusion production, the cold press is started; aluminum profile extrusion begins. During the extrusion process, the liquid nitrogen in the cold press is diverted through the cooling pipe into the cooling channel and the lower die cooling pipe, and then enters the upper die cooling nozzle through the cooling channel, and enters the lower die cooling nozzle through the lower die cooling pipe, cooling the inner cavity and outer wall of the aluminum profile at the same time;

[0010] Step 5: Perform a tensile test on aluminum and aluminum alloy profiles using an electronic universal testing machine to obtain the values ​​of elongation, tensile strength, and elongation after fracture.

[0011] The mold heating temperature in step 2 is 490-510°C.

[0012] The extrusion parameters described in step 3 are specifically an extrusion speed of 1.0 to 1.5 m / min; different liquid nitrogen supply rates are selected in production according to process requirements to achieve online quenching on the quenching device. The liquid nitrogen pressure range is usually 0.5 to 3 MPa, the temperature entering the quenching zone is 400 to 560°C, and the temperature after leaving the quenching zone is ≤100°C.

[0013] The technical effects of the present invention are:

[0014] The quenching method of the present invention solves the problem that the inner cavity of the subway side beam extruded aluminum profile cannot be cooled and quenched, and the problem that the wall thickness of the multi-cavity profile with large thickness difference is unqualified. p 0.2=280~290MPa,R m =320~340MPa, elongation after fracture =12~14% meet the standard requirements. It improves the overall mechanical properties of the inner cavity and outer wall of the subway side beam aluminum profile. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of water ring cooling quenching;

[0016] Figure 2 It is a schematic diagram of air cooling quenching;

[0017] Figure 3 Schematic diagram of the multi-cavity extruded aluminum profile inner cavity cooling and quenching device of the present invention installed in an extruder;

[0018] Figure 4 Schematic diagram of the structure of the multi-cavity extruded aluminum profile inner cavity cooling and quenching device of the present invention;

[0019] Figure 5 A side view of the structure of the multi-cavity extruded aluminum profile inner cavity cooling and quenching device of the present invention;

[0020] Figure 6 A top view of the structure of the multi-cavity extruded aluminum profile inner cavity cooling and quenching device of the present invention;

[0021] Figure 7Schematic diagram of the upper mold cooling nozzle of the present invention;

[0022] Figure 8 Partial view of the upper mold cooling nozzle of the present invention;

[0023] Figure 9 The present invention Figure 8 AA schematic diagram;

[0024] Figure 10 The present invention Figure 8 BB schematic diagram;

[0025] Figure 11 Schematic diagram of the cooling channel of the present invention;

[0026] 1-Extruder, 2-Cold press, 3-Cooling pipe, 4-Upper die, 5-Extruded product, 6-Upper die working belt, 7-Upper die cooling nozzle, 8-Cooling channel, 9-Air outlet, 10-Bolt hole, 11-Thermal insulation layer. DETAILED DESCRIPTION

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0028] Example 1

[0029] A method for cooling and quenching the inner and outer cavities of a multi-cavity aluminum alloy extruded profile comprises the following steps:

[0030] Subway side beam aluminum profile extrusion product 5 inner cavity cooling quenching

[0031] Step 1: Ingredient detection:

[0032] The composition of aluminum and aluminum alloys in accordance with GB / T7999-2015 was analyzed using an ARL-3460 direct reading spectrometer. The specific composition is shown in Table 1.

[0033] Table 1 Aluminum and aluminum alloy composition

[0034] element Si Fe Cu Mn Mg Cr Zn Ti impurities Al content 0.7 0.17 0.2 0.26 0.6 0.18 0.03 0.03 0.05 margin

[0035] Step 2: Place the mold consisting of the upper mold 4 and the lower mold into a heating furnace for heating at a temperature of 490-510°C; install the upper mold cooling nozzle 7 on the mold core of the heated upper mold 4, and install the lower mold cooling nozzle on the outlet end of the lower mold working belt of the heated mold; install the mold with the upper mold cooling nozzle 7 and the lower mold cooling nozzle installed on the extruder 1;

[0036] Step 3: Input various extrusion parameters of the extruded product into the extruder 1 through the control panel. The extrusion speed is 1.0 m / min and the weight per meter is 28.356 kg / m. Different liquid nitrogen supply amounts are selected in production according to the process requirements to achieve the purpose of online quenching in the quenching device. Usually, the liquid nitrogen pressure is 0.8 MPa, the temperature entering the quenching zone is 530°C, and the temperature after leaving the quenching zone is ≤40°C.

[0037] Step 4: At the beginning of extrusion production, the cold press 2 is started; aluminum profile extrusion begins. During the extrusion process, the liquid nitrogen in the cold press 2 is diverted through the cooling pipe 3 into the cooling channel 8 and the lower die cooling pipe, and then enters the upper die cooling nozzle 7 through the cooling channel 8, and enters the lower die cooling nozzle through the lower die cooling pipe, cooling the inner cavity and outer wall of the aluminum profile at the same time; the final discharge temperature is 35-40°C;

[0038] Step 5: Mechanical properties analysis:

[0039] Tensile tests were conducted using an AG-X 100kN electronic universal testing machine according to the test standard GB / T6892-2015, Aluminum and aluminum alloy extruded profiles for general industrial use. The test method is GB / T16865-2013, Specimens and methods for tensile testing of wrought aluminum, magnesium, and their alloy products. Tensile tests were conducted on three aluminum profile specimens extruded in step 4. The elongation, tensile strength, and elongation at break were obtained, as shown in Table 2.

[0040] Table 2 Mechanical properties results

[0041]

[0042] Example 2

[0043] A method for cooling and quenching the inner and outer cavities of a multi-cavity aluminum alloy extruded profile comprises the following steps:

[0044] Cooling and quenching of inner cavity of extruded aluminum profiles for subway side beams

[0045] Step 1: Ingredient detection:

[0046] The composition of aluminum and aluminum alloys in accordance with GB / T7999-2015 was analyzed using an ARL-3460 direct reading spectrometer. The specific composition is shown in Table 3.

[0047] Table 3 Aluminum and aluminum alloy composition

[0048] element Si Fe Cu Mn Mg Cr Zn Ti impurities Al content 0.7 0.16 0.15 0.26 0.6 0.17 0.04 0.04 0.05 margin

[0049] Step 2: Place the mold consisting of the upper mold 4 and the lower mold into a heating furnace for heating at a temperature of 490-510°C; install the upper mold cooling nozzle 7 on the core of the heated upper mold 4, and install the lower mold cooling nozzle on the outlet end of the heated lower mold working belt; install the mold with the upper mold cooling nozzle 7 and the lower mold cooling nozzle installed on the extruder 1;

[0050] Step 3: Input various extrusion parameters of the extruded product into the extruder 1 through the control panel. The extrusion speed is 1.2m / min and the weight per meter is 28.356kg / m. Different liquid nitrogen supply amounts are selected in production according to the process requirements to achieve the purpose of online quenching in the quenching device. Usually, the liquid nitrogen pressure is 1.0MPa, the temperature entering the quenching zone is 520℃, and the temperature after leaving the quenching zone is ≤30℃.

[0051] Step 4: At the beginning of extrusion production, the cold press 2 is started; aluminum profile extrusion begins. During the extrusion process, the liquid nitrogen in the cold press 2 is diverted through the cooling pipe 3 into the cooling channel 8 and the lower die cooling pipe, and then enters the upper die cooling nozzle 7 through the cooling channel 8, and enters the lower die cooling nozzle through the lower die cooling pipe, cooling the inner cavity and outer wall of the aluminum profile at the same time; the final discharge temperature is 35-40°C;

[0052] Step 5: Mechanical properties analysis:

[0053] Tensile tests were conducted using an AG-X 100kN electronic universal testing machine. The test standard is GB / T6892-2015, Aluminum and aluminum alloy extruded profiles for general industrial use. The test method is GB / T16865-2013, Specimens and methods for tensile testing of wrought aluminum, magnesium, and their alloy products. Tensile tests were conducted on three aluminum profile specimens extruded in step 2. The elongation, tensile strength, and elongation at break were obtained, as shown in Table 4.

[0054] Table 4 Mechanical properties results

[0055]

[0056] Example 3

[0057] A method for cooling and quenching the inner and outer cavities of a multi-cavity aluminum alloy extruded profile comprises the following steps:

[0058] Cooling and quenching of inner cavity of extruded aluminum profiles for subway side beams

[0059] Step 1: Ingredient detection:

[0060] The composition of aluminum and aluminum alloys in accordance with GB / T7999-2015 was analyzed using an ARL-3460 direct reading spectrometer. The specific composition is shown in Table 5.

[0061] Table 5 Composition of aluminum and aluminum alloys

[0062] element Si Fe Cu Mn Mg Cr Zn Ti impurities Al content 0.7 0.17 0.16 0.26 0.6 0.17 0.04 0.04 0.05 margin

[0063] Step 2: Place the mold consisting of the upper mold 4 and the lower mold into a heating furnace for heating at a temperature of 490-510°C; install the upper mold cooling nozzle 7 on the core of the heated upper mold 4, and install the lower mold cooling nozzle on the outlet end of the heated lower mold working belt; install the mold with the upper mold cooling nozzle 7 and the lower mold cooling nozzle installed on the extruder 1;

[0064] Step 3: Input various extrusion parameters of the extruded product into the extruder 1 through the control panel. The extrusion speed is 1.1m / min and the weight per meter is 28.356kg / m. Different liquid nitrogen supply amounts are selected in production according to the process requirements to achieve the purpose of online quenching in the quenching device. Usually, the liquid nitrogen pressure is 1.2MPa, the temperature entering the quenching zone is 515℃, and the temperature after leaving the quenching zone is ≤35℃.

[0065] Step 4: At the beginning of extrusion production, the cold press 2 is started; aluminum profile extrusion begins. During the extrusion process, the liquid nitrogen in the cold press 2 is diverted through the cooling pipe into the cooling channel 8 and the lower die cooling pipe, and then enters the upper die cooling nozzle 7 through the cooling channel 8, and enters the lower die cooling nozzle through the lower die cooling pipe, cooling the inner cavity and outer wall of the aluminum profile at the same time; the final discharge temperature is 35-40°C;

[0066] Step 5: Mechanical properties analysis:

[0067] Tensile tests were conducted using an AG-X 100kN electronic universal testing machine. The test standard is GB / T6892-2015, Aluminum and aluminum alloy extruded profiles for general industrial use. The test method is GB / T16865-2013, Specimens and methods for tensile testing of wrought aluminum, magnesium, and their alloy products. Tensile tests were conducted on three aluminum profile specimens extruded in step 2. The elongation, tensile strength, and elongation at break were obtained, as shown in Table 6.

[0068] Table 6 Mechanical properties results

[0069]

[0070] Whether it is embodiment 1, embodiment 2 or embodiment 3, they are all realized based on an extruder equipped with the multi-cavity extruded aluminum profile inner cavity cooling and quenching device.

[0071] like Figures 3 to 11As shown, the multi-cavity extruded aluminum profile inner cavity cooling and quenching device includes a mold upper mold 4 and a mold lower mold. The extrusion end of the mold upper mold 4 is provided with a mold core. The mold lower mold is arranged with a mold lower mold working belt according to the end face shape of the extruded product. The end of the mold core and the end of the mold lower mold working belt are respectively installed with an upper mold cooling nozzle 7 and a lower mold cooling nozzle. The mold upper mold 4 is provided with a cooling channel 8 connected to the upper mold cooling nozzle 7. Specifically, a vertical cooling channel is processed from the top of the mold upper mold 4 to the mold core, and several horizontal cooling channels are formed from the mold core to the corresponding upper mold cooling nozzle 7, and several horizontal cooling channels are connected to the vertical cooling channel to form a cooling channel 8. The inlet end of the cooling channel 8 and the inlet end of the lower mold cooling nozzle are connected to the outlet end of the cold press through the cooling pipe 3 and the lower mold cooling pipe respectively.

[0072] Bolt holes 10 and air outlet holes 9 are processed at both ends of the upper mold cooling nozzle 7, and the air outlet holes 9 are located at the closed end of the upper mold cooling nozzle 7.

[0073] The lower mold cooling nozzle is an annular body, and air outlet holes 9 are processed along the surface of the annular body opposite to the outer wall of the aluminum profile.

[0074] The outer shape of the upper mold cooling nozzle 7 is consistent with the inner shape of the aluminum profile.

[0075] The inner hole of the cooling channel 8 is provided with a heat insulating layer 11 to form a cooling channel. The heat insulating layer 11 is made of glass fiber and a high heat-resistant composite material.

Claims

1. A method for cooling and quenching the inner and outer cavities of a multi-cavity aluminum alloy extruded profile, characterized in that: The following steps are involved: Step 1: Determine and analyze the composition of aluminum and aluminum alloy profiles; Step 2: Place the mold consisting of the upper mold and the lower mold into a heating furnace for heating; install the upper mold cooling nozzle to the mold core of the heated upper mold, and install the lower mold cooling nozzle to the working belt outlet end of the heated lower mold; install the mold with the upper mold cooling nozzle and the lower mold cooling nozzle installed on the extruder; Step 3: Input the extrusion parameters of the extruded product into the extruder through the control panel; the specific extrusion parameters are an extrusion speed of 1.0-1.5 m / min; select different liquid nitrogen supply amounts according to process requirements in production to achieve online quenching on the quenching device. The liquid nitrogen pressure range is 0.5-3 MPa, the temperature entering the quenching zone is 400-560°C, and the temperature after leaving the quenching zone is ≤100°C; At the beginning of extrusion production, the cold press is started; aluminum profile extrusion begins. During the extrusion process, the liquid nitrogen in the cold press is diverted through the cooling pipe into the cooling channel and the lower die cooling pipe, and then enters the upper die cooling nozzle through the cooling channel, and enters the lower die cooling nozzle through the lower die cooling pipe, cooling the inner cavity and outer wall of the aluminum profile at the same time; The multi-cavity aluminum alloy extruded profile includes a subway side beam extruded aluminum profile.

2. The method for cooling and quenching the inner and outer cavities of a multi-cavity aluminum alloy extruded profile according to claim 1, characterized in that: It also includes the following steps: After quenching and cooling, a tensile test needs to be performed, specifically: a tensile test is performed on aluminum and aluminum alloy profiles using an electronic universal testing machine to obtain the extension strength, tensile strength and elongation after fracture values.

3. The method for cooling and quenching the inner and outer cavities of a multi-cavity aluminum alloy extruded profile according to claim 1, characterized in that: The mold heating temperature in step 2 is 490-510°C.

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