CN106735080B

CN106735080B - Continuous extrusion die for aluminum pipe

Info

Publication number: CN106735080B
Application number: CN201710030487.1A
Authority: CN
Inventors: 王诗绮; 王永明
Original assignee: Henan Mingruida Machinery Manufacturing Co ltd
Current assignee: Henan Mingruida Machinery Manufacturing Co ltd
Priority date: 2017-01-10
Filing date: 2017-01-17
Publication date: 2021-06-01
Anticipated expiration: 2037-01-17
Also published as: CN106735080A

Abstract

The invention provides a continuous extrusion die for an aluminum pipe, which comprises a male die, a female die and a forming core rod arranged on the male die, wherein the female die comprises a female die base body, a forming gasket and a female die forming through hole, the female die base body is internally provided with a reverse frustum-shaped female die forming cavity, the forming gasket is arranged on the inner side of the bottom of the female die base body, the female die forming through hole penetrates through the bottom of the female die and the forming gasket, the forming core rod and the forming gasket respectively comprise a hard alloy base body and a nano titanium nitride layer, a nano titanium carbide layer or a nano titanium carbonitride layer deposited on the hard alloy base body, and the hard alloy is titanium niobium molybdenum carbide alloy, titanium niobium molybdenum nitride alloy. The surface roughness Ra value of the hard alloy matrix is 0.01-0.1. The aluminum pipe continuous extrusion die has high red hardness, high surface gloss and high-temperature corrosion resistance, so that the die has long service life.

Description

Continuous extrusion die for aluminum pipe

Technical Field

The invention relates to the technical field of dies, in particular to an aluminum pipe continuous extrusion die.

Background

Seamless tubular metal products are typically produced in bulk by an extrusion process, and during the extrusion process, the dimensional stability of the die forming components and the surface finish of the die forming components can have a significant effect on the size and finish of the tubular metal product. The existing forming part causes great economic loss because the mould is frequently maintained and even directly scrapped due to the reduction of the size or the surface finish of the forming part after continuous high-temperature use. For example, in the existing aluminum pipe continuous extrusion die, when an aluminum pipe with a pipe outer diameter of 7.5mm and a pipe wall thickness of 0.7mm is produced, about 10 tons of aluminum liquid can only be processed into the aluminum pipe, the aluminum pipe continuous extrusion die reaches the scrappage degree due to dimensional tolerance, and polishing treatment needs to be carried out on a die forming part every time 1-2 tons of aluminum liquid are processed in the production process. In order to prolong the service life of the die, a wear-resistant layer is usually deposited on the surface of a forming part of the die by a thermal deposition method or an electroplating method, but because the bonding force between the wear-resistant layer and a substrate is not firm, the bonding force between the wear-resistant layer and the substrate is weak due to poor wettability of the wear-resistant layer and the substrate, and the wear-resistant layer is difficult to form a tightly-bonded interface coating with the substrate and is easy to fall off; and the aluminum pipe continuous extrusion die with the common coating deposited on the surface of the die has short service life, and only processes about 20 to 30 percent more aluminum liquid than the die without the coating.

In order to solve the above problems, people are always seeking an ideal technical solution.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, and provides the continuous extrusion die for the aluminum pipe, which has stronger interlayer bonding force, better wear resistance and corrosion resistance and better thermal stability.

In order to achieve the purpose, the invention adopts the technical scheme that: a continuous extrusion die for aluminum pipes comprises a male die and a female die, wherein a forming core rod is arranged on the male die, the female die comprises a female die base body, a forming gasket and a female die forming through hole, the female die base body is internally provided with an inverted frustum-shaped female die forming cavity, the forming gasket is arranged at the center of the inverted frustum-shaped female die forming cavity, the female die forming through hole penetrates through the female die base body and the forming gasket,

the forming core rod comprises a forming core rod substrate made of hard alloy and a wear-resistant corrosion-resistant coating deposited on the forming core rod substrate; the forming gasket comprises a forming gasket base body which is made of the same material as the forming core rod base body and the wear-resistant corrosion-resistant coating deposited on the forming gasket base body;

the wear-resistant corrosion-resistant coating is a nano titanium nitride layer, a nano titanium carbide layer or a nano titanium carbonitride layer, the hard alloy is titanium carbide niobium molybdenum alloy, titanium nitride niobium molybdenum alloy or tungsten titanium alloy, and the tungsten titanium alloy comprises the following components in percentage by mass: 78-85% of WC, 5-15% of TiC and 6-10% of Co;

the surface roughness Ra values of the forming core rod substrate and the forming gasket substrate are both 0.01-0.1.

Based on the above, the tungsten-titanium alloy composition further includes NbC or TaC, and the tungsten-titanium alloy matrix containing NbC or TaC has a mass percent of WC of 82% to 85%, a mass percent of TiC of 6%, a mass percent of Co of 6% to 8%, and the balance NbC or TaC.

Based on the above, the thickness of the wear-resistant and corrosion-resistant coating is 5 to 10 micrometers.

Based on the above, the thickness of the formed gasket is 3 mm to 8 mm.

Based on the above, the male die comprises a male die base body, a male die forming boss and at least two shunting grooves penetrating through the male die forming boss and the male die base body, the male die base body and the male die forming boss are integrally arranged, the outer end face of the male die forming boss is provided with an assembly blind hole, the male die forming boss is matched with the inverted frustum-shaped female die forming cavity to form an aluminum liquid circulation channel,

the forming core rod base body comprises an installation handle and a forming inner core matched with the female die forming through hole, the installation handle and the forming inner core are integrally arranged, the installation handle is arranged in the assembling blind hole, and the installation handle is in interference fit with the assembling blind hole; the specific installation method is to assemble the installation handle in the assembly blind hole by adopting a hot-assembling method.

Based on the above, the cross section of the sizing inner core is circular, triangular or polygonal.

Based on the above, the cross section of the female die forming through hole is circular, triangular or polygonal which is matched with the shaping inner core.

Basically, the forming end of the shaping inner core is in the shape of a long strip, and the cross section of the female die forming through hole is a long round hole matched with the shaping inner core.

Based on the above, the forming core rod is prepared by the following method:

firstly, the hard alloy material containing the components in percentage by mass is selected to be processed to prepare a forming core rod blank,

then, grinding and polishing the forming core rod blank to enable the surface roughness Ra of the forming core rod blank to be 0.04-0.1, and obtaining a polishing forming core rod blank; degreasing and deoiling the polished forming core rod blank to obtain the forming core rod substrate with a clean surface;

then, a chemical deposition method is adopted to deposit a wear-resistant corrosion-resistant coating with the thickness of 5-10 microns on the forming core rod substrate with a clean surface by taking nano titanium nitride, nano titanium carbide or nano titanium carbonitride as raw materials;

and finally, carrying out finish polishing on the wear-resistant corrosion-resistant coating by adopting a fluid polishing method to ensure that the surface roughness Ra of the wear-resistant corrosion-resistant coating is 0.01-0.04, and preparing the forming core rod.

Based on the above, the molded gasket is prepared by the following method:

firstly, the hard alloy material containing the components in percentage by mass is selected to be processed to prepare a formed gasket blank,

then, grinding and polishing the forming pad blank to enable the surface roughness Ra of the forming pad blank to be 0.04-0.1, and obtaining a polishing forming pad blank; degreasing and deoiling the polishing forming gasket blank to obtain the forming gasket base body with a clean surface;

then, depositing the wear-resistant corrosion-resistant coating with the thickness of 5-10 microns on the forming gasket substrate with the clean surface by using nano titanium nitride, nano titanium carbide or nano titanium carbonitride as a raw material by adopting a chemical deposition method;

and finally, carrying out fine polishing on the wear-resistant and corrosion-resistant coating by adopting a fluid polishing method to ensure that the surface roughness Ra of the wear-resistant and corrosion-resistant coating is 0.01-0.04, and thus obtaining the formed gasket.

In order to ensure the processing dimensional stability of the manufactured forming core rod and the forming pad and improve the grinding and polishing efficiency, when grinding and polishing treatment is carried out on the forming core rod blank and the forming pad blank, firstly, grinding equipment with the mesh number of 100-500 is selected for carrying out rough machining on the forming core rod blank and the forming pad blank, then, grinding equipment with the mesh number of 1000-3000 is selected for carrying out fine machining, finally, the surface roughness Ra value of the forming core rod blank and the forming pad blank is 0.04-0.1, a Swon abrasive particle fluid polishing machine is adopted for polishing the wear-resistant and corrosion-resistant coating, and the surface roughness Ra value of the wear-resistant and corrosion-resistant coating is polished to 0.01-0.04.

Specifically, when the forming die for the wear-resistant and corrosion-resistant coating is in an assembly state, the inverted frustum-shaped female die forming cavity is matched with the male die forming boss to form a liquid circulation channel, and the sizing inner core is matched with the female die forming through hole to determine the thickness of the tube wall. Molten aluminum firstly enters the female die forming cavity through the shunting groove, so that the aluminum liquid is uniformly mixed, then flows into the female die forming through hole, and is shaped through the assembling and matching between the shaping inner core and the female die forming through hole, so that the thin-wall aluminum pipe with certain wall thickness and certain pipe diameter is prepared.

According to the invention, titanium carbide niobium molybdenum alloy, titanium nitride niobium molybdenum alloy or tungsten titanium alloy materials are selected as raw materials of a forming part consisting of a forming gasket and the forming gasket in the aluminum pipe continuous extrusion die, the high corrosion resistance, high-temperature dimensional stability and good red hardness of the hard alloy are utilized, the dimensional stability and good high-temperature corrosion resistance of the forming part of the aluminum pipe continuous extrusion die are ensured, and meanwhile, the hard alloy material has small grain size, so that the forming part of the aluminum pipe continuous extrusion die can obtain a surface with low surface roughness after grinding and polishing treatment.

Furthermore, a nano titanium nitride layer, a nano titanium carbide layer or a nano titanium carbonitride layer is deposited on the surfaces of the forming core rod matrix and the forming gasket matrix, and the bonding force between the wear-resistant corrosion-resistant coating and the forming core rod matrix and the forming gasket matrix is improved by utilizing the same element diffusion effect of titanium elements existing in the wear-resistant corrosion-resistant coating, the forming core rod matrix and the forming gasket matrix together, so that the interface coating tightly bonded between the wear-resistant corrosion-resistant coating and the two matrixes is not easy to fall off. More importantly, the wear-resistant corrosion-resistant coating is prepared by taking nano-scale titanium nitride, titanium carbide or nano-scale titanium carbonitride as raw materials and utilizing the nano effect of nano particles, so that the prepared wear-resistant corrosion-resistant coating has higher glossiness and lower friction coefficient, thereby greatly reducing the friction force between a forming part of an aluminum pipe continuous extrusion die and aluminum liquid, ensuring that the aluminum liquid is not easy to adhere and accumulate on the forming part of the aluminum pipe continuous extrusion die in the production process of the aluminum pipe and ensuring that the surface of the prepared aluminum pipe is smooth and has no scratches.

Furthermore, the wear-resistant corrosion-resistant coating takes nano titanium nitride, nano titanium carbide or nano titanium carbonitride as raw materials, so that the hardness of the prepared wear-resistant corrosion-resistant coating is higher than that of the forming core rod matrix and the forming gasket matrix, and simultaneously, the wear-resistant corrosion-resistant coating has high oxidation resistance, better adhesion resistance, higher wear resistance and better crater wear resistance, so that the size stability, the high-temperature corrosion resistance and the high-temperature wear resistance of a forming part in the aluminum pipe continuous extrusion die are obviously improved, and the service life of the aluminum pipe continuous extrusion die is obviously prolonged. For example, when the aluminum pipe continuous extrusion die is used for producing a thin-wall aluminum pipe with a pipe outer diameter of 7.5mm and a pipe wall thickness of 0.7mm, about 40 tons of aluminum liquid can be continuously processed, and the dimensional qualification rate of the prepared thin-wall aluminum pipe reaches more than 99%.

Drawings

FIG. 1 is a schematic view showing the structure of the outer side of a male die of an aluminum pipe extrusion molding die provided in example 1 of the present invention.

FIG. 2 is a schematic view showing the inside structure of a male die of an aluminum pipe extrusion molding die provided in example 1 of the present invention.

Fig. 3 and 4 are schematic views of the structure of the forming mandrel for an aluminum pipe extrusion die provided in example 1 of the present invention.

FIG. 5 is a schematic view showing the inside structure of a female die of an aluminum pipe extrusion molding die provided in example 1 of the present invention.

FIG. 6 is a schematic view showing the outer side structure of a female die of an aluminum pipe extrusion molding die provided in example 1 of the present invention.

FIG. 7 is a schematic perspective sectional view of a female die of an aluminum pipe extrusion molding die provided in example 1 of the present invention.

Fig. 8 is a schematic structural view of a gasket for forming an aluminum pipe extrusion mold according to embodiment 1 of the present invention.

FIG. 9 is a schematic view showing the structure of the inside of the male die of the aluminum pipe extrusion molding die provided in example 5 of the present invention.

FIG. 10 is a schematic view showing the inside structure of a female die of an aluminum pipe extrusion molding die provided in example 5 of the present invention.

In the figure: 1. a male die substrate; 2. a shunt slot; 3. forming a core rod; 31. shaping the inner core; 32. a handle is installed; 34. forming a core rod substrate; 35. a wear-resistant corrosion-resistant coating; 4. forming a boss by using a male die; 5. a female die matrix; 6. forming a through hole by using a female die; 7. forming a cavity by using a female die; 8. forming a gasket; 9. a molding gasket mounting groove; 81. and forming the gasket base body.

Detailed Description

The technical solution of the present invention is further described in detail by the following embodiments.

Example 1

The embodiment provides an aluminum pipe extrusion forming die which specifically comprises a male die, a female die and a forming core rod 3 arranged on the male die.

As shown in fig. 1 and 2, the male die comprises a cylindrical male die base body 1, a male die forming boss 4 and three shunt grooves 2 penetrating through the male die forming boss 4 and the male die base body 1. The cylindrical male die base body 1 and the male die forming boss 4 are integrally arranged, and an assembly blind hole is formed in the center of the outer end face of the male die forming boss 4.

As shown in fig. 3 and 4, the forming mandrel 3 includes a forming mandrel base 34 and a wear-resistant corrosion-resistant coating 35 deposited on the surface of the forming mandrel base 34. The wear-resistant corrosion-resistant coating 35 is a nano titanium nitride coating, and the thickness of the nano titanium nitride coating is 5 microns. The forming core rod substrate 34 is processed by an alloy material comprising the following components in percentage by mass: 85% of WC, 6% of TiC, 6% of Co and 3% of NbC. Since the coating thickness in this embodiment is extremely thin, the forming mandrel base body 34 is required to have a low surface roughness in order to ensure a high surface finish of the coating surface, and preferably has a surface roughness Ra value of 0.05.

According to the functional distinction, the specific structure of the forming core rod base body 34 can be divided into a shaping inner core 31 and an installation handle 32 which are integrally arranged and have a circular cross section. The installation handle 32 is arranged in the assembly blind hole, the installation handle 32 is in interference fit with the assembly blind hole, and the installation handle is assembled in the assembly blind hole by adopting a hot-assembling method.

The forming mandrel 3 provided by the embodiment is prepared by the following method:

then grinding and polishing the forming core rod blank to enable the surface roughness Ra of the forming core rod blank to be 0.05, and obtaining a polishing forming core rod blank; degreasing and deoiling the polished forming core rod blank to obtain a forming core rod substrate with a clean surface; in order to ensure the processing dimensional stability of the manufactured forming core rod matrix and improve the grinding and polishing efficiency, when grinding and polishing are carried out on the forming core rod blank, firstly, 100-500-mesh grinding equipment is selected to carry out rough machining on the forming core rod blank, then, 1000-3000-mesh grinding equipment is selected to carry out fine machining on the roughly machined forming core rod blank, and finally, the surface roughness Ra value of the forming core rod blank is 0.05;

and then, using nano titanium nitride as a raw material by adopting a chemical deposition method, depositing a wear-resistant corrosion-resistant coating with the thickness of 5 microns on the outer surface of the forming core rod substrate with a clean surface, and finally, performing finish polishing on the wear-resistant corrosion-resistant coating by adopting a fluid polishing method to ensure that the surface roughness Ra of the wear-resistant corrosion-resistant coating is 0.03, thus preparing the forming core rod.

As shown in fig. 5 and 6, the die comprises a die base body 5 with an inverted frustum-shaped die forming cavity 7 formed therein, a forming gasket 8 arranged at the center of the inverted frustum-shaped die forming cavity 7 and a die forming through hole 6 penetrating through the die base body 5 and the forming gasket 8, and the thickness of the forming gasket is 5 millimeters. Specifically, as shown in fig. 7 and 8, a forming gasket mounting groove 9 is formed in the center of the inverted frustum-shaped female die forming cavity 7, and the forming gasket 8 is assembled in the forming gasket mounting groove 9 by a hot-assembling method. The forming gasket 8 comprises a forming gasket base 81 which is made of the same material as the forming mandrel base 34 and the wear-resistant corrosion-resistant coating 35 deposited on the forming gasket base 81.

The molded gasket provided by the embodiment is prepared by the following method:

then grinding and polishing the forming pad blank to enable the surface roughness Ra of the forming pad blank to be 0.05, and obtaining a polishing forming pad blank; degreasing and deoiling the polishing forming gasket blank to obtain the forming gasket base body with a clean surface;

then, depositing the wear-resistant corrosion-resistant coating with the thickness of 5 microns on the forming gasket substrate with the clean surface by using nano titanium nitride, nano titanium carbide or nano titanium carbonitride as a raw material by adopting a chemical deposition method; and finally, carrying out fine polishing on the wear-resistant and corrosion-resistant coating by adopting a fluid polishing method to ensure that the surface roughness Ra of the wear-resistant and corrosion-resistant coating is 0.03, thus preparing the formed gasket.

Specifically, when the forming die of the wear-resistant corrosion-resistant coating is in an assembly state, the inverted frustum-shaped female die forming cavity 7 and the male die forming boss 4 are matched to form a liquid circulation channel, and the sizing inner core 31 and the female die forming through hole 6 are matched to determine the thickness of the tube wall. Molten aluminum firstly enters the female die forming cavity 7 through the three shunting grooves 2, so that the molten aluminum is uniformly mixed, then flows into the female die forming through hole 6, and is shaped through the assembling and matching between the shaping inner core 31 and the female die forming through hole 6, so that the thin-wall aluminum pipe with certain wall thickness and certain pipe diameter is prepared.

In the embodiment, a hard alloy material containing 85% of WC, 6% of TiC, 6% of Co and 3% of NbC is selected as a forming part consisting of a forming gasket and a forming gasket in the aluminum pipe continuous extrusion die, the high corrosion resistance, the high-temperature dimensional stability and the good red hardness of the hard alloy are utilized, the dimensional stability and the good high-temperature corrosion resistance of the forming part of the aluminum pipe continuous extrusion die are ensured, and meanwhile, the alloy material has a small grain size, so that the forming part of the aluminum pipe continuous extrusion die can obtain a surface with low surface roughness through grinding and polishing treatment.

Further, in this embodiment, a layer of nano titanium nitride layer is deposited on the surface of each of the forming mandrel substrate and the forming gasket substrate, and the bonding force between the wear-resistant corrosion-resistant coating and the forming mandrel substrate and the forming gasket substrate is improved by using the same element diffusion effect of the titanium elements existing in the wear-resistant corrosion-resistant coating, the forming mandrel substrate and the forming gasket substrate together, so that the interface coating tightly bonded between the wear-resistant corrosion-resistant coating and the forming mandrel substrate and the forming gasket substrate is not easy to fall off. More importantly, the wear-resistant corrosion-resistant coating is prepared by using nano-scale titanium nitride as a raw material and utilizing the nano effect of nano particles, so that the prepared wear-resistant corrosion-resistant coating has higher glossiness and lower friction coefficient, the friction force between a forming part of an aluminum pipe continuous extrusion die and aluminum liquid is greatly reduced, the aluminum liquid is not easy to adhere and accumulate on the forming part of the aluminum pipe continuous extrusion die in the aluminum pipe production process, and the surface of the prepared aluminum pipe is ensured to be smooth and have no scratches.

Furthermore, the wear-resistant corrosion-resistant coating takes nano titanium nitride as a raw material, so that the hardness of the prepared wear-resistant corrosion-resistant coating is higher than that of the forming core rod substrate and the forming gasket substrate, and simultaneously, the wear-resistant corrosion-resistant coating has high oxidation resistance, better adhesion resistance, higher wear resistance and better crater wear resistance, so that the size stability, the high-temperature corrosion resistance and the high-temperature wear resistance of a forming part in the aluminum pipe continuous extrusion die are obviously improved, and the service life of the aluminum pipe continuous extrusion die is obviously prolonged.

Example 2

The present embodiment provides a continuous extrusion die for aluminum pipes, which has a structure different from that of embodiment 1 in that:

the thickness of the wear-resistant corrosion-resistant coating is 10 micrometers, and the thickness of the forming gasket 8 is 3 millimeters; the wear-resistant corrosion-resistant coating is a nano titanium carbide layer; the forming core rod substrate and the forming gasket substrate are processed by hard alloy materials comprising the following components in percentage by mass: 85% of WC, 5% of TiC and 10% of Co.

Example 3

This embodiment provides a continuous extrusion die for aluminum pipes, which has substantially the same structure as that of embodiment 1, except that:

the thickness of the wear-resistant corrosion-resistant coating is 8 micrometers, the thickness of the forming gasket is 8 millimeters, and the wear-resistant corrosion-resistant coating is a nano titanium carbonitride layer; the forming core rod substrate and the forming gasket substrate are processed by hard alloy materials comprising the following components in percentage by mass: 82% of WC, 6% of TiC, 8% of Co and 4% of TaC.

Example 4

This example provides a continuous extrusion die for aluminum pipes, which has substantially the same structure as the steps in example 1, except that: the cross section of the shaping inner core 31 is a polygon, and the cross section of the female die forming through hole 6 is a polygon matched with the shaping inner core 31. The forming core rod substrate and the forming gasket substrate are made of titanium carbide niobium molybdenum alloy.

Example 5

The present embodiment provides an aluminum pipe continuous extrusion die, and as shown in fig. 9 and 10, the present embodiment is different from the above embodiments in that: the shaping inner core 31 is in a toothed polygon shape, and the cross section of the female die forming through hole 6 is a long round hole matched with the shaping inner core 31. In this embodiment, the number of the diversion trenches 2 is two, and the shaped inner core 31 substrate and the shaped gasket substrate are made of titanium-niobium-molybdenum nitride alloy.

Comparative example 1

This comparative example provides an aluminum pipe continuous extrusion die having substantially the same procedure as in example 1 except that: the forming mandrel base material of the aluminum pipe continuous extrusion die provided by the comparative example was a group YG8 cemented carbide, and no coating was deposited on the surface of the mandrel, and the group YG8 cemented carbide composition included 92 mass% of WC and 8 mass% of Co.

Comparative example 2

The present comparative example provides a type YG6 cemented carbide as a base material of a molding mandrel used in a shaping die member for aluminum pipe extrusion molding, and a titanium nitride coating layer having a thickness of 5 μm was deposited on the surface of the molding mandrel base by a chemical deposition method. The YG6 type hard alloy composition contained 94% WC by mass and 6% Co by mass.

Performance testing

Respectively detecting and counting the Rockwell hardness, the interlayer bonding force and the Rockwell hardness at 500 ℃ of the aluminum pipe continuous extrusion dies provided by the embodiments 1 to 5 and the comparative examples 1 to 2, simultaneously respectively designing the size of a forming part of the aluminum pipe continuous extrusion die to be capable of simultaneously producing thin-wall aluminum pipes with the specifications of 7.5mm in outer diameter and 0.7mm in pipe wall thickness, respectively producing the thin-wall aluminum pipes with the specifications by using the aluminum pipe continuous extrusion dies, and counting the ton number of aluminum liquid which can be processed when the dies are scrapped; the above-mentioned test and statistical results are shown in table 1.

As can be seen from the table, the aluminum pipe continuous extrusion dies provided in examples 1 to 5 all have higher Vickers hardness and stronger interlayer bonding force than those of comparative examples 1 to 2. Therefore, the titanium element contained in the wear-resistant corrosion-resistant coating and the titanium element contained in the hard alloy can obviously improve the binding force between the wear-resistant corrosion-resistant coating and the forming core rod substrate and between the wear-resistant corrosion-resistant coating and the forming gasket substrate. Meanwhile, the wear-resistant corrosion-resistant coating is deposited on the forming core rod substrate and the forming gasket substrate, so that the aluminum pipe continuous extrusion die is excellent in wear resistance and high in red hardness, and the aluminum pipe continuous extrusion die is not easy to adhere to aluminum liquid, and the service life of the aluminum pipe continuous extrusion die can be prolonged.

Performance test of aluminum pipe continuous extrusion dies provided in Table 1, examples 1 to 5 and comparative examples 1 to 2

	Rockwell hardness	Interlayer bonding force	Rockwell hardness at a temperature of 500 DEG C	Tonnage of aluminum liquid processed
					Example 1	94	70 Mpa	90	40 ton of
Example 2	93	72 Mpa	89	42 ton of
					Example 3	90	71 Mpa	87	45 ton of
Example 4	91	70 Mpa	90	41 ton of
					Example 5	92	70 Mpa	90	40 ton of
Comparative example 1	82	Is free of	71	8 ton of
					Comparative example 2	86	62 Mpa	75	17 ton of

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention and not to limit it; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the present invention, it is intended to cover all aspects of the invention as defined by the appended claims.

Claims

1. A continuous extrusion die for aluminum pipes comprises a male die and a female die and is characterized in that a forming core rod is detachably arranged on the male die, the female die comprises a female die base body, a forming gasket and a female die forming through hole, wherein an inverted frustum-shaped female die forming cavity is formed in the female die base body, the forming gasket is arranged at the center of the inverted frustum-shaped female die forming cavity, the female die forming through hole penetrates through the female die base body and the forming gasket,

the surface roughness Ra values of the forming core rod matrix and the forming gasket matrix are both 0.01-0.1; the thickness of the wear-resistant corrosion-resistant coating is 5-10 microns; the thickness of the formed gasket is 3-8 mm;

the male die comprises a male die base body, a male die forming boss and at least two shunting grooves penetrating through the male die forming boss and the male die base body, the male die base body and the male die forming boss are integrally arranged, an assembly blind hole is formed in the outer end face of the male die forming boss, the male die forming boss is matched with the inverted frustum-shaped female die forming cavity to form an aluminum liquid circulation channel,

the forming core rod base body comprises an installation handle and a forming inner core matched with the female die forming through hole, the installation handle and the forming inner core are integrally arranged, the installation handle is arranged in the assembling blind hole, and the installation handle is in interference fit with the assembling blind hole;

the tungsten-titanium alloy also comprises NbC or TaC, and the tungsten-titanium alloy matrix containing the NbC or TaC comprises 82-85% by mass of WC, 6% by mass of TiC, 6-8% by mass of Co and the balance of NbC or TaC;

the cross section of the shaping inner core is circular, triangular or polygonal; the cross section of the female die forming through hole is circular, triangular or polygonal and is matched with the shaping inner core.

2. The aluminum pipe continuous extrusion die as recited in claim 1, wherein the forming mandrel is produced by:

3. The aluminum pipe continuous extrusion die as recited in claim 1, wherein the forming shim is produced by:

4. The continuous extrusion die for the aluminum pipe as recited in claim 1, wherein the forming end of the sizing inner core is in a long-strip-shaped toothed structure, and the cross section of the female die forming through hole is an oblong hole matched with the sizing inner core.