Vacuum induction melting composite crucible for inhibiting formation of high-temperature alloy splashing ring

Abstract

The invention belongs to the technical field of high-temperature alloy mother alloy smelting, and particularly relates to a composite crucible for vacuum induction melting for inhibiting formation of a high-temperature alloy splashing ring. The composite crucible sequentially comprises an anti-adhesion functional layer, a thermal stress buffer layer and a structure enhancement layer from inside to outside, the anti-adhesion functional layer adopts a Y2O3-MgO.Al2O3 composite system, and the thickness of the anti-adhesion functional layer is 2-3 mm; the thermal stress buffer layer is made of a gradient composite material, and the thickness is 5-8 mm; the structure reinforcing layer is made of spinel, and the thickness of the structure reinforcing layer is 53-55 mm. The anti-adhesion functional layer is made of a low-surface-energy nano composite material, so that the wettability of the inner surface of the crucible is optimized, and the adhesive force of splashes is reduced; the thermal stress buffer layer realizes thermal shock absorption through a controllable pore structure; the structure reinforcing layer is used for guaranteeing the overall mechanical strength. According to the composite crucible, the phenomenon that the splashing ring is continuously accumulated and thickened in the high-temperature alloy smelting process can be improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of high-temperature alloy master alloy smelting, and particularly relates to a composite crucible for vacuum induction melting for inhibiting formation of high-temperature alloy splashing rings. BACKGROUND

[0002] In the vacuum induction melting process of casting high-temperature alloy, alloy liquid formed by melting of alloy raw materials at high temperature will produce splashing due to electromagnetic stirring, gas escape and other factors. Part of the splashed alloy liquid will adhere to the area above the inner wall of the crucible which is relatively low in temperature, and after cooling, a solid splashing ring will be formed. With the increase of the number of smelting, the splashing ring continuously accumulates and thickens, and when it reaches a certain thickness, it is easy to fall into the molten alloy liquid under the action of its own gravity or vibration and temperature fluctuation in the smelting process, which seriously affects the purity of the high-temperature alloy. At the same time, when the splashing ring accumulates to a certain thickness, it needs to be cleaned, which reduces the service life of the crucible. SUMMARY

[0003] The purpose of the present application is to overcome the deficiencies in the prior art and provide a composite crucible for vacuum induction melting for inhibiting formation of high-temperature alloy splashing rings. The composite crucible of the present application adopts an optimized material and structure, which can effectively reduce the adhesion of splashing material, reduce the formation and accumulation of splashing rings, and can improve the phenomenon of continuous accumulation and thickening of splashing rings in the high-temperature alloy smelting process.

[0004] To achieve the above technical purposes, the technical solution adopted by the embodiments of the present application is as follows: A composite crucible for vacuum induction melting for inhibiting formation of high-temperature alloy splashing rings, comprising, from inside to outside, an anti-adhesion functional layer, a thermal stress buffer layer and a structure enhancement layer; The anti-adhesion functional layer adopts a Y2O3-MgO·Al2O3 composite system, with a thickness of 2-3 mm, and adopts a low-surface-energy nano-composite material to optimize the wettability of the inner surface of the crucible, significantly reducing the contact area and adhesion with the splashing material; The thermal stress buffer layer is made of a gradient composite material, with a thickness of 5-8 mm; heat shock absorption is achieved through a controllable pore structure, and the layer is designed with directional pore channels, with ellipsoidal directional arrangement of pores, which can effectively absorb and disperse thermal stress and prevent the functional layer from peeling off due to thermal shock.

[0005] The structure enhancement layer is made of spinel, with a thickness of 53-55 mm, ensuring the overall mechanical strength.

[0006] Further, the Y2O3-MgO·Al2O3 composite system is a micro-nano hierarchical porous structure, with a pore size range of 5-50 μm and a porosity of 20%-40%, and the content of Y2O3 is 30-40 wt.%, and the content of MgO·Al2O3 is 60-70 wt.%.

[0007] Further, the gradient composite material comprises Y2O3 and spinel, and the content of Y2O3 gradually decreases from inside to outside, while the content of spinel gradually increases.

[0008] Further, from inside to outside, the mass content of Y2O3 in the thermal stress buffer layer is 5%-30%, and the mass content of spinel is 60%-90%.

[0009] Further, the spinel comprises coarse particles, medium particles and fine powder, the particle size of the coarse particles is 3-5mm, the particle size of the medium particles is 1-3mm, and the particle size of the fine powder is ≤1mm.

[0010] Further, the volume fraction of the coarse particles is 10%-20%, the volume fraction of the medium particles is 30%-40%, and the volume fraction of the fine powder is 40%-50%.

[0011] The technical scheme provided by the embodiment of the present application has the following beneficial effects: The design principle of the present application is that the composite crucible adopts a three-layer composite structure, the contact angle of the anti-adhesion function layer in the inner layer with the alloy liquid is greater than 110°, which is much higher than the 60-80° of the traditional crucible material, so that the splashing liquid drops are difficult to wet and spread; the thermal stress buffer layer in the middle layer effectively reduces the interlayer stress and prevents delamination, and the three-layer composite structure crucible can effectively reduce the formation and accumulation of the splashing ring. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 is a sectional view of the composite crucible for vacuum induction melting for inhibiting the formation of a splashing ring of a high-temperature alloy according to the present application.

[0013] Figure 2a is a splashing ring photo of the inner wall of the composite crucible during the melting of INCO713C nickel-based high-temperature alloy in the first furnace in Example 1.

[0014] Figure 2b is a splashing ring photo of the inner wall of the composite crucible during the melting of INCO713C nickel-based high-temperature alloy in the second furnace in Example 1.

[0015] Figure 2c is a splashing ring photo of the inner wall of the composite crucible during the melting of INCO713C nickel-based high-temperature alloy in the third furnace in Example 1.

[0016] Figure 3a is a splashing ring photo of the inner wall of the composite crucible during the melting of INCO713C nickel-based high-temperature alloy in the first furnace in Example 2.

[0017] Figure 3b is a splashing ring photo of the inner wall of the composite crucible during the melting of INCO713C nickel-based high-temperature alloy in the second furnace in Example 2.

[0018] Figure 3c This is a photograph of the splash ring on the inner wall of the composite crucible during the melting of the third batch of INCO713C nickel-based superalloy in Example 2.

[0019] Figure 4a This is a photograph of the splash ring on the inner wall of the composite crucible during the first batch of INCO713C nickel-based superalloy melting in Example 3.

[0020] Figure 4b This is a photograph of the splash ring on the inner wall of the composite crucible during the second batch of INCO713C nickel-based superalloy melting in Example 3.

[0021] Figure 4c This is a photograph of the splash ring on the inner wall of the composite crucible during the melting of the third batch of INCO713C nickel-based superalloy in Example 3.

[0022] Figure 5a This is a photograph of the splash ring on the inner wall of the composite crucible during the first batch of INCO713C nickel-based superalloy melting in the comparative example.

[0023] Figure 5b This is a photograph of the splash ring on the inner wall of the composite crucible during the second batch of INCO713C nickel-based superalloy melting in the comparative example.

[0024] Figure 5c This is a photograph of the splash ring on the inner wall of the composite crucible during the melting of the third batch of INCO713C nickel-based superalloy in the comparative example.

[0025] Explanation of reference numerals in the attached figures: 1-Anti-adhesion functional layer, 2-Thermal stress buffer layer, 3-Structural reinforcement layer. Detailed Implementation

[0026] The following describes in detail, with reference to embodiments and accompanying drawings, a composite crucible for vacuum induction melting that suppresses the formation of high-temperature alloy splash rings.

[0027] Example 1 like Figure 1 As shown, a composite crucible for vacuum induction melting that suppresses the formation of high-temperature alloy splash rings includes, from the inside out, an anti-adhesion functional layer 1, a thermal stress buffer layer 2, and a structural reinforcement layer 3. The anti-adhesion functional layer 1 adopts a Y2O3-MgO·Al2O3 composite system with a thickness of 3mm; wherein the Y2O3 content is 38wt.%, the MgO·Al2O3 content is 60wt.%, and the balance is refractory material impurities. The thermal stress buffer layer 2 is made of a gradient composite material with a thickness of 5 mm. The gradient composite material includes Y2O3 and spinel, with the Y2O3 content decreasing from 28% to 7% and the spinel mass content increasing from 67% to 89%. The structure reinforcing layer 3 is made of spinel and has a thickness of 55 mm.

[0028] The spinel in the thermal stress buffer layer 2 and the structure reinforcing layer 3 comprises coarse particles with a particle size of 3-5 mm, medium particles with a particle size of 1-3 mm and fine powder with a particle size of ≤1 mm, wherein the volume fraction of the coarse particles is 17%, the volume fraction of the medium particles is 36% and the volume fraction of the fine powder is 47%.

[0029] The INCO713C nickel-based superalloy is refined by using the above-mentioned composite crucible, the refining temperature of the INCO713C nickel-based superalloy is 1510-1530℃, three batches of alloys are successively smelted, and the inner wall of the crucible near the alloy liquid surface is photographed before pouring.

[0030] The specific alloy component range and measured values of each batch of INCO713C nickel-based superalloy are shown in Table 1.

[0031] Table 1 Chemical component range of INCO713C nickel-based superalloy and measured values of each batch in the example (wt.%)

[0032] Through this process, the first batch (see Figure 2a ), the second batch (see Figure 2b ) and the third batch (see Figure 2c ) of INCO713C alloy ingots do not have splashing rings.

[0033] Example 2 As shown in Figure 1 , a composite crucible for vacuum induction melting for suppressing the formation of splashing rings of high-temperature alloy comprises, from inside to outside, an anti-adhesion functional layer 1, a thermal stress buffer layer 2 and a structure reinforcing layer 3; The anti-adhesion functional layer 1 is made of a Y2O3-MgO·Al2O3 composite system and has a thickness of 3 mm; wherein the content of Y2O3 is 36wt.%, the content of MgO·Al2O3 is 63wt.% and the balance is impurities of refractory materials; The thermal stress buffer layer 2 is made of a gradient composite material and has a thickness of 6 mm; The gradient composite material comprises Y2O3 and spinel, the content of Y2O3 decreases from 29% to 5%, and the mass content of spinel increases from 65% to 90%; The structure reinforcing layer 3 is made of spinel and has a thickness of 53 mm; The spinel in the thermal stress buffer layer 2 and the structure reinforcing layer 3 comprises coarse particles with a particle size of 3-5 mm, medium particles with a particle size of 1-3 mm and fine powder with a particle size of ≤1 mm, wherein the volume fraction of the coarse particles is 16%, the volume fraction of the medium particles is 37% and the volume fraction of the fine powder is 47%.

[0034] The INCO713C nickel-based superalloy was refined by using the composite crucible, the refining temperature of the INCO713C nickel-based superalloy was 1510-1530℃, three batches of alloys were successively smelted, and the inner wall photos near the alloy liquid surface in the crucible were taken before pouring.

[0035] The specific alloy composition range and measured values of each batch of INCO713C nickel-based superalloy are shown in Table 2.

[0036] Table 2 Chemical composition range of INCO713C nickel-based superalloy and measured values of each batch in Example 2 (wt.%)

[0037] Through this process, the first batch (see Figure 3a ), the second batch (see Figure 3b ), and the third batch (see Figure 3c ) of INCO713C alloy ingots did not have splashing rings.

[0038] Example 3 As shown in Figure 1 , a composite crucible for vacuum induction melting to inhibit the formation of splashing rings of high-temperature alloy comprises, from the inside to the outside, an anti-adhesion functional layer 1, a thermal stress buffer layer 2, and a structure enhancement layer 3; The anti-adhesion functional layer 1 adopts a Y2O3-MgO·Al2O3 composite system, with a thickness of 2mm; the content of Y2O3 is 35wt.%, the content of MgO·Al2O3 is 60wt.%, and the balance is refractory material impurities; The thermal stress buffer layer 2 is made of a gradient composite material, with a thickness of 8mm; the gradient composite material comprises Y2O3 and spinel, the content of Y2O3 decreases from 28% to 6%, and the mass content of spinel increases from 62% to 87%; The structure enhancement layer 3 is made of spinel, with a thickness of 57mm; The spinel in the thermal stress buffer layer 2 and the structure enhancement layer 3 comprises coarse particles with a particle size of 3-5mm, medium particles with a particle size of 1-3mm, and fine powder with a particle size of ≤1mm, wherein the volume fraction of coarse particles is 15%, the volume fraction of medium particles is 37%, and the volume fraction of fine powder is 48%.

[0039] The INCO713C nickel-based superalloy was refined by using the composite crucible, the refining temperature of the INCO713C nickel-based superalloy was 1510-1530℃, three batches of alloys were successively smelted, and the inner wall photos near the alloy liquid surface in the crucible were taken before pouring.

[0040] The specific alloy composition range and measured values of each batch of INCO713C nickel-based superalloy are shown in Table 3.

[0041] Table 3 INCO713C nickel-based superalloy chemical composition range and measured values of each furnace in Example 3 (wt. %)

[0042] Through this process, the first furnace (see Figure 4a ), the second furnace (see Figure 4b ), and the third furnace (see Figure 4c ) of the INCO713C alloy ingot did not appear splash ring.

[0043] Comparative Example A conventional crucible was used, which was an alumina crucible with a thickness of 24 mm, and the mass content of Al2O3 was 98%, and the balance was impurities.

[0044] The INCO713C nickel-based superalloy was refined using the above conventional crucible, and the refining temperature of the INCO713C nickel-based superalloy was 1510-1530℃, and three furnaces of alloy were successively melted, and the inner wall of the crucible near the alloy liquid surface was photographed before pouring.

[0045] The specific alloy composition range and measured values of each furnace of the INCO713C nickel-based superalloy are shown in Table 4.

[0046] Table 4 INCO713C nickel-based superalloy chemical composition range and measured values of each furnace in the comparative example (wt. %)

[0047] Through this process, the first furnace (see Figure 5a ), the second furnace (see Figure 5b ) of the INCO713C alloy ingot did not appear splash ring, and the third furnace (see Figure 5c ) appeared splash ring.

[0048] Under the same other conditions, the splash ring on the inner wall of the crucible of the INCO713C alloy ingot was recorded by Example 1, Example 2, Example 3, and the comparative example, and the photographed splash ring photos of the inner wall of the crucible are shown in Figures 3-5. It can be seen that the composite crucible in Examples 1-3 of the present application is used to melt the master alloy INCO713C nickel-based superalloy, which can effectively delay the time of the appearance of the splash ring on the inner wall of the crucible.

[0049] Finally, it should be noted that the above is only a preferred embodiment of the present application, and does not limit the present application in any way. Any simple modification, change, and equivalent change of the above embodiment according to the essence of the present application still falls within the protection scope of the technical solution of the present application.

Claims

1. A composite crucible for vacuum induction melting that suppresses the formation of high-temperature alloy splash rings, characterized in that, From the inside out, it includes an anti-adhesion functional layer (1), a thermal stress buffer layer (2), and a structural reinforcement layer (3). The anti-adhesion functional layer (1) adopts a Y2O3-MgO·Al2O3 composite system with a thickness of 2-3 mm; the thermal stress buffer layer (2) is made of gradient composite material with a thickness of 5-8 mm. The structural reinforcement layer (3) is made of spinel and has a thickness of 53-55 mm.

2. The composite crucible for vacuum induction melting according to claim 1, characterized in that, The Y2O3-MgO·Al2O3 composite system is a micro-nano hierarchical porous structure with a pore size range of 5-50 μm and a porosity of 20%-40%. By mass fraction, the content of Y2O3 is 30-40 wt.% and the content of MgO·Al2O3 is 60-70 wt.%.

3. The composite crucible for vacuum induction melting according to claim 1, characterized in that, The gradient composite material includes Y2O3 and spinel, with the Y2O3 content gradually decreasing from the inside to the outside, while the spinel content gradually increases.

4. The composite crucible for vacuum induction melting according to claim 3, characterized in that, From the inside out, the thermal stress buffer layer (2) contains 5%-30% Y2O3 and 60%-90% spinel.

5. The composite crucible for vacuum induction melting according to claim 1 or 3, characterized in that, The spinel comprises coarse particles, medium particles, and fine powder. The coarse particles have a particle size of 3-5 mm, the medium particles have a particle size of 1-3 mm, and the fine powder has a particle size of ≤1 mm.

6. The composite crucible for vacuum induction melting according to claim 5, characterized in that, The volume fraction of the coarse particles is 10%-20%, the volume fraction of the medium particles is 30%-40%, and the volume fraction of the fine powder is 40%-50%.

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