CN111283174A - Hollow metal ball composite material with pore gradient - Google Patents
Hollow metal ball composite material with pore gradient Download PDFInfo
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- CN111283174A CN111283174A CN202010232996.4A CN202010232996A CN111283174A CN 111283174 A CN111283174 A CN 111283174A CN 202010232996 A CN202010232996 A CN 202010232996A CN 111283174 A CN111283174 A CN 111283174A
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- metal
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D19/00—Casting in, on, or around objects which form part of the product
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
- B22D17/02—Hot chamber machines, i.e. with heated press chamber in which metal is melted
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/08—Alloys with open or closed pores
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/08—Alloys with open or closed pores
- C22C1/081—Casting porous metals into porous preform skeleton without foaming
Abstract
The invention relates to a hollow metal ball composite material with a pore gradient, which is characterized in that the diameter of a hollow metal ball with the diameter range of 1-10mm is screened by taking 1mm as a unit, a metal hollow ball structure is formed by stacking a small-diameter hollow metal ball below and a large-diameter hollow metal ball above a mold, a metal wire mesh is placed on the metal hollow ball structure, a metal matrix ingot and a pressure head are placed on the metal wire mesh, the mold is placed in a heating device and heated to be above the melting point of matrix alloy, and a certain pressure is applied to the pressure head, so that metal melt fully flows into the hollow ball structure to be well combined with the hollow metal ball, and the hollow metal ball composite material with the pore gradient is obtained. The invention realizes the gradient distribution of the pores in the hollow metal ball composite material by arranging and designing the hollow metal balls, thereby improving the performance of the composite material.
Description
Technical Field
The invention relates to a metal hollow sphere composite material, in particular to a metal hollow sphere composite material with a pore gradient, and belongs to the technical field of design and preparation of multifunctional gradient composite materials.
Background
The metal foam material has a special hole structure, so that the metal foam material has a series of excellent characteristics of light weight, high strength, impact resistance, vibration reduction and isolation, heat insulation, radiation shielding and the like, and is widely applied to relevant fields of aerospace, ship and vehicle manufacturing, nuclear industry and the like. Most of the existing metal foams are formed by mixing open cells and closed cells, and the size and distribution uniformity of pores are difficult to control, so that the performance of the metal foam has larger uncertainty. The prior research shows that the performance of the metal foam material depends on the porous structure in the material. The metal hollow sphere composite material can effectively solve the series limitations in the traditional metal foam material, and is mainly characterized in that the metal hollow sphere composite material is a special metal foam formed by combining a millimeter-scale metal hollow sphere and a dissimilar metal matrix through casting, powder metallurgy and other methods, and in the preparation process, the size of the metal hollow sphere can be designed through the arrangement mode of the metal hollow sphere in the composite material, and the size of the metal hollow sphere is changed, so that the size and distribution of pores in the metal hollow sphere composite material can be controlled and designed, and further the directionality design of the performance of the multifunctional metal hollow sphere composite material is realized. Compared with the traditional metal foam, the material has more excellent mechanical properties and physical properties, such as good energy absorption property, heat insulation, shielding, sound absorption, damping and the like.
Disclosure of Invention
The invention provides a metal hollow sphere composite material with a pore gradient for improving the performance of the composite material.
The invention is realized by the following steps:
the hollow metal ball composite material with the pore gradient is prepared by taking hollow metal balls with two different diameter ranges and a metal substrate as raw materials, orderly arranging the hollow metal balls in a mould and performing a pressure casting method.
The diameter range of the metal hollow ball is 1-10 mm;
the metal hollow balls are classified by taking 1mm as a gradient, and the diameter of the large-diameter metal hollow ball is larger than two gradients of the small-diameter metal hollow ball;
the metal hollow ball is made of stainless steel or titanium alloy;
the metal matrix is made of aluminum alloy or steel; the melting point of the base metal material is lower than that of the metal hollow ball material;
the metal hollow balls are orderly arranged in the die, and the large-diameter metal hollow balls are stacked on the small-diameter metal hollow balls;
the pressure casting method specifically comprises the following steps: placing a metal matrix cast ingot on the orderly arranged metal hollow spheres, and placing a pressure head on the metal matrix cast ingot; putting the mould into a heating device, heating to a certain temperature above the melting point of the base alloy and below the melting point of the metal hollow sphere, and preserving heat; when the temperature is raised to be higher than the melting point, continuously applying certain pressure to the pressure head; with the continuous increase of the pressure, the residual metal melt is extruded out from a gap between the pressure head and the die and stops when the pressure cannot be continuously applied downwards; taking the mold out of the heating equipment, cooling and standing; after the temperature is reduced to the room temperature, taking out the composite material;
the heating device is a well-type heating furnace.
The invention has the beneficial effects that:
the invention carries out structural pre-design on the metal hollow spheres with different size ranges, realizes the forming of the composite material by methods such as pressure casting and the like, and forms the metal hollow sphere composite material with pore gradient, thereby improving the performance of the composite material.
In the metal hollow sphere composite material, the metal hollow sphere is used as a pore-forming agent, and the size of the metal hollow sphere directly influences the size of pores in the composite material. Two kinds of hollow metal balls with different diameter ranges are selected as pore forming agents, and the hollow metal ball composite material with two pore sizes can be obtained.
The metal hollow spheres are arranged along the casting (gravity) direction according to the sequence of the small spheres at the lower part and the large spheres at the upper part, so that the metal hollow sphere structure with the small-diameter metal hollow spheres at the lower part of the mold and the large-diameter metal hollow spheres at the upper part of the mold is obtained. The arrangement mode can form two pores in the matrix, the positions of the hollow spheres can be maintained, and the degree of disorder is low; and the structure can be maintained in the casting process due to the arrangement along the casting (gravity) direction, so that the metal hollow sphere composite material with the pore gradient is obtained.
The invention selects the pressure casting method to ensure that the matrix metal melt fully infiltrates and flows into the metal hollow sphere structure, which is beneficial to keeping good combination of the metal hollow sphere and the matrix in the composite material finished product and reducing defects.
Drawings
Fig. 1 is a schematic view of a metal hollow sphere composite material with a pore gradient and a preparation method thereof, wherein: 1 is a ram; 2 is a mold; 3 is a metal matrix (ingot); 4 is a wire mesh; 5 is a large-diameter metal hollow sphere; and 6 is a small-diameter metal hollow sphere.
Fig. 2 is a composite material of hollow metal spheres with gradient pores obtained in example 1 of the present invention.
Detailed Description
The invention is described in detail below with reference to the accompanying drawings and specific embodiments.
The hollow metal ball composite material with the pore gradient is prepared by taking hollow metal balls with two different diameter ranges and a metal substrate as raw materials, orderly arranging the hollow metal balls in a die and adopting a pressure casting method.
The metal hollow ball has the following characteristics:
(1) the diameter range of the metal hollow ball is 1-10 mm;
(2) the metal hollow spheres are classified by taking 1mm as a gradient. The diameter of the large-diameter hollow metal ball needs to be larger than that of the small-diameter hollow metal ball by two gradients;
(3) the hollow metal balls are made of metals such as stainless steel, titanium alloy and the like.
The metal matrix has the following characteristics:
(1) common metals such as aluminum alloys and steel;
(2) the melting point of the base metal material is lower than that of the hollow metal ball material.
The small-diameter hollow metal balls are positioned at the lower part of the die, and the large-diameter hollow metal balls are stacked on the small-diameter hollow metal balls and positioned at the upper part of the die.
The preparation method comprises the following steps:
placing a metal matrix cast ingot on the orderly arranged metal hollow spheres, and placing a pressure head on the metal matrix cast ingot; putting the mould into a heating device, heating to a certain temperature above the melting point of the base alloy and below the melting point of the metal hollow sphere, and preserving heat; when the temperature is raised to be higher than the melting point, continuously applying certain pressure to the pressure head; with the continuous increase of the pressure, the residual metal melt is extruded out from a gap between the pressure head and the die and stops when the pressure cannot be continuously applied downwards; taking the mold out of the heating equipment, cooling and standing; and after the temperature is reduced to the room temperature, taking out the composite material.
The heating equipment is a heating device such as a well-type heating furnace and the like.
Example 1
Step one, filling raw materials. Respectively ultrasonically cleaning 300 stainless steel hollow spheres with the diameter range of 1-2mm and 200 stainless steel hollow spheres with the diameter range of 5-6mm for 10min by using alcohol, and removing surface stains. Filling a 316L stainless steel hollow ball with the diameter of 1-2mm into the bottom of a cylindrical graphite mould, placing the 316L stainless steel hollow ball with the diameter of 5-6mm on the cylindrical graphite mould, fixing a stainless steel wire mesh on the top of the hollow ball, and placing an A356 alloy cast ingot on the upper part of the stainless steel wire mesh. And placing a graphite pressure head on the alloy cast ingot.
And step two, preparing the metal hollow sphere composite material with the gradient structure. And placing the mould filled with the raw materials into a pit furnace for heating. The temperature is raised to 700 ℃ and pressure is applied to the pressure head, so that the pressure head moves downwards until the downward movement cannot be continued. After keeping the temperature for 45 minutes in this state, the mold was taken out. The air was cooled to room temperature and the sample was taken out.
Example 2
Step one, filling raw materials. Respectively ultrasonically cleaning 300 stainless steel hollow spheres with the diameter of 1-2mm and 100 stainless steel hollow spheres with the diameter of 8-9mm for 10min by using alcohol, and removing surface stains. Filling a 316L stainless steel hollow ball with the diameter of 1-2mm into the bottom of a cylindrical graphite mould, placing the 316L stainless steel hollow ball with the diameter of 8-9mm on the cylindrical graphite mould, fixing a stainless steel wire mesh on the upper part of the hollow ball, and placing a 7075 alloy ingot on the upper part of the stainless steel wire mesh. And placing a graphite pressure head on the alloy cast ingot.
And step two, preparing the metal hollow sphere composite material with the gradient structure. And placing the mould filled with the raw materials into a pit furnace for heating. The temperature is raised to 700 ℃ and pressure is applied to the pressure head, so that the pressure head moves downwards until the downward movement cannot be continued. After keeping the temperature for 45 minutes in this state, the mold was taken out. The air was cooled to room temperature and the sample was taken out.
Example 3
Step one, filling raw materials. Respectively cleaning 200 stainless steel hollow spheres with diameters of 4-5mm and 100 stainless steel hollow spheres with diameters of 9-10mm with alcohol under ultrasonic for 10min to remove surface stains. Filling a hollow 304 stainless steel ball of 4-5mm into the bottom of a cylindrical graphite mould, placing the hollow 304 stainless steel ball of 9-10mm on the hollow 304 stainless steel ball, fixing a stainless steel wire mesh on the hollow 304 stainless steel ball, and placing an 1100 pure aluminum ingot on the upper part of the stainless steel wire mesh. And placing a graphite pressure head on the alloy cast ingot.
And step two, preparing the metal hollow sphere composite material with the gradient structure. And placing the mould filled with the raw materials into a pit furnace for heating. The temperature is raised to 720 ℃ and pressure is applied to the pressure head, so that the pressure head moves downwards until the downward movement cannot be continued. After keeping the temperature for 30 minutes in this state, the mold was taken out. The air was cooled to room temperature and the sample was taken out.
Example 4
Step one, filling raw materials. Respectively cleaning 100 TC4 titanium alloy hollow spheres with the diameter range of 1-2mm and 50 TC4 titanium alloy hollow spheres with the diameter range of 4-5mm for 10min by using alcohol through ultrasonic waves, and removing surface stains. Filling 1-2mm TC4 titanium alloy hollow spheres into the bottom of a cylindrical graphite mold, placing 4-5mm TC4 titanium alloy hollow spheres on the hollow spheres, fixing a stainless steel wire mesh on the hollow spheres, and placing 1100 pure aluminum cast ingots on the upper part of the stainless steel wire mesh. And placing a graphite pressure head on the alloy cast ingot.
And step two, preparing the metal hollow sphere composite material with the gradient structure. And placing the mould filled with the raw materials into a pit furnace for heating. The die was heated to 720 c and pressure was applied to the ram to move the ram down until no further downward movement was possible. After keeping the temperature for 10 minutes in this state, the mold was taken out. The air was cooled to room temperature and the sample was taken out.
In summary, the following steps: the invention provides a hollow metal sphere composite material with a pore gradient. The diameter of the metal hollow sphere with the diameter range of 1-10mm is sieved by taking 1mm as a unit. The metal hollow ball structure is formed by stacking the small-diameter metal hollow ball below and the large-diameter metal hollow ball above the die. A wire mesh is placed on the casting mold, and a metal matrix ingot and a pressure head are placed on the wire mesh. And (3) putting the die into a heating device, heating to a temperature above the melting point of the matrix alloy, and applying a certain pressure to the pressure head so that the metal melt fully flows into the hollow sphere structure to form good combination with the metal hollow sphere. The metal hollow sphere composite material with the pore gradient is prepared. The metal hollow spheres are arranged and designed to realize the gradient distribution of pores in the metal hollow sphere composite material, so that the performance of the composite material is improved.
Claims (8)
1. A hollow metal ball composite material with a pore gradient is characterized in that: the hollow metal ball composite material with the pore gradient is obtained by taking hollow metal balls with two different diameter ranges and a metal matrix as raw materials, orderly arranging the hollow metal balls in a mould and performing a pressure casting method.
2. The hollow metal sphere composite material with a pore gradient of claim 1, wherein: the diameter range of the metal hollow ball is 1-10 mm.
3. The hollow metal sphere composite material with a pore gradient of claim 1 or 2, wherein: the metal hollow balls are classified by taking 1mm as a gradient, and the diameter of the large-diameter metal hollow ball is larger than two gradients of the small-diameter metal hollow ball.
4. The hollow metal sphere composite material with a pore gradient of claim 1 or 2, wherein: the metal hollow ball is made of stainless steel or titanium alloy.
5. The hollow metal sphere composite material with a pore gradient of claim 1, wherein: the metal matrix is made of aluminum alloy or steel; the melting point of the base metal material is lower than that of the hollow metal ball material.
6. The hollow metal sphere composite material with a pore gradient of claim 1, wherein: the metal hollow balls are orderly arranged in the die, and the large-diameter metal hollow balls are stacked on the small-diameter metal hollow balls.
7. The hollow metal sphere composite material with a pore gradient of claim 1, wherein: the pressure casting method specifically comprises the following steps: placing a metal matrix cast ingot on the orderly arranged metal hollow spheres, and placing a pressure head on the metal matrix cast ingot; putting the mould into a heating device, heating to a certain temperature above the melting point of the base alloy and below the melting point of the metal hollow sphere, and preserving heat; when the temperature is raised to be higher than the melting point, continuously applying certain pressure to the pressure head; with the continuous increase of the pressure, the residual metal melt is extruded out from a gap between the pressure head and the die and stops when the pressure cannot be continuously applied downwards; taking the mold out of the heating equipment, cooling and standing; and after the temperature is reduced to the room temperature, taking out the composite material.
8. The hollow metal sphere composite material with a pore gradient of claim 7, wherein: the heating device is a well-type heating furnace.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202010232996.4A CN111283174A (en) | 2020-03-28 | 2020-03-28 | Hollow metal ball composite material with pore gradient |
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| CN202010232996.4A CN111283174A (en) | 2020-03-28 | 2020-03-28 | Hollow metal ball composite material with pore gradient |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113560543A (en) * | 2021-07-27 | 2021-10-29 | 东北大学 | Preparation method of aluminum-based composite porous material with gradient structure and controllable deformation |
| CN114012070A (en) * | 2021-10-28 | 2022-02-08 | 苏州市祥冠合金研究院有限公司 | Preparation method of hollow ceramic ball reinforced metal matrix composite material and composite material |
| CN114231778A (en) * | 2021-12-20 | 2022-03-25 | 哈尔滨工业大学 | Preparation method of density gradient hollow sphere reinforced aluminum-based porous composite material |
| CN114505465A (en) * | 2020-11-16 | 2022-05-17 | 鞍钢股份有限公司 | Preparation method of composite foam steel |
| CN114951552A (en) * | 2022-05-06 | 2022-08-30 | 大连理工大学 | Preparation method and mold of aluminum-based steel hollow sphere reinforced composite material |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114505465A (en) * | 2020-11-16 | 2022-05-17 | 鞍钢股份有限公司 | Preparation method of composite foam steel |
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| CN114231778A (en) * | 2021-12-20 | 2022-03-25 | 哈尔滨工业大学 | Preparation method of density gradient hollow sphere reinforced aluminum-based porous composite material |
| CN114951552A (en) * | 2022-05-06 | 2022-08-30 | 大连理工大学 | Preparation method and mold of aluminum-based steel hollow sphere reinforced composite material |
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