CN117358884A - Metal casting mold and molding process for casting large-size zinc alloy plate by using metal casting mold - Google Patents
Metal casting mold and molding process for casting large-size zinc alloy plate by using metal casting mold Download PDFInfo
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- CN117358884A CN117358884A CN202311113164.0A CN202311113164A CN117358884A CN 117358884 A CN117358884 A CN 117358884A CN 202311113164 A CN202311113164 A CN 202311113164A CN 117358884 A CN117358884 A CN 117358884A
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- casting
- metal
- pouring gate
- melt
- mold
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- 238000005266 casting Methods 0.000 title claims abstract description 48
- 238000005058 metal casting Methods 0.000 title claims abstract description 16
- 238000000465 moulding Methods 0.000 title claims abstract description 9
- 229910001297 Zn alloy Inorganic materials 0.000 title claims description 18
- 238000000034 method Methods 0.000 title claims description 11
- 230000008569 process Effects 0.000 title claims description 10
- 229910052751 metal Inorganic materials 0.000 claims abstract description 23
- 239000002184 metal Substances 0.000 claims abstract description 23
- 239000007788 liquid Substances 0.000 claims abstract description 20
- 239000004576 sand Substances 0.000 claims abstract description 14
- 239000002966 varnish Substances 0.000 claims abstract description 12
- 239000000155 melt Substances 0.000 claims description 26
- 239000002893 slag Substances 0.000 claims description 12
- 229910052782 aluminium Inorganic materials 0.000 claims description 11
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 11
- 238000003756 stirring Methods 0.000 claims description 10
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 7
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 7
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 7
- 229910052802 copper Inorganic materials 0.000 claims description 7
- 239000010949 copper Substances 0.000 claims description 7
- 229910052749 magnesium Inorganic materials 0.000 claims description 7
- 239000011777 magnesium Substances 0.000 claims description 7
- 239000011248 coating agent Substances 0.000 claims description 5
- 238000000576 coating method Methods 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 5
- 238000002844 melting Methods 0.000 claims description 5
- 230000008018 melting Effects 0.000 claims description 5
- 229910052725 zinc Inorganic materials 0.000 claims description 5
- 239000011701 zinc Substances 0.000 claims description 5
- 238000001816 cooling Methods 0.000 claims description 4
- 238000004321 preservation Methods 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 238000003723 Smelting Methods 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 claims description 2
- 238000010907 mechanical stirring Methods 0.000 claims description 2
- 238000005507 spraying Methods 0.000 claims description 2
- 238000007605 air drying Methods 0.000 claims 1
- 230000007547 defect Effects 0.000 abstract description 7
- 239000003110 molding sand Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 3
- 238000007711 solidification Methods 0.000 description 3
- 230000008023 solidification Effects 0.000 description 3
- 238000007664 blowing Methods 0.000 description 2
- 230000001680 brushing effect Effects 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 239000003365 glass fiber Substances 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 238000009423 ventilation Methods 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000002860 competitive effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000003892 spreading Methods 0.000 description 1
- 230000007480 spreading Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/06—Permanent moulds for shaped castings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/08—Features with respect to supply of molten metal, e.g. ingates, circular gates, skim gates
- B22C9/082—Sprues, pouring cups
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/08—Features with respect to supply of molten metal, e.g. ingates, circular gates, skim gates
- B22C9/086—Filters
-
- 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
- C22C1/02—Making non-ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C18/00—Alloys based on zinc
- C22C18/04—Alloys based on zinc with aluminium as the next major constituent
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Molds, Cores, And Manufacturing Methods Thereof (AREA)
Abstract
The invention discloses a metal casting mold, which comprises an upper cover plate, a middle frame and a lower bottom plate which are arranged from top to bottom, wherein the upper cover plate is formed by splicing a plurality of cover plates; the pouring gate is of a strip-shaped opening structure, the bottom of the pouring gate is provided with at least two liquid leakage ports, and the liquid leakage ports are communicated with the inner pouring gate on the middle type frame; during casting, a layer of metal varnish is coated on the surface of the lower bottom plate, a layer of sand for 30-50 mesh molding or core making is coated, and the whole mold is placed on an inclined plane with an inclination angle of 5-10 degrees, so that casting defects of the cast plate are reduced, and the yield and the component quality are improved.
Description
Technical Field
The invention relates to the field of forming processes of large-size zinc alloy plates, in particular to a metal casting mold and a forming process for casting the large-size zinc alloy plates by using the mold.
Background
The guide rail plate is a common structural functional component on mechanical equipment and plays a good guiding role. As the guide rail plate, good wear resistance is required, and the commonly used guide rail plate material comprises copper alloy, aluminum alloy, steel and the like, and zinc alloy is widely applied to the market due to the excellent forming process characteristics and competitive price. Besides good processing and forming properties, the zinc alloy also has good wear resistance and bearing capacity, and is an ideal guide rail plate material under the condition of large load.
Zinc alloys with high aluminum content (e.g., ZA-27) have higher strength and hardness than zinc alloys with low aluminum content (e.g., ZA-3), and are excellent materials for making rail plates. The zinc alloy with high aluminum content is more prone to casting defects such as shrinkage cavities, shrinkage porosity, air holes, pinholes and the like generated by improper control of a casting process in the casting process, so that the mechanical properties and the service life of a final component are affected.
Zinc alloys are typically cast from metal or sand and then machined into rail members. The casting and processing technology of the small-size zinc alloy guide rail plate is easy to control, and the large-size and large-thickness zinc alloy plate has more technical problems in the casting process, so that the blank is unstable in quality and high in rejection rate. At present, manufacturers capable of casting large-size zinc alloy plates with the size of 1000 x 600 x 60mm are few, and the casting process is relatively backward and lacks scientificity and advancement. The traditional mode of casting such plates is that the tops of metal double persons are obliquely cast, and although the mode can produce such plates, large air holes are formed on the lower surface of most casting blanks due to unsmooth exhaust, slag holes and air holes are formed on the upper surface, and deeper air holes and shrinkage cavity shrinkage porosity defects are formed in the central final solidification area.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a metal casting mould and a forming process for casting a zinc alloy plate with high aluminum content by using the mould, so as to reduce casting defects of the cast plate, improve the yield and the component quality and solve the defects caused by the prior art.
In order to achieve the above object, the present invention provides the following technical solutions: the metal casting mold comprises an upper cover plate, a middle frame and a lower bottom plate which are arranged from top to bottom, wherein the upper cover plate is formed by splicing a plurality of cover plates; the pouring gate is of a strip-shaped opening structure, at least two liquid leakage ports are arranged at the bottom of the pouring gate, and the liquid leakage ports are communicated with the inner pouring gate on the middle type frame.
Preferably, a filter screen is arranged at the liquid leakage port.
A molding process for casting a large-size zinc alloy plate by using the metal casting mold comprises the following steps of
1) Putting the weighed zinc ingot, aluminum ingot, copper ingot and magnesium ingot into a resistance furnace, heating and melting, and preserving heat;
2) Assembling a metal casting mold, coating a layer of metal varnish on the surface of a lower base plate, coating a layer of sand for 30-50 mesh molding or core making, and placing the whole mold on an inclined plane with an inclination angle of 5-10 degrees;
3) Pouring the melt into a casting ladle after the heat preservation time of the melt is up, adding the slag remover into the casting ladle again, fully stirring to fully float inclusions, and fishing out slag;
4) Pouring the melt in the casting ladle slowly and uniformly into the middle of the pouring gate, enabling the melt to enter the inner pouring gate from the liquid leakage port, gradually filling the whole cavity from the bottom of the cavity, sequentially solidifying the melt in the cavity, and opening the die after 5-10 minutes to obtain a casting with good quality;
5) And (5) putting the die into a water tank for cooling, and taking out the casting piece for casting of the next round.
Preferably, in the step 1), firstly, the weighed zinc, aluminum and copper ingots are put into a resistance furnace for heating and melting, the melting temperature is 750 ℃, the mechanical stirring is carried out for 30 minutes, the weighed magnesium ingots are added, the slag remover is added, the stirring is continued for 15 minutes, and the surface scum is fished out after the reaction is finished; the melt was incubated at 700 degrees celsius for 1 hour.
Preferably, in the step 2), the thickness of the sand layer on the lower bottom plate is controlled to be between 0.5 and 1mm, and the sand layer is aired for 30 minutes after sanding so that the varnish forms certain bonding strength.
The beneficial effects of adopting above technical scheme are: according to the metal casting mold, the lower base plate adopts the sand-coated metal mold which is equivalent to the sand-coated metal mold, so that the problem of ventilation of the lower metal mold is solved. The upper cover plate adopts a combined cover plate to solve the problem of air permeability of the metal mold; the forming runner is adopted to solve the problem that the original double casting is changed into single casting, so that the labor intensity of staff is reduced, and meanwhile, the double runner bottom casting is arranged to solve the problem of sequential solidification.
Drawings
FIG. 1 is a metal mold assembly;
FIG. 2 is a schematic view of the structure of an intermediate frame;
FIG. 3 is a schematic structural view of a gate;
wherein, 1-upper cover plate, 2-middle frame, 3-lower bottom plate, 4-gate, 5-liquid leakage port, 6-filter screen.
Detailed Description
Preferred embodiments of the present invention are described in detail below.
According to the figures 1-3, a metal casting mould comprises an upper cover plate 1, a middle mold frame 2 and a lower bottom plate 3 which are arranged from top to bottom, and is characterized in that the upper cover plate 1 is formed by splicing a plurality of cover plates; the pouring gate 4 is of a strip-shaped opening structure, the bottom of the pouring gate 4 is provided with at least two liquid leakage ports 5, and the liquid leakage ports 5 are communicated with the inner pouring gate on the middle mold frame 2; the liquid leakage port 5 is provided with a filter screen 5.
The lower type bottom plate needs to be pretreated, and the treatment method comprises the following steps: firstly, cleaning the surface of a lower base plate, then uniformly coating a layer of varnish, and uniformly scattering molding sand on the varnish to form a sand layer with a certain thickness. The treatment can effectively solve the problem of poor ventilation of the metal mold, effectively exhaust the gas at the bottom in the casting process, and reduce the air hole defect on the lower surface of the blank.
The upper cover plate adopts a mode of splicing a plurality of cover plates, the splice joints are in natural contact without welding, the splice joints are used as exhaust holes, so that the gas on the upper surface of a casting can be effectively exhausted, and the number of air holes on the upper surface is reduced.
The pouring gate part is designed into a strip-shaped opening type, two liquid leakage openings are formed in the bottom, molten metal in the pouring ladle is poured in from the middle of the strip, and the molten metal enters the inner pouring gate from the liquid leakage openings at two sides and finally enters the cavity. The liquid leakage port is provided with a filter screen for further purifying impurities in the melt.
The whole device adopts inclined pouring, namely the part of the pouring gate is lifted to a certain height, and the lower template forms a certain angle with the horizontal plane, so that the purposes of exhausting and sequential solidification are achieved, and the defects in castings are reduced.
The specific casting process is as follows:
(1) And (3) putting the weighed zinc, aluminum and copper ingots into a resistance furnace, heating and melting the ingots, mechanically stirring the ingots for 30 minutes at the smelting temperature of 750 ℃, adding the weighed magnesium ingots, adding a slag remover, continuously stirring the ingots for 15 minutes, and fishing out surface scum after the reaction is finished. The melt was kept at 700 degrees celsius for an additional 1 hour.
(2) The metal mold is pretreated and assembled during the heat preservation of the melt. Firstly, placing a lower base plate on an inclined plane which is arranged in advance, wherein the inclination angle is 5-10 degrees, removing molding sand, metal scraps and the like remained in the last casting of the surface, and blowing the surface by high-pressure gas. Brushing or spraying a varnish layer on the surface of the lower base plate by using a brush or a sprayer, wherein the varnish must completely cover the metal type surface.
The molding sand of 30 to 50 mesh was lightly sprinkled on the surface of the lower base plate with a 400X 400mm size screen to bond it with the varnish. The thickness of the sand layer is controlled between 0.5 mm and 1mm, so that the lower-layer gas can be smoothly discharged. And airing for 30 minutes after sanding is finished, so that the varnish forms certain bonding strength after the sand layer.
Placing the middle mold frame on the lower bottom plate, aligning the reserved bayonet slots, placing the upper cover plate on the middle mold frame in sequence, and aligning the bayonet slots in sequence; and placing the strip-shaped pouring gate on the middle frame, so that the two liquid leakage ports and the two ingate ports are respectively corresponding, and placing the glass fiber filter screen in the middle.
(3) After the heat preservation time of the melt is up, pouring the melt into a casting ladle, adding the slag remover into the casting ladle again, fully stirring to fully float the inclusions, and fishing out the slag. This operation is performed in order to produce a large amount of oxidizing slag due to the fact that the melt is in contact with a large amount of air during pouring, and further refining in the ladle can effectively remove the oxidizing slag, reducing the number of slag holes in the casting.
(4) Pouring the melt in the casting ladle slowly and uniformly into the middle of the pouring gate, enabling the melt to enter the inner pouring gate from the liquid leakage port, and gradually filling the whole cavity from the bottom of the cavity. And sequentially solidifying the melt in the cavity, and opening the die after 5-10 minutes to obtain the casting with good quality.
(5) And (5) putting the metal mold into a water tank for cooling, and taking out the metal mold for the next round of casting.
The specific implementation mode is as follows, (1) weighing 174Kg of zinc, 70Kg of aluminum, 6.25Kg of copper and 0.05Kg of magnesium, sequentially placing the aluminum, the copper and the zinc into a smelting furnace, heating to 7509 ℃, placing the molten metal into a mechanical stirrer for stirring after all the metal is melted, wherein the rotating speed of the stirrer is 90 revolutions per minute, and the stirring time is 20 minutes. The magnesium ingot is pressed into the melt to be dissolved by a cup cover, stirring is continued for 10 minutes, the slag removing agent is pressed into the bottom of the melt by the cup cover, and surface scum is fished after the reaction is finished. The temperature of the melt is regulated to 700 ℃, and the temperature is kept for 1 hour.
(2) And (3) hanging the cooled lower bottom plate to a designated position, wherein the included angle between the flat plate and the horizontal plane is 5 degrees, cleaning the surface by using a flat shovel, and blowing impurities and water by using high-pressure gas. Brushing a layer of varnish by a brush, uniformly spreading a layer of molding sand with 30-50 meshes by a sieve, wherein the layer thickness is 1mm. The mixture was left for 30 minutes.
(3) The middle mold frame is placed on the lower mold bottom plate, the upper mold cover plate is placed at the uppermost part, and the strip-shaped pouring gate is placed at the position of an included angle formed by the middle mold frame and the upper mold cover plate, so that the liquid leakage port and the inner pouring gate are aligned, and the glass fiber filter screen is placed between the inner pouring gate port and the liquid leakage port.
(4) 240Kg of melt was poured into a ladle, and the ladle was transferred to a gate of a metal mold. And slowly and continuously pouring the melt into a gate, and according to mass calculation, the melt just fills the cavity.
(5) Cooling for 5 minutes after the casting is solidified, opening the mould, and taking out the casting with good quality
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and improvements could be made by those skilled in the art without departing from the inventive concept, which falls within the scope of the present invention.
Claims (5)
1. The metal casting mold comprises an upper cover plate (1), an intermediate frame (2) and a lower base plate (3) which are arranged from top to bottom, and is characterized in that the upper cover plate (1) is formed by splicing a plurality of cover plates; the pouring gate structure is characterized by further comprising a pouring gate (4) which is arranged independently, wherein the pouring gate (4) is of a strip-shaped opening structure, at least two liquid leakage ports (5) are arranged at the bottom of the pouring gate, and the liquid leakage ports (5) are communicated with the inner pouring gate on the middle mold frame (2).
2. A metal casting mould according to claim 1, characterized in that the drain port (5) is provided with a filter screen (5).
3. A molding process for casting a large-size zinc alloy sheet using the metal mold according to claim 1 or 2, characterized by comprising the steps of
1) Putting the weighed zinc ingot, aluminum ingot, copper ingot and magnesium ingot into a resistance furnace, heating and melting, and preserving heat;
2) Assembling a metal casting mold, coating a layer of metal varnish on the surface of a lower base plate, coating a layer of sand for 30-50 mesh molding or core making, and placing the whole mold on an inclined plane with an inclination angle of 5-10 degrees;
3) Pouring the melt into a casting ladle after the heat preservation time of the melt is up, adding the slag remover into the casting ladle again, fully stirring to fully float inclusions, and fishing out surface scum;
4) Pouring the melt in the casting ladle slowly and uniformly into the middle of the pouring gate, enabling the melt to enter the inner pouring gate from the liquid leakage port, gradually filling the whole cavity from the bottom of the cavity, sequentially solidifying the melt in the cavity, and opening the die after 5-10 minutes to obtain a casting with good quality;
5) And (5) putting the die into a water tank for cooling, and taking out the casting piece for casting of the next round.
4. The molding process for casting large-size zinc alloy plates by using a metal casting mold according to claim 3, wherein in the step 1), firstly, weighed zinc, aluminum and copper ingots are put into a resistance furnace to be heated and melted, the smelting temperature is 750 ℃, the mechanical stirring is carried out for 30 minutes, the weighed magnesium ingots are added, the deslagging agent is added, the stirring is continued for 15 minutes, and the surface scum is fished out after the reaction is finished; the melt was incubated at 700 degrees celsius for 1 hour.
5. The molding process for casting large-size zinc alloy sheet using metal mold according to claim 4, wherein in the step 2), the thickness of the sand layer on the lower plate is controlled to be 0.5-1mm, and the varnish after sand layer is allowed to form a certain bonding strength after 30 minutes of air drying after sand spraying.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311113164.0A CN117358884A (en) | 2023-08-31 | 2023-08-31 | Metal casting mold and molding process for casting large-size zinc alloy plate by using metal casting mold |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311113164.0A CN117358884A (en) | 2023-08-31 | 2023-08-31 | Metal casting mold and molding process for casting large-size zinc alloy plate by using metal casting mold |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117358884A true CN117358884A (en) | 2024-01-09 |
Family
ID=89391804
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311113164.0A Pending CN117358884A (en) | 2023-08-31 | 2023-08-31 | Metal casting mold and molding process for casting large-size zinc alloy plate by using metal casting mold |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117358884A (en) |
-
2023
- 2023-08-31 CN CN202311113164.0A patent/CN117358884A/en active Pending
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