A die casting mold and a method for manufacturing the same

Abstract

The present invention discloses a die casting mold and a manufacturing method thereof, belonging to the field of die casting technology. The die casting mold fills silicate granule bulk material between the working layer and the insulation layer, and utilizes the low thermal conductivity of the bulk material and porosity to ensure the insulation performance of the mold and reduce heat loss. At the same time, it can also block molten steel when the working layer is damaged, avoid the impact of molten steel on the entire insulation layer, and prevent steel leakage. Thereby effectively improving the insulation performance and service life of the mold refractory material.

Description

Technical Field

[0001] The invention belongs to the technical field of die casting, and in particular relates to a die casting mold and a manufacturing method thereof. Background Art

[0002] At present, continuous casting cannot completely replace die casting production. The characteristics of some steel types cannot adapt to continuous casting, such as boiling steel and highly sensitive high-speed steel. It is difficult to ensure the quality of steel without die casting. Die casting steel has a long solidification time, which is conducive to the floating of large and medium-sized inclusions in steel and improves the purity of steel. Therefore, die casting is still widely used in the steel industry. However, the solidification quality of die casting steel has extremely high requirements on the high temperature resistance, thermal insulation, and thermal shock resistance of the refractory materials in the mold.

[0003] High-performance thermal insulation materials have the properties of high-efficiency thermal insulation, light weight, and high refractoriness. At present, the United States, Japan, Germany and other countries have developed high-performance alumina and zirconia fibers and their products that can be used for a long time at temperatures above 1500°C, and environmentally friendly and ecologically degradable fibers with an application temperature of more than 1260°C. However, due to the low strength of fiber materials and easy deformation under the impact of molten steel, their development in the steel industry is restricted. Summary of the invention

[0004] Purpose of the invention: In order to overcome the defects of the prior art, the present invention provides a die casting mold, which can ensure the sealing and heat insulation performance of the thermal insulation refractory material and prevent steel leakage.

[0005] Another object of the present invention is to provide a method for manufacturing the above-mentioned die casting mold.

[0006] Technical solution: The die casting mold described in the present invention includes a steel shell and a permanent layer, a thermal insulation layer and a working layer arranged in sequence from the steel shell inward, and is characterized in that it also includes a bulk material layer formed by filling with silicate particles, and the bulk material layer is arranged between the thermal insulation layer and the working layer.

[0007] Specifically, the particle size of the silicate particles in the bulk material layer is 0.02-3.35 mm.

[0008] Specifically, among the silicate particles in the bulk material layer, the content of particles with a particle size of 0-1 mm is more than 80%.

[0009] Specifically, the silicate particles in the bulk material layer have a composition by mass percentage of SiO2≥80%, and Fe2O3≤1.0%.

[0010] Specifically, the silicate particles of the bulk layer have a Mohs hardness of 5-7, a relative density of 2-3, and a melting point of 1700-1750°C.

[0011] Specifically, the permanent layer includes a nanofiber layer and an aluminum silicate fiber layer which are sequentially arranged inward from the steel shell.

[0012] Wherein, the nanofiber layer is made of a nanofiber board, and the volume density of the nanofiber board is ≤150Kg / m 3 , SiO2≥60% in the composition by mass percentage; the aluminum silicate fiber layer is made of an aluminum silicate fiberboard, and the volume density of the aluminum silicate fiberboard is 200-800Kg / m 3 In the composition by mass percentage, SiO2 ≥ 50%, Al2O3 ≥ 20%, and the heating line shrinkage at 1300°C for 24 hours is ≤ 6.0%.

[0013] Specifically, the insulation layer is composed of a polycrystalline fiberboard, and the volume density of the polycrystalline fiberboard is 200-600Kg / m 3 In the composition by mass percentage, SiO2≤30%, Al2O3≥60%, and the heating line shrinkage at 1300℃ for 24h is ≤1.0%.

[0014] Specifically, the working layer is composed of a silicon working lining, wherein the weight percentage composition of the silicon working lining is SiO2≥80%, Fe2O3<10%, and the heating line shrinkage at 1300°C for 24 hours is ≤2.0%.

[0015] Corresponding to the above-mentioned die casting mold, the technical solution adopted by the manufacturing method described in the present invention includes the following steps:

[0016] (1) Pasting the nanofiber board to the construction site of the steel shell, and fixing the aluminum silicate fiber board on the surface of the nanofiber board;

[0017] (2) Apply the adhesive evenly between the surfaces of each layer of the insulation layer, with the bonding area not less than 2 / 3; bond each adjacent polycrystalline fiberboard tightly and tie them firmly;

[0018] (3) Assemble the working layer lining and fix it on the inner side of the insulation layer, leaving a gap for the bulk material layer between the two; use dry masonry to build the working layer lining, keep the linings tight, and use fire clay to fill the gaps between the linings for leveling;

[0019] (4) Silicate particles are used to fill the space between the insulation layer and the working layer to form a bulk layer;

[0020] (5) Steel clips are used to fix the upper edge of the working layer lining.

[0021] Beneficial effects: The die casting mold fills the working layer and the insulation layer with silicate granules in bulk, and utilizes the low thermal conductivity of the bulk due to its material and porosity to ensure the insulation performance of the mold and reduce heat loss. At the same time, it can also block the molten steel when the working layer is damaged, avoiding the impact of the molten steel on the entire insulation layer and preventing steel leakage. This effectively improves the insulation performance and service life of the mold refractory material. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the distribution of each layer of the mold casting mold of the present invention;

[0023] Figure 2 yes Figure 1 A partial enlarged view of . DETAILED DESCRIPTION

[0024] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings.

[0025] like Figure 1-2 As shown, a die casting mold comprises a steel shell 1 and a permanent layer, a heat preservation layer 4, a bulk material layer 5, a working layer 6 and a gap filling part which are sequentially arranged inward from the steel shell 1.

[0026] The permanent layer is a nanofiber layer 2 formed by a nanofiber board with a thickness of 20 mm and an aluminum silicate fiber layer 3 formed by an aluminum silicate fiber board with a thickness of 50 mm. The performance indicators of the nanofiber board and the aluminum silicate fiber board are shown in Table 1-2.

[0027] Table 1 Performance indexes of nanofiber board

[0028] <![CDATA[Bulk density Kg / m 3 > <![CDATA[SiO2 / %]]> ≤150 ≥60

[0029] Table 2 Performance index of aluminum silicate fiberboard

[0030] <![CDATA[Bulk density Kg / m 3 > Heating line shrinkage [1300℃, 24h] % <![CDATA[Al2O3 / %]]> <![CDATA[SiO2 / %]]> 200-800 ≤6 ≥20 ≥50

[0031] The thermal insulation layer 4 is made of a polycrystalline fiberboard with a thickness of 60 mm, and its performance indicators are shown in Table 3.

[0032] Table 3 Performance indexes of polycrystalline fiberboard

[0033] <![CDATA[Bulk density Kg / m 3 > Heating line shrinkage % [1300℃, 24h] % <![CDATA[Al2O3 / %]]> <![CDATA[SiO2 / %]]> 200-600 ≤1.0 ≥60 ≤30

[0034] The working layer 6 adopts a 30 mm thick silicon working lining, and its performance indicators are shown in Table 4.

[0035] Table 4 Performance indexes of silicon working lining

[0036] Working temperature(℃) Heating line shrinkage % [1300℃, 24h] % <![CDATA[SiO2%]]> <![CDATA[Fe2O3% <!-- 2 -->]]> ≤1550 ≤2.0 ≥80 <10

[0037] The key point is that silicate particles are used to fill the space between the thermal insulation layer 4 and the working layer 6 to form a bulk material layer 5 with a thickness of 30 mm.

[0038] Furthermore, the gaps between each layer of the working lining plate and the surrounding areas of the mold are filled with silicate particles having the same performance to form gap filling parts.

[0039] Specifically, the silicate particles used have a particle size of 0.02-3.35 mm, the content of particles with a particle size of 0-1 mm is more than 80%, the mass percentage of the components is SiO2≥80%, Fe2O3≤1.0%, the Mohs hardness is 5-7, the relative density is 2-3, and the melting point is 1700-1750°C.

[0040] The low thermal conductivity of bulk material and porosity is used to ensure the thermal insulation performance of the mold and reduce heat loss. At the same time, it can also block the molten steel when the working layer is damaged, avoiding the impact of the molten steel on the entire insulation layer and preventing steel leakage. This effectively improves the thermal insulation performance and service life of the mold refractory material.

[0041] This embodiment also provides a method for manufacturing the above-mentioned die casting mold, which specifically includes the following steps:

[0042] First, clean the surface of the construction area (including the surface of each layer of panels), and prepare common plastering tools and cutting tools (common handheld hacksaws or automatic cutting machines are both acceptable);

[0043] Then, the nanofiber board with double-sided adhesive is pasted on the construction site of the steel shell, and the aluminum silicate fiber board is fixed on the surface of the nanofiber board;

[0044] Use a plastering tool to evenly apply the prepared adhesive between the surfaces of each layer of the insulation layer, with the bonding area not less than 2 / 3; bond each adjacent polycrystalline fiberboard tightly and tie them firmly;

[0045] After the side walls are assembled, assemble the working layer lining, and place 3 refractory bricks with a thickness of about 30mm in each side wall. Fix the working layer on the inner side of the insulation layer and reserve a gap for the bulk material layer between the two. Use dry masonry to build the working layer lining. Keep the linings tight. For those with large gaps between local linings, use fire mud to fill the gaps between the linings for leveling. Specifically, do not add phosphate binder to the fire mud during construction. In order to ensure the quality of bonding, the adhesive and fire mud are prepared by dedicated personnel as required. Fire mud should be used as soon as it is prepared and should not be left for more than 2 hours.

[0046] Next, silicate particles are used to fill the space between the insulation layer and the working layer to form a bulk layer, and silicate particles are used to fill the gaps around the working layer and the inside of the steel shell;

[0047] Finally, steel clips are used to fix the upper edge of the working layer lining.

Claims

1. A die casting mold, comprising a steel shell (1) and a permanent layer, a heat-insulating layer (4) and a working layer (6) arranged in sequence from the steel shell (1) inward, characterized in that: It also comprises a bulk material layer (5) formed by filling with silicate particles, wherein the bulk material layer (5) is arranged between the thermal insulation layer (4) and the working layer (6); the particle size of the silicate particles in the bulk material layer (5) is 0.02-3.35 mm; and the permanent layer comprises a nanofiber layer (2) and an aluminum silicate fiber layer (3) arranged in sequence from the steel shell (1) inwards.

2. The die casting mold according to claim 1, characterized in that: Among the silicate particles in the bulk material layer (5), the content of particles with a particle size of 0-1 mm is more than 80%.

3. The die casting mold according to claim 2, characterized in that: The silicate particles of the bulk material layer (5) have a composition by mass percentage of SiO2 ≥ 80% and Fe2O3 ≤ 1.0%.

4. The die casting mold according to claim 2, characterized in that: The silicate particles of the bulk material layer (5) have a Mohs hardness of 5-7, a relative density of 2-3, and a melting point of 1700-1750°C.

5. The die casting mold according to claim 1, characterized in that: The nanofiber layer (2) is made of a nanofiber board, and the volume density of the nanofiber board is ≤150Kg / m 3 , SiO2≥60% in the composition by mass percentage; the aluminum silicate fiber layer (3) is made of an aluminum silicate fiber board, and the volume density of the aluminum silicate fiber board is 200-800Kg / m 3 In the composition by mass percentage, SiO2 ≥ 50%, Al2O3 ≥ 20%, and the heating line shrinkage at 1300°C for 24 hours is ≤ 6.0%.

6. The die casting mold according to claim 1, characterized in that: The thermal insulation layer (4) is made of a polycrystalline fiberboard having a volume density of 200-600 Kg / m 3 In the composition by mass percentage, SiO2≤30%, Al2O3≥60%, and the heating line shrinkage at 1300℃ for 24h is ≤1.0%.

7. The die casting mold according to claim 1, characterized in that: The working layer (6) is composed of a silicon working lining plate, wherein the weight percentage composition of the silicon working lining plate is SiO2≥80%, Fe2O3<10%, and the heating line shrinkage at 1300° C. for 24 hours is ≤2.0%.

8. A method for manufacturing a die casting mold according to claims 1-7, characterized in that: The steps include: (1) Pasting the nanofiber board to the construction site of the steel shell, and fixing the aluminum silicate fiber board on the surface of the nanofiber board; (2) Apply the adhesive evenly between the surfaces of each layer of the insulation layer, with the bonding area not less than 2 / 3; bond each adjacent polycrystalline fiberboard tightly and tie them firmly; (3) Assemble the working layer lining and fix it on the inner side of the insulation layer, leaving a gap for the bulk material layer between the two; use dry masonry to build the working layer lining, keep the linings tight, and use fire clay to fill the gaps between the linings for leveling; (4) Silicate particles are used to fill the space between the insulation layer and the working layer to form a bulk layer; (5) Steel clips are used to fix the upper edge of the working layer lining.

Images