阅读说明：本技术 一种高性能细晶粒零粗晶环铝合金及其制备工艺及应用 (High-performance fine-grain zero-coarse-grain ring aluminum alloy and preparation process and application thereof ) 是由 王彪 张洪文 王庆庆 于 2021-08-10 设计创作，主要内容包括：本发明提供一种高性能细晶粒零粗晶环铝合金制备工艺,所述工艺具体包括以下步骤：步骤S1,铝锭熔铸；步骤S2,均匀化处理；步骤S3,预热；步骤S4,挤压；步骤S5,淬火；步骤S6,拉直；步骤S7,人工固溶及时效热处理。本发明实施例在铝合金铸棒的挤压步骤前进行预热,以及对挤压模具进行参数改进设计,避免挤压过程中摩擦热导致外层晶核快速长大形成粗晶环；通过本发明实施例制备工艺制备得到的铝合金产品强度高、细晶粒且无粗晶环,其抗拉强度为400～430MPa,屈服强度为380～400MPa,延伸率为10～13%,晶粒级别指数达6～8级且产品无粗晶环,为客户后续加工提供了优良的素材。(The invention provides a preparation process of a high-performance fine-grain zero-coarse-grain ring aluminum alloy, which specifically comprises the following steps: step S1, casting aluminum ingots; step S2, homogenization treatment; step S3, preheating; step S4, extruding; step S5, quenching; step S6, straightening; and step S7, artificial solid solution and aging heat treatment. According to the embodiment of the invention, preheating is carried out before the extrusion step of the aluminum alloy cast rod, and parameter improvement design is carried out on the extrusion die, so that the phenomenon that outer-layer crystal nuclei grow rapidly to form coarse crystal rings due to friction heat in the extrusion process is avoided; the aluminum alloy product prepared by the preparation process provided by the embodiment of the invention has high strength, fine grains and no coarse grain ring, the tensile strength is 400-430 MPa, the yield strength is 380-400 MPa, the elongation is 10-13%, the grain grade index reaches 6-8 grade, and the product has no coarse grain ring, so that an excellent material is provided for subsequent processing of customers.)

1. A preparation process of a high-performance fine-grain zero-coarse-grain ring aluminum alloy is characterized by comprising the following steps of:

step S1, casting aluminum ingots: selecting an aluminum alloy raw material to carry out smelting casting, and casting in a vacuum direct cooling casting system at the speed of 36-40 mm/min during casting to obtain an aluminum alloy casting rod;

the aluminum alloy raw material comprises the following components in percentage by mass: silicon: 1.0-1.1%, iron: 0.1-0.2%, copper: 0.45-0.55%, manganese: 0.6-0.7%, magnesium: 0.8 to 0.85%, chromium: 0.1 to 0.2% and titanium: 0.15 to 0.2 percent of aluminum and inevitable impurities as the rest;

step S2, homogenization: homogenizing the aluminum alloy cast rod obtained in the step S1 at 490-510 ℃ for 9-11 h, and cooling the aluminum alloy cast rod to room temperature after homogenizing;

step S3, preheating: respectively preheating the aluminum alloy cast rod, the extrusion die and the die cylinder which are homogenized in the step S2;

step S4, extrusion: extruding the aluminum alloy cast rod preheated in the step S3 by using an extruder;

step S5, quenching: carrying out on-line water penetration quenching on the product extruded in the step S4, wherein the quenching medium is circulating water;

step S6, straightening: straightening and sawing the product quenched and cooled in the step S5, wherein the straightening rate is 0.3-1.0%;

step S7, artificial solid solution and time-effect heat treatment: and (5) carrying out artificial solution heat treatment and aging heat treatment on the product sawn in the step S6.

2. The process of claim 1, wherein the aluminum alloy is selected from the group consisting of aluminum, copper, chromium,

in the step S3, the preheating temperature of the aluminum alloy cast rod is 480-500 ℃, and the head-tail temperature gradient of the cast rod is 10-20 ℃; the preheating temperature of the extrusion die is 470-490 ℃; the preheating temperature of the die cylinder is 425-435 ℃.

3. The process of claim 1, wherein the aluminum alloy is selected from the group consisting of aluminum, copper, chromium,

in step S3, the diameter of the preheated aluminum alloy cast rod is 377-378 mm.

4. The process of claim 1, wherein the aluminum alloy is selected from the group consisting of aluminum, copper, chromium,

in the step S4, a 45MN forward extruder is adopted to extrude the aluminum alloy cast rod, the extrusion coefficient is 12-13, the discharging speed is 3.0-4.0 m/min, and a tractor is adopted to synchronously pull in the discharging process;

the extrusion die parameters were as follows: the diameter is 360mm, and thickness is 220mm, and the feed inlet diameter is 150 ~ 160mm, and the degree of depth is 50 ~ 60mm, and the bearing metering feed inlet inclination is 2.5 ~ 3, and length is 8 ~ 10mm, and bearing metering length is 8 ~ 10mm, and the one-level air knife is 1.5 ~ 2 mm.

5. The process of claim 1, wherein the aluminum alloy is selected from the group consisting of aluminum, copper, chromium,

in step S5, the conductivity of the circulating water is less than or equal to 300us/cm³The water temperature is less than or equal to 38 ℃, and the water pressure is 0.4-0.5 MPa.

6. The process of claim 1, wherein the aluminum alloy is selected from the group consisting of aluminum, copper, chromium,

in step S7, the product obtained after sawing in step S6 is subjected to solution heat treatment at 540-550 ℃ for 1-2 h, and subjected to aging heat treatment at 170-180 ℃ for 6-8 h.

7. An aluminum alloy block produced by the process for producing a high performance fine-grained zero-macrocrystalline aluminum alloy according to any one of claims 1 to 6.

8. Use of an aluminium alloy block according to claim 7 in swing arms of automobiles.

Technical Field

The invention belongs to the technical field of Al-Mg-Si series aluminum alloy preparation, and particularly relates to a high-performance fine-grain zero-coarse-grain ring aluminum alloy, and a preparation process and application thereof.

Background

At present, industrial aluminum alloy extruded sections have many different requirements, such as higher mechanical properties, excellent machinability, better material ductility, fine grain size and shallower surface recrystallization layer, good surface quality and the like, according to the final use of the material. Therefore, research materials can finally meet the higher and higher use requirements of customers, and become an important subject of the research on the chemical composition of the aluminum alloy. The aluminum alloy product in the existing automobile swing arm is easy to generate a coarse crystal ring, so that the problems of strength reduction, poor mechanical property and the like of an aluminum alloy material are caused, and the normal use of the material is influenced.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide a preparation process of a high-performance fine-grain zero-coarse-grain ring aluminum alloy. In order to achieve the technical purpose, the embodiment of the invention adopts the technical scheme that:

in a first aspect, an embodiment of the present invention provides a preparation process of a high-performance fine-grain zero-coarse-grain ring aluminum alloy, including the following steps:

step S1, casting aluminum ingots: selecting an aluminum alloy raw material to carry out smelting casting, and casting in a vacuum direct cooling casting system at the speed of 36-40 mm/min during casting to obtain an aluminum alloy casting rod;

the aluminum alloy raw material comprises the following components in percentage by mass: silicon: 1.0-1.1%, iron: 0.1-0.2%, copper: 0.45-0.55%, manganese: 0.6-0.7%, magnesium: 0.8 to 0.85%, chromium: 0.1 to 0.2% and titanium: 0.15 to 0.2 percent of aluminum and inevitable impurities as the rest;

step S2, homogenization: homogenizing the aluminum alloy cast rod obtained in the step S1 at 490-510 ℃ for 9-11 h, and cooling the aluminum alloy cast rod to room temperature after homogenizing;

step S3, preheating: respectively preheating the aluminum alloy cast rod, the extrusion die and the die cylinder which are homogenized in the step S2;

step S4, extrusion: extruding the preheated cast rod preheated in the step S3 by using an extruder;

step S5, quenching: carrying out on-line water penetration quenching on the product extruded in the step S4, wherein the quenching medium is circulating water;

step S6, straightening: straightening and sawing the product quenched and cooled in the step S5, wherein the straightening rate is 0.3-1.0%;

step S7, artificial solid solution and time-effect heat treatment: and (5) carrying out artificial solution heat treatment and aging heat treatment on the product sawn in the step S6.

Specifically, in the step S3, the preheating temperature of the aluminum alloy cast rod is 480-500 ℃, and the head-tail temperature gradient of the cast rod is 10-20 ℃; the preheating temperature of the extrusion die is 470-490 ℃; the preheating temperature of the die cylinder is 425-435 ℃.

Specifically, in step S3, the diameter of the preheated aluminum alloy cast rod is 377-378 mm.

Specifically, in step S4, a 45MN forward extruder is used for extruding the aluminum alloy cast rod, the extrusion coefficient is 12-13, the discharging speed is 3.0-4.0 m/min, and a tractor is used for synchronous traction in the discharging process.

Preferably, the extrusion die parameters are as follows: the diameter is 360mm, and thickness is 220mm, and the feed inlet diameter is 150 ~ 160mm, and the degree of depth is 50 ~ 60mm, and the bearing metering feed inlet inclination is 2.5 ~ 3, and length is 8 ~ 10mm, and bearing metering length is 8 ~ 10mm, and the one-level air knife is 1.5 ~ 2 mm.

Specifically, in step S5, the conductivity of the circulating water is less than or equal to 300us/cm³The water temperature is less than or equal to 38 ℃, and the water pressure is 0.4-0.5 MPa.

Specifically, in step S7, the sawn product obtained in step S6 is subjected to solution heat treatment at 540-550 ℃ for 1-2 h, and subjected to aging heat treatment at 170-180 ℃ for 6-8 h.

In a second aspect, the embodiment of the invention also provides an aluminum alloy product prepared by the preparation process.

In a third aspect, the embodiment of the invention also provides application of the aluminum alloy product prepared by the preparation process in automobile swing arms.

The technical scheme provided by the embodiment of the invention has the following beneficial effects:

according to the embodiment of the invention, preheating is carried out before the extrusion step of the aluminum alloy cast rod, and parameter improvement design is carried out on the extrusion die, so that the phenomenon that outer-layer crystal nuclei grow rapidly to form coarse crystal rings due to friction heat in the extrusion process is avoided; the aluminum alloy product prepared by the preparation process provided by the embodiment of the invention has high strength, fine grains and no coarse grain ring, the tensile strength is 400-430 MPa, the yield strength is 380-400 MPa, the elongation is 10-13%, the grain grade index reaches 6-8 grade, and the product has no coarse grain ring, so that an excellent material is provided for subsequent processing of customers.

Drawings

FIG. 1 is a flow chart of a preparation process of the high-performance fine-grain zero-coarse-grain ring aluminum alloy of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The embodiment of the invention provides a preparation process of a high-performance fine-grain zero-coarse-grain ring aluminum alloy, which comprises the following steps:

step S1, casting aluminum ingots: selecting an aluminum alloy raw material to carry out smelting casting, and casting in a vacuum direct cooling casting system at a speed of 36-40 mm/min during casting, wherein the casting speed can be 36mm/min, 37mm/min, 38mm/min, 39mm/min and 40mm/min, for example, so as to obtain an aluminum alloy cast rod;

the aluminum alloy raw material comprises the following components in percentage by mass: silicon: 1.0 to 1.1%, for example, 1.0%, 1.02%, 1.04%, 1.06%, 1.08%, 1.1%, etc., iron: 0.1 to 0.2%, for example, 0.1%, 0.12%, 0.14%, 0.16%, 0.18%, 0.2%, etc., copper: 0.45 to 0.55%, for example, 0.45%, 0.47%, 0.49%, 0.51%, 0.53%, 0.55%, etc., manganese: 0.6 to 0.7%, for example, 0.6%, 0.62%, 0.64%, 0.66%, 0.68%, 0.7%, etc., magnesium: 0.8-0.85%, chromium: 0.1 to 0.2%, for example, 0.1%, 0.12%, 0.14%, 0.16%, 0.18%, 0.2%, etc., titanium: 0.15 to 0.2%, for example, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.2%, etc., with the balance being aluminum and inevitable impurities;

step S2, homogenization: homogenizing the aluminum alloy cast rod obtained in the step S1 at 490-510 ℃ for 9-11 h, for example, 490 ℃, 495 ℃, 500 ℃, 505 ℃, 510 ℃ and the like, homogenizing for 9h, 9.5h, 10h, 10.5h, 11h and the like, and cooling the aluminum alloy cast rod to room temperature after homogenizing; (ii) a

Step S3, preheating: respectively preheating the aluminum alloy cast rod, the extrusion die and the die cylinder which are homogenized in the step S2;

step S4, extrusion: extruding the preheated cast rod preheated in the step S3 by using an extruder;

step S5, quenching: carrying out on-line water penetration quenching on the product extruded in the step S4, wherein the quenching medium is circulating water;

step S6, straightening: straightening and sawing the product quenched and cooled in the step S5, wherein the straightening rate is 0.3-1.0%, for example, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0% and the like;

step S7, artificial solid solution and time-effect heat treatment: and (5) carrying out artificial solution heat treatment and aging heat treatment on the product sawn in the step S6.

Specifically, in step S3, the preheating temperature of the aluminum alloy cast rod is 480 to 500 ℃, for example 480 ℃, 485 ℃, 490 ℃, 495 ℃, 500 ℃ and the like, and the head-to-tail temperature gradient of the cast rod is 10 to 20 ℃, for example 10 ℃, 12 ℃, 14 ℃, 16 ℃, 18 ℃, 20 ℃ and the like; the preheating temperature of the extrusion die is 470-490 ℃; for example, 470 ℃, 475 ℃, 480 ℃, 485 ℃, 490 ℃ and the like can be used, and the preheating temperature of the die cylinder is 425-435 ℃, for example, 425 ℃, 427 ℃, 430 ℃, 432 ℃, 435 ℃ and the like can be used.

Specifically, in step S3, the diameter of the preheated aluminum alloy cast rod is 377-378 mm, and may be, for example, 377.0mm, 377.2mm, 377.4mm, 377.6mm, 377.8mm, 378mm, and the like.

Specifically, in step S4, a 45MN forward extruder is used to extrude the aluminum alloy cast bar, the extrusion coefficient is 12 to 13, for example, 12.0, 12.2, 12.4, 12.6, 12.8, 13, etc., the discharge speed is 3.0 to 4.0m/min, for example, 3.0m/min, 3.2m/min, 3.4m/min, 3.6m/min, 3.8m/min, 4.0m/min, etc., and a tractor is used to synchronously draw in the discharge process.

Preferably, the extrusion die parameters are as follows: the diameter is 360mm, the thickness is 220mm, the diameter of the feed inlet is 150-160 mm, such as 150.0mm, 150.2mm, 150.4mm, 150.6mm, 150.8mm, 160mm, etc., the depth is 50-60 mm, such as 50.0mm, 50.2mm, 50.4mm, 50.6mm, 50.8mm, 60mm, etc., the inclination of the feed inlet of the bearing belt is 2.5-3 °, such as 2.5 °, 2.6 °, 2.7 °, 2.8 °, 2.9 °, 3.0 °, etc., the length is 8-10 mm, such as 8.0mm, 8.5mm, 9.0mm, 9.5mm, 10.0mm, etc., the length of the bearing belt is 8-10 mm, such as 8.0mm, 8.5mm, 9.0mm, 10.0mm, etc., and the primary blank cutter is 1.5-2 mm, such as 1.5mm, 1.7mm, 1.0 mm, etc.

Specifically, in step S5, the conductivity of the circulating water is less than or equal to 300us/cm³The water temperature is less than or equal to 38 ℃, and the water pressure is 0.4-0.5 MPa, such as 0.4MPa, 0.45MPa, 0.5MPa and the like.

Specifically, in step S7, the product obtained after sawing in step S6 is subjected to solution heat treatment at 540 to 550 ℃ for 1 to 2 hours, for example, at 540 ℃, 542 ℃, 544 ℃, 546 ℃, 548 ℃, 550 ℃, for example, for 1.0 hour, 1.2 hours, 1.4 hours, 1.5 hours, 1.6 hours, 1.8 hours, 2.0 hours, and the like, and subjected to aging heat treatment at 170 to 180 ℃ for 6 to 8 hours, for example, at 170 ℃, 172 ℃, 174 ℃, 175 ℃, 176 ℃, 178 ℃, 180 ℃, for example, for 6.0 hours, 6.5 hours, 7.0 hours, 7.5 hours, 8.0 hours, and the like.

In a second aspect, the embodiment of the invention also provides an aluminum alloy product prepared by the preparation process.

In a third aspect, the embodiment of the invention also provides application of the aluminum alloy product prepared by the preparation process in automobile swing arms.

Example 1

A preparation process of a high-performance fine-grain zero-coarse-grain ring aluminum alloy comprises the following steps:

step S1, casting the aluminum ingot, and smelting the aluminum ingot according to the following formula ratio in percentage by mass: silicon: 1.05%, iron: 0.15%, copper: 0.5%, manganese: 0.65%, magnesium: 0.83%, chromium: 0.15%, titanium: 0.17%, the balance being aluminum and inevitable impurities;

casting by a vacuum direct cooling casting system at the speed of 36mm/min to obtain an aluminum alloy cast rod;

step S2, homogenization: homogenizing the cast rod obtained in the step S1 at 490 ℃ for 11h, and cooling the cast rod to room temperature after homogenization treatment;

step S3, preheating: respectively preheating the cast rod, the extrusion die and the die cylinder which are obtained after the homogenization in the step S2; the preheating temperature of the casting rod is set to be 480 ℃, the temperature gradient of the head and the tail of the casting rod is 10 ℃, the preheating temperature of the extrusion die is set to be 470 ℃, and the preheating temperature of the die cylinder is set to be 425 ℃.

Step S4, extrusion: the cast rod heated in the step S3 is extruded by adopting a 45MN forward extruder, the diameter of the cast rod before extrusion is 377mm, the extrusion coefficient is 12, the discharging speed is 3.0m/min, a tractor is adopted to synchronously pull in the discharging process, and the adopted parameters of an extrusion die are as follows: the diameter is 360mm, and thickness is 220mm, and the feed inlet diameter is 150mm, and the degree of depth is 50mm, and the bearing belt feed inlet inclination is 2.5, and length is 8mm, and bearing belt length is 8mm, and the one-level air knife is 1.5 mm.

Step S5, quenching: performing on-line water penetration quenching on the product extruded in the step S4, wherein the quenching medium is circulating water, and the conductivity of the circulating water is 300us/cm³The water temperature is 38 ℃ and the water pressure is 0.4 MPa.

Step S6, straightening: straightening and sawing the product after on-line quenching, wherein the straightening rate is 0.3%;

step S7, artificial solid solution and time-effect heat treatment: and (3) carrying out solution heat treatment on the product obtained after sawing in the step S6 at 540 ℃ for 2h, and carrying out aging heat treatment at 170 ℃ for 8 h.

Example 2

A preparation process of a high-performance fine-grain zero-coarse-grain ring aluminum alloy comprises the following steps:

step S1, casting the aluminum ingot, and smelting the aluminum ingot according to the following formula ratio in percentage by mass: silicon: 1.05%, iron: 0.15%, copper: 0.5%, manganese: 0.65%, magnesium: 0.83%, chromium: 0.15%, titanium: 0.17%, the balance being aluminum and inevitable impurities;

casting at 40mm/min by using a vacuum direct cooling casting system to obtain a cast rod;

step S2, homogenization: the cast bar obtained in step S1 was homogenized at 510 ℃ for 9 hours,

step S3, preheating: respectively preheating the cast rod, the extrusion die and the die cylinder which are obtained after the homogenization in the step S2; the preheating temperature of the casting rod is set to be 500 ℃, the temperature gradient of the head and the tail of the casting rod is 20 ℃, the preheating temperature of the extrusion die is set to be 490 ℃, and the preheating temperature of the die cylinder is set to be 435 ℃.

Step S4, extrusion: and (2) extruding the cast rod heated in the step S3 by using a 45MN forward extruder, wherein the diameter of the cast rod is 378mm, the extrusion coefficient is 13, the discharging speed is 4.0m/min, the discharging process adopts a tractor for synchronous traction, and the adopted extrusion die parameters are as follows: the diameter is 360mm, and thickness is 220mm, and the feed inlet diameter is 160mm, and the degree of depth is 60mm, and bearing belt feed inlet inclination is 3, and length is 10mm, and bearing belt length is 10mm, and the one-level air knife is 2 mm.

Step S5, quenching: performing on-line water penetration quenching on the product extruded in the step S4, wherein the quenching medium is circulating water, and the conductivity of the circulating water is 300us/cm³The water temperature is 38 ℃ and the water pressure is 0.5 MPa.

Step S6, straightening: straightening and sawing the product after on-line quenching, wherein the straightening rate is 1.0%;

step S7, artificial solution aging heat treatment: and (4) carrying out solution heat treatment on the product obtained after sawing in the step S6 at 550 ℃ for 1h, and carrying out aging heat treatment at 180 ℃ for 6 h.

Example 3

A preparation process of a high-performance fine-grain zero-coarse-grain ring aluminum alloy comprises the following steps:

step S1, casting the aluminum ingot, and smelting the aluminum ingot according to the following formula ratio in percentage by mass: silicon: 1.05%, iron: 0.15%, copper: 0.5%, manganese: 0.65%, magnesium: 0.83%, chromium: 0.15%, titanium: 0.17%, the balance being aluminum and inevitable impurities;

casting at the speed of 38mm/min by adopting a vacuum direct cooling casting system to obtain a cast rod;

step S2, homogenization: homogenizing the cast rod obtained in the step S1 at 500 ℃ for 10h,

step S3, preheating: respectively preheating the cast rod, the extrusion die and the die cylinder which are obtained after the homogenization in the step S2; the preheating temperature of the casting rod is set to 490 ℃, the temperature gradient of the head and the tail of the casting rod is 15 ℃, the preheating temperature of the extrusion die is set to 480 ℃, and the preheating temperature of the die cylinder is set to 430 ℃.

Step S4, extrusion: the cast rod heated in the step S3 is extruded by adopting a 45MN forward extruder, the diameter of the cast rod before extrusion is 377.5mm, the extrusion coefficient is 12.5, the discharging speed is 3.5m/min, a tractor is adopted to synchronously pull in the discharging process, and the adopted parameters of an extrusion die are as follows: the diameter is 360mm, thickness is 220mm, and the feed inlet diameter is 155mm, and the degree of depth is 55mm, and the bearing belt feed inlet inclination is 2.7, and length is 9mm, and bearing belt length is 9mm, and first-order blank sword is 1.7 mm.

Step S5, quenching: performing on-line water penetration quenching on the product extruded in the step S4, wherein the quenching medium is circulating water, and the conductivity of the circulating water is 300us/cm³The water temperature is 38 ℃ and the water pressure is 0.45 MPa.

Step S6, straightening: straightening and sawing the product after on-line quenching, wherein the straightening rate is 0.6%;

step S7, artificial solid solution and time-effect heat treatment: and carrying out solution heat treatment on the product obtained after sawing in the step S6 at 545 ℃ for 1.5h, and carrying out aging heat treatment at 175 ℃ for 7 h.

Application examples

This application example evaluates the tensile strength, yield strength, elongation, and internal grain size grades of the aluminum alloy blocks provided in examples 1 to 3. Specifically, the finished aluminum alloys obtained in examples 1 to 3 were selected as test specimens of the same quality, and the tensile strength, yield strength and elongation of 3 test specimens were measured according to the method provided by the "test specimens and methods for tensile test of processed products of wrought aluminum, magnesium and alloys thereof" standard, and according to the "part 1 of the method for texture testing of wrought aluminum and aluminum alloy products of GB/T3246.1: microstructural inspection method the internal grain size rating of 3 samples was tested as provided by the standard. Specific test parameters for the aluminum alloy blocks produced in examples 1-3 are detailed in Table 1 below.

Table 1 examples 1-3 various performance test tables

Aluminum alloy block	Tensile strength MPa	Yield strength MPa	Elongation percentage%	Internal grain size rating
					Example 1	411	386	12.2	7.3
Example 2	419	391	11.1	6.8
					Example 3	425	395	10.4	7.1

As can be seen from Table 1, the aluminum alloy blocks provided in examples 1 to 3 have high tensile strength and yield strength, high elongation, internal grain size grades of 6 to 8 grades, no coarse grain rings, excellent product performance and capability of meeting the use requirements.

Finally, it should be noted that the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to examples, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the claims of the present invention.