Black quartz boat and production method thereof

Abstract

The invention discloses a black quartz boat and a production method thereof, and relates to the technical field of quartz material preparation, and the black quartz boat is formed by welding a black quartz plate and a black quartz tube; the black quartz plate and the black quartz tube are independently prepared from the following raw materials in percentage by weight: 1wt%-4wt% of an additive and the balance of high-purity quartz sand; the additive is prepared from the following components in parts by weight: 0.6 to 1 part of rare earth oxide, 2 to 3 parts of ferric nitrate, 1 to 3 parts of manganous nitrate, 1 to 1.5 parts of cobalt nitrate, 0.1 to 0.3 part of zinc nitrate, 0.05 to 0.08 part of molybdenum nitrate, 0.05 to 0.1 part of vanadium pentoxide and 0.03 to 0.05 part of hafnium oxide. The black quartz boat is good in color uniformity, sufficient in high temperature resistance and good in welding quality.

Description

Technical Field

[0001] The present invention relates to the technical field of quartz material preparation, and particularly relates to a black quartz boat and a production method thereof. Background Art

[0002] In the semiconductor and photovoltaic industries, the quartz boat, as a key carrier and reaction vessel, its performance directly affects the product quality and production efficiency. With the continuous development of the industry, the performance requirements for the quartz boat are also increasing day by day. Traditional quartz boats are mostly transparent or semi-transparent. Their thermal radiation characteristics in high-temperature environments are not conducive to the efficient utilization of energy. They are prone to cracking at high temperatures, and cannot achieve functions such as light shielding and ultraviolet protection, making it difficult to meet the requirements of advanced processes. It is in this situation that the black quartz boat came into being, and its appearance has attracted wide attention in the industry.

[0003] Existing black quartz boats mostly achieve the blackening effect by carbon doping or coloring. However, carbon is prone to oxidation and volatilization above 1500°C, which in turn leads to surface pulverization. When using coloring, due to the high risk of metal ion migration pollution and the temperature resistance limit is only 1800°C. In some high-temperature processes, such as the high-temperature sintering process of some semiconductor materials, it is required that the black quartz boat can withstand temperatures above 2000°C and maintain structural stability. However, many existing black quartz boats are prone to problems such as softening and deformation at such high temperatures, seriously affecting their service life and production stability. In addition, in the manufacturing process of black quartz boats, traditional welding methods, such as ordinary arc welding, are prone to impurity residues and pores at the welds, affecting the overall strength and sealing performance of the quartz boat, and it is difficult to meet the requirements of high-precision production processes for quartz boats.

[0004] To solve the above problems, the Chinese invention patent with the application publication number CN118652043A discloses a method for preparing a new type of high-temperature resistant quartz boat, including the following steps: S1 magnetic separation, putting the raw material quartz sand into a magnetic separator for preliminary magnetic separation; S2 flotation, adding the magnetically separated materials into the flotation machine according to different flotation particle sizes; S3 pickling, putting the quartz sand in the intermediate buffer tank into a reaction kettle, and feeding in a certain amount of hydrochloric acid, nitric acid, and hydrofluoric acid; S4 chlorination, transporting the dried sand to a calcination furnace for calcination and heating, and then connecting it to a chlorination furnace, and selecting the chlorination temperature according to the particle size; S5 melting, putting the high-purity quartz sand into a melting furnace to melt it into a quartz plate, and then welding the quartz plates into a quartz boat; this invention uses flotation, pickling, chlorination, and magnetic separation processes in the process of the raw material quartz sand for producing the quartz boat to control the impurity content of the quartz sand and improve the high-temperature resistance. However, this quartz boat is not black, cannot achieve the functions of light shielding and ultraviolet protection, and it is also difficult to withstand temperatures above 2000°C.

[0005] It can be seen that there is still a need in this field for a black quartz boat with good color uniformity, sufficient high-temperature resistance performance, and excellent welding quality, as well as a production method therefor. Summary of the Invention

[0006] The purpose of the present invention is to provide a black quartz boat with good color uniformity, sufficient high-temperature resistance performance, and excellent welding quality, as well as a production method therefor, in order to overcome the deficiencies of the prior art.

[0007] To achieve the above object, the technical solution adopted by the present invention is: a black quartz boat is formed by welding a black quartz plate and a black quartz tube; the black quartz plate and the black quartz tube are independently made of the following raw materials by weight percentage: 1 wt% - 4 wt% of an additive, and the balance is high-purity quartz sand; the additive includes the following components in parts by weight: 0.6 - 1 part of rare earth oxide, 2 - 3 parts of iron nitrate, 1 - 3 parts of manganese nitrate, 1 - 1.5 parts of cobalt nitrate, 0.1 - 0.3 part of zinc nitrate, 0.05 - 0.08 part of molybdenum nitrate, 0.05 - 0.1 part of vanadium pentoxide, and 0.03 - 0.05 part of hafnium oxide.

[0008] Preferably, the welding adopts plasma arc welding + oxy-hydrogen flame welding. During the welding process, the plasma arc provides a high-temperature heat source to quickly melt the quartz material, while the oxy-hydrogen mixture provides a reducing atmosphere during combustion, effectively reducing oxidation and impurity residues at the weld.

[0009] Preferably, the welding electrode used includes the following components by weight percentage: 0.5 - 2% of cerium oxide, 1 - 3% of high-purity nano-silicon powder, and the balance is silicon dioxide.

[0010] Preferably, the average particle size of the high-purity quartz sand is 30 - 100 mesh.

[0011] Preferably, the impurity content in the high-purity quartz sand is less than 10 ppm, and the silicon dioxide content is greater than 99.998 wt%.

[0012] Preferably, the average particle size of the high-purity nano-silicon powder is 30 - 100 nm, and the purity is ≥ 99.9%.

[0013] Preferably, the particle size of the silicon dioxide is 100 - 200 mesh; the particle size of the cerium oxide is 150 - 300 mesh.

[0014] Preferably, the rare earth oxide is a mixture of neodymium oxide, yttrium oxide, lanthanum oxide, and scandium oxide in a mass ratio of 1:(0.8 - 1.2):1:(0.2 - 0.4).

[0015] Another object of the present invention is to provide a production method for the black quartz boat, including the following steps: Step S1, production of black quartz plate and black quartz tube: rare earth oxide, vanadium pentoxide and hafnium oxide are added with acid to dissolve them to prepare an acidic solution; iron nitrate, manganese nitrate, cobalt nitrate, zinc nitrate and molybdenum nitrate are dissolved in water to prepare an aqueous solution; the above two solutions are mixed with high-purity quartz sand, and then heated to 1200°C in a sand baking machine for drying and expansion, and then screened and magnetically separated to remove metal impurities, and then put into a continuous melting furnace for smelting, respectively drawn into shape, and annealed to obtain black quartz plate and black quartz tube respectively; Step S2, welding: processing blind holes that have not been penetrated at the welding positions of the upper and lower black quartz plates to form a mechanical limit structure, then inserting the black quartz tube into the blind hole, and welding by plasma arc welding + oxyhydrogen flame welding; Step S3, post-processing: After welding is completed, the weld is ground and polished to make its surface smooth and flat.

[0016] Preferably, the acid in step S1 is hydrochloric acid, and its mass percentage concentration is 36% to 38%; the mass ratio of the rare earth oxide to the acid is 1:(1-3); and the mass ratio of the ferric nitrate to water is 1:(3-5).

[0017] Preferably, the smelting temperature in step S1 is 2100-2200° C., and the smelting time is 1-3 h.

[0018] Preferably, the annealing temperature in step S1 is 550-650° C., and the holding time is 1-2 h.

[0019] Preferably, the plasma current of the plasma arc welding in step S2 is 100-120A, with argon protection; the hydrogen-oxygen mixed gas flow ratio of the oxyhydrogen flame welding is 1:1.5, and the welding speed is 8 mm / s.

[0020] Due to the application of the above technical solution, the present invention has the following beneficial effects: (1) The production method of the black quartz boat disclosed in the present invention has simple process, convenient operation and control, high production efficiency and finished product qualification rate, strong equipment versatility, greatly reduced equipment purchase and maintenance costs, easy large-scale industrial production, little impact on the environment, and high promotion and application value.

[0021] (2) The black quartz boat disclosed by the present invention is formed by welding a black quartz plate and a black quartz tube; the black quartz plate and the black quartz tube are independently made of the following raw materials by weight percentage: 1wt%-4wt% of an additive, and the balance is high-purity quartz sand; the additive includes the following components in parts by weight: 0.6-1 part of rare earth oxide, 2-3 parts of ferric nitrate, 1-3 parts of manganese nitrate, 1-1.5 parts of cobalt nitrate, 0.1-0.3 part of zinc nitrate, 0.05-0.08 part of molybdenum nitrate, 0.05-0.1 part of vanadium pentoxide, and 0.03-0.05 part of hafnium oxide. By reasonably selecting the composition and dosage ratio of the additive, the made black quartz boat has good color uniformity, stable optical properties, and sufficient high-temperature resistance; the multi-elements such as rare earth elements, iron, manganese, cobalt, zinc, molybdenum, vanadium, and hafnium are introduced for the first time to assist in color development synergistically. They cooperate with each other to make the color of the black quartz boat more pure and uniform, and better achieve the required low light transmittance effect.

[0022] (3) For the black quartz boat disclosed by the present invention, the welding adopts plasma arc welding + oxy-hydrogen flame welding. During the welding process, the plasma arc provides a high-temperature heat source to quickly melt the quartz material, while the oxy-hydrogen mixture provides a reducing atmosphere during combustion, effectively reducing oxidation and impurity residues at the weld; the combination of the two welding methods significantly improves the weld quality. The strength and sealing performance at the weld are good, effectively reducing problems such as leakage and structural instability caused by weld problems, and improving the overall quality and service life of the quartz boat; the welding electrode used for the welding includes the following components by weight percentage: 0.5-2% of cerium oxide, 1-3% of high-purity nano-silicon powder, and the balance is silicon dioxide; and when welding, non-penetrating blind holes are processed for limiting, which can further improve the welding quality, enhance the high-temperature resistance of the quartz boat, and effectively extend its service life.

[0023] (4) For the black quartz boat disclosed by the present invention, by reasonably selecting the production process parameters, the made black quartz boat has better color uniformity, higher light absorption rate, more sufficient high-temperature resistance, and better welding quality. Specific Embodiments

[0024] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations.

[0025] Example 1

[0026] A black quartz boat is welded by a black quartz plate and a black quartz tube; the black quartz plate and the black quartz tube are independently made of the following raw materials in weight percentage: 1wt% of additives and the balance of high-purity quartz sand; the additives include the following components in weight parts: 0.6 parts of rare earth oxides, 2 parts of ferric nitrate, 1 part of manganese nitrate, 1 part of cobalt nitrate, 0.1 parts of zinc nitrate, 0.05 parts of molybdenum nitrate, 0.05 parts of vanadium pentoxide, and 0.03 parts of hafnium oxide.

[0027] The welding adopts plasma arc welding + hydrogen-oxygen flame welding. During the welding process, the plasma arc provides a high-temperature heat source to quickly melt the quartz material, and the hydrogen-oxygen mixture provides a reducing atmosphere during the combustion process, effectively reducing oxidation and impurity residues at the weld; the welding rod used in the welding includes the following components in weight percentage: 0.5% cerium oxide, 1% high-purity nano silicon powder, and the balance is silicon dioxide; the average particle size of the high-purity quartz sand is 30 meshes; the impurity content in the high-purity quartz sand is less than 10ppm, and the silicon dioxide content is greater than 99.998wt%.

[0028] The average particle size of the high-purity nano-silicon powder is 30nm, and the purity is ≥99.9%; the particle size of the silicon dioxide is 100 mesh; the particle size of the cerium oxide is 150 mesh; the rare earth oxide is a mixture of neodymium oxide, yttrium oxide, lanthanum oxide, and scandium oxide in a mass ratio of 1:0.8:1:0.2.

[0029] A method for producing the black quartz boat comprises the following steps: Step S1, production of black quartz plate and black quartz tube: rare earth oxide, vanadium pentoxide and hafnium oxide are added with acid to dissolve them to prepare an acidic solution; iron nitrate, manganese nitrate, cobalt nitrate, zinc nitrate and molybdenum nitrate are dissolved in water to prepare an aqueous solution; the above two solutions are mixed with high-purity quartz sand, and then heated to 1200°C in a sand baking machine for drying and expansion, and then screened and magnetically separated to remove metal impurities, and then put into a continuous melting furnace for smelting, respectively drawn into shape, and annealed to obtain black quartz plate and black quartz tube respectively; Step S2, welding: processing blind holes that have not been penetrated at the welding positions of the upper and lower black quartz plates to form a mechanical limit structure, then inserting the black quartz tube into the blind hole, and welding by plasma arc welding + oxyhydrogen flame welding; Step S3, post-processing: After welding is completed, the weld is ground and polished to make its surface smooth and flat.

[0030] The acid in step S1 is hydrochloric acid, and its mass percentage concentration is 36%; the mass ratio of the rare earth oxide and the acid is 1:1; the mass ratio of the ferric nitrate and water is 1:3; the smelting temperature in step S1 is 2100°C, and the smelting time is 1h; the annealing temperature in step S1 is 550°C, and the holding time is 1h; the plasma current of the plasma arc welding in step S2 is 100A, and the argon gas protection is used; the hydrogen-oxygen mixed gas flow ratio of the oxyhydrogen flame welding is 1:1.5, and the welding speed is 8mm / s.

[0031] Example 2

[0032] A black quartz boat is welded by a black quartz plate and a black quartz tube; the black quartz plate and the black quartz tube are independently made of the following raw materials in percentage by weight: 2wt% of additives and the balance of high-purity quartz sand; the additives include the following components in parts by weight: 0.7 parts of rare earth oxide, 2.3 parts of ferric nitrate, 1.5 parts of manganese nitrate, 1.2 parts of cobalt nitrate, 0.15 parts of zinc nitrate, 0.06 parts of molybdenum nitrate, 0.06 parts of vanadium pentoxide and 0.035 parts of hafnium oxide.

[0033] The welding adopts plasma arc welding + hydrogen-oxygen flame welding. During the welding process, the plasma arc provides a high-temperature heat source to melt the quartz material quickly, and the hydrogen-oxygen mixture provides a reducing atmosphere during the combustion process, effectively reducing oxidation and impurity residues at the weld; the welding rod used in the welding includes the following components in weight percentage: 1% cerium oxide, 1.5% high-purity nano silicon powder, and the balance is silicon dioxide; the average particle size of the high-purity quartz sand is 50 mesh; the impurity content in the high-purity quartz sand is less than 10ppm, and the silicon dioxide content is greater than 99.998wt%; the average particle size of the high-purity nano silicon powder is 50nm, and the purity is ≥99.9%; the particle size of the silicon dioxide is 130 mesh; the particle size of the cerium oxide is 200 mesh; the rare earth oxide is a mixture of neodymium oxide, yttrium oxide, lanthanum oxide, and scandium oxide in a mass ratio of 1:0.9:1:0.25.

[0034] A method for producing the black quartz boat comprises the following steps: Step S1, production of black quartz plate and black quartz tube: rare earth oxide, vanadium pentoxide and hafnium oxide are added with acid to dissolve them to prepare an acidic solution; iron nitrate, manganese nitrate, cobalt nitrate, zinc nitrate and molybdenum nitrate are dissolved in water to prepare an aqueous solution; the above two solutions are mixed with high-purity quartz sand, and then heated to 1200°C in a sand baking machine for drying and expansion, and then screened and magnetically separated to remove metal impurities, and then put into a continuous melting furnace for smelting, respectively drawn into shape, and annealed to obtain black quartz plate and black quartz tube respectively; Step S2, Welding: Process blind holes that do not penetrate at the welding positions of the upper and lower black quartz plates to form a mechanical limit structure. Then insert the black quartz tube into the blind hole and perform welding using plasma arc welding + oxy-hydrogen flame welding; Step S3, Post-processing: After welding, grind and polish the weld to make its surface smooth and flat.

[0035] The acid described in Step S1 is hydrochloric acid, and its mass percentage concentration is 36.5%; the mass ratio of the rare earth oxide to the acid is 1:1.5; the mass ratio of ferric nitrate to water is 1:3.5; the melting temperature in Step S1 is 2130 °C, and the melting time is 1.5 h; the annealing temperature in Step S1 is 570 °C, and the heat preservation time is 1.2 h; the plasma current of the plasma arc welding in Step S2 is 105 A, with argon protection; the flow ratio of the oxy-hydrogen mixture gas of the oxy-hydrogen flame welding is 1:1.5, and the welding speed is 8 mm / s.

[0036] Example 3

[0037] A black quartz boat is welded by a black quartz plate and a black quartz tube; the black quartz plate and the black quartz tube are independently made of the following raw materials by weight percentage: 2.5 wt% of additives, and the balance is high-purity quartz sand; the additives include the following components by weight: 0.8 part of rare earth oxide, 2.5 parts of ferric nitrate, 2 parts of manganese nitrate, 1.3 parts of cobalt nitrate, 0.2 part of zinc nitrate, 0.065 part of molybdenum nitrate, 0.075 part of vanadium pentoxide, and 0.04 part of hafnium oxide.

[0038] The welding uses plasma arc welding + oxy-hydrogen flame welding. During the welding process, the plasma arc provides a high-temperature heat source to quickly melt the quartz material, while the oxy-hydrogen mixture gas provides a reducing atmosphere during combustion, effectively reducing oxidation and impurity residues at the weld; the welding electrode used includes the following components by weight percentage: 1.2% of cerium oxide, 2% of high-purity nano-silicon powder, and the balance is silicon dioxide; the average particle size of the high-purity quartz sand is 70 mesh; the impurity content in the high-purity quartz sand is less than 10 ppm, and the silicon dioxide content is greater than 99.998 wt%; the average particle size of the high-purity nano-silicon powder is 70 nm, and the purity is ≥99.9%; the particle size of the silicon dioxide is 150 mesh; the particle size of the cerium oxide is 230 mesh; the rare earth oxide is a mixture of neodymium oxide, yttrium oxide, lanthanum oxide, and scandium oxide in a mass ratio of 1:1:1:0.3.

[0039] A production method of the black quartz boat includes the following steps: Step S1, production of black quartz plate and black quartz tube: rare earth oxide, vanadium pentoxide and hafnium oxide are added with acid to dissolve them to prepare an acidic solution; iron nitrate, manganese nitrate, cobalt nitrate, zinc nitrate and molybdenum nitrate are dissolved in water to prepare an aqueous solution; the above two solutions are mixed with high-purity quartz sand, and then heated to 1200°C in a sand baking machine for drying and expansion, and then screened and magnetically separated to remove metal impurities, and then put into a continuous melting furnace for smelting, respectively drawn into shape, and annealed to obtain black quartz plate and black quartz tube respectively; Step S2, welding: processing blind holes that have not been penetrated at the welding positions of the upper and lower black quartz plates to form a mechanical limit structure, then inserting the black quartz tube into the blind hole, and welding by plasma arc welding + oxyhydrogen flame welding; Step S3, post-processing: After welding is completed, the weld is ground and polished to make its surface smooth and flat.

[0040] The acid in step S1 is hydrochloric acid, and its mass percentage concentration is 37%; the mass ratio of the rare earth oxide to the acid is 1:2; the mass ratio of the ferric nitrate to water is 1:4; the smelting temperature in step S1 is 2150°C, and the smelting time is 2h; the annealing temperature in step S1 is 600°C, and the holding time is 1.5h; the plasma current of the plasma arc welding in step S2 is 110A, and the argon gas protection is used; the hydrogen-oxygen mixed gas flow ratio of the oxyhydrogen flame welding is 1:1.5, and the welding speed is 8mm / s.

[0041] Example 4

[0042] A black quartz boat is welded by a black quartz plate and a black quartz tube; the black quartz plate and the black quartz tube are independently made of the following raw materials in percentage by weight: 3.5wt% additive and the balance high-purity quartz sand; the additive comprises the following components in parts by weight: 0.9 parts of rare earth oxide, 2.8 parts of ferric nitrate, 2.5 parts of manganese nitrate, 1.4 parts of cobalt nitrate, 0.25 parts of zinc nitrate, 0.075 parts of molybdenum nitrate, 0.09 parts of vanadium pentoxide and 0.045 parts of hafnium oxide.

[0043] The welding adopts plasma arc welding + hydrogen-oxygen flame welding. During the welding process, the plasma arc provides a high-temperature heat source to melt the quartz material quickly, and the hydrogen-oxygen mixture provides a reducing atmosphere during the combustion process, effectively reducing oxidation and impurity residues at the weld; the welding rod used in the welding includes the following components in weight percentage: 1.8% cerium oxide, 2.5% high-purity nano silicon powder, and the balance is silicon dioxide; the average particle size of the high-purity quartz sand is 90 mesh; the impurity content in the high-purity quartz sand is less than 10ppm, and the silicon dioxide content is greater than 99.998wt%; the average particle size of the high-purity nano silicon powder is 90nm, and the purity is ≥99.9%; the particle size of the silicon dioxide is 180 mesh; the particle size of the cerium oxide is 280 mesh; the rare earth oxide is a mixture of neodymium oxide, yttrium oxide, lanthanum oxide, and scandium oxide in a mass ratio of 1:1.1:1:0.35.

[0044] A method for producing the black quartz boat comprises the following steps: Step S1, production of black quartz plate and black quartz tube: rare earth oxide, vanadium pentoxide and hafnium oxide are added with acid to dissolve them to prepare an acidic solution; iron nitrate, manganese nitrate, cobalt nitrate, zinc nitrate and molybdenum nitrate are dissolved in water to prepare an aqueous solution; the above two solutions are mixed with high-purity quartz sand, and then heated to 1200°C in a sand baking machine for drying and expansion, and then screened and magnetically separated to remove metal impurities, and then put into a continuous melting furnace for smelting, respectively drawn into shape, and annealed to obtain black quartz plate and black quartz tube respectively; Step S2, welding: processing blind holes that have not been penetrated at the welding positions of the upper and lower black quartz plates to form a mechanical limit structure, then inserting the black quartz tube into the blind hole, and welding by plasma arc welding + oxyhydrogen flame welding; Step S3, post-processing: After welding is completed, the weld is ground and polished to make its surface smooth and flat.

[0045] The acid in step S1 is hydrochloric acid, and its mass percentage concentration is 37.5%; the mass ratio of the rare earth oxide to the acid is 1:2.5; the mass ratio of the ferric nitrate to water is 1:4.5; the smelting temperature in step S1 is 2180°C, and the smelting time is 2.5h; the annealing temperature in step S1 is 630°C, and the holding time is 1.8h; the plasma current of the plasma arc welding in step S2 is 115A, and the argon gas protection is used; the hydrogen-oxygen mixed gas flow ratio of the oxyhydrogen flame welding is 1:1.5, and the welding speed is 8mm / s.

[0046] Example 5

[0047] A black quartz boat is welded by a black quartz plate and a black quartz tube; the black quartz plate and the black quartz tube are independently made of the following raw materials in percentage by weight: 4wt% of additives and the balance of high-purity quartz sand; the additives include the following components in parts by weight: 1 part of rare earth oxide, 3 parts of ferric nitrate, 3 parts of manganese nitrate, 1.5 parts of cobalt nitrate, 0.3 parts of zinc nitrate, 0.08 parts of molybdenum nitrate, 0.1 parts of vanadium pentoxide and 0.05 parts of hafnium oxide.

[0048] The welding adopts plasma arc welding + hydrogen-oxygen flame welding. During the welding process, the plasma arc provides a high-temperature heat source to melt the quartz material quickly, and the hydrogen-oxygen mixture provides a reducing atmosphere during the combustion process, effectively reducing oxidation and impurity residues at the weld; the welding rod used in the welding includes the following components in weight percentage: 2% cerium oxide, 3% high-purity nano silicon powder, and the balance is silicon dioxide; the average particle size of the high-purity quartz sand is 100 mesh; the impurity content in the high-purity quartz sand is less than 10ppm, and the silicon dioxide content is greater than 99.998wt%; the average particle size of the high-purity nano silicon powder is 100nm, and the purity is ≥99.9%; the particle size of the silicon dioxide is 200 mesh; the particle size of the cerium oxide is 300 mesh; the rare earth oxide is a mixture of neodymium oxide, yttrium oxide, lanthanum oxide, and scandium oxide in a mass ratio of 1:1.2:1:0.4.

[0049] A method for producing the black quartz boat comprises the following steps: Step S1, production of black quartz plate and black quartz tube: rare earth oxide, vanadium pentoxide and hafnium oxide are added with acid to dissolve them to prepare an acidic solution; iron nitrate, manganese nitrate, cobalt nitrate, zinc nitrate and molybdenum nitrate are dissolved in water to prepare an aqueous solution; the above two solutions are mixed with high-purity quartz sand, and then heated to 1200°C in a sand baking machine for drying and expansion, and then screened and magnetically separated to remove metal impurities, and then put into a continuous melting furnace for smelting, respectively drawn into shape, and annealed to obtain black quartz plate and black quartz tube respectively; Step S2, welding: processing blind holes that have not been penetrated at the welding positions of the upper and lower black quartz plates to form a mechanical limit structure, then inserting the black quartz tube into the blind hole, and welding by plasma arc welding + oxyhydrogen flame welding; Step S3, post-processing: After welding is completed, the weld is ground and polished to make its surface smooth and flat.

[0050] In step S1, the acid is hydrochloric acid with a mass percentage concentration of 38%; the mass ratio of the rare earth oxide to the acid is 1:3; the mass ratio of ferric nitrate to water is 1:5; the melting temperature in step S1 is 2200 °C and the melting time is 3 h; the annealing temperature in step S1 is 650 °C and the heat preservation time is 2 h; in step S2, the plasma current of the plasma arc welding is 120 A with argon protection; the flow ratio of the hydrogen-oxygen mixed gas for the hydrogen-oxygen flame welding is 1:1.5 and the welding speed is 8 mm / s.

[0051] Comparative Example 1 A black quartz boat and its production method are basically the same as those in Example 1, except that vanadium pentoxide is not added, the rare earth oxide is cerium oxide, and the welding is carried out by hydrogen-oxygen flame welding.

[0052] Comparative Example 2 A black quartz boat and its production method are basically the same as those in Example 1, except that hafnium oxide and high-purity nano-silicon powder are not added, and the welding is carried out by plasma arc welding.

[0053] To further illustrate the beneficial technical effects of the black quartz boats involved in the embodiments of the present invention, relevant performance tests were carried out on the black quartz boats involved in Examples 1-5 and Comparative Examples 1-2. The test results are shown in Table 1, and the test methods are as follows: (1) Test method for color uniformity and color difference (ΔE): A high-precision color difference meter (CIELAB system) equipped with an integrating sphere attachment to eliminate the influence of surface reflection is used; based on the CIELAB color space, by measuring the L* (lightness), a* (red-green axis), and b* (yellow-blue axis) values of the sample, the color difference ΔE is calculated: , calibrated with a standard white board; randomly select 5 test points on the surface of the sample, measure each point 3 times, calculate the ΔE value of each point from the reference point, and take the maximum value as the final result; (2) High-temperature resistance performance: Place the black quartz boat samples of each example in a high-temperature furnace, heat them to 2000 °C at a heating rate of 10 °C / min and keep for 1 hour. During the heating process, observe the structural changes of the quartz boat in real time through a high-temperature camera; if there are no obvious softening, deformation and other problems, the high-temperature resistance performance is qualified, otherwise it is unqualified.

[0054] (3) Welding quality: Conduct an external inspection on the welds of the black quartz boats of each example to observe whether the welds are flat, whether there are defects such as pores and cracks; then use an ultrasonic flaw detector to conduct an internal flaw detection on the welds to detect the internal defect conditions of the welds; if the external inspection results show that the weld surface is flat and smooth, without obvious pores and cracks and other defects, and the ultrasonic flaw detection results show that no obvious defects are found inside the weld, the welding quality is good; otherwise it fails.

[0055]

[0056] As can be seen from Table 1, the black quartz boats involved in the embodiments of the present invention have better color uniformity, better high-temperature resistance, and more excellent welding quality compared with the products of the comparative examples; the combined use of vanadium pentoxide, rare earth oxides, hafnium oxide, high-purity nano-silicon powder, oxy-hydrogen flame welding, and plasma arc welding is beneficial to improving the above-mentioned properties.

[0057] The above embodiments are only used to illustrate the technical concept and features of the present invention, and the purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A black quartz boat, characterized in that, It is welded by a black quartz plate and a black quartz tube; the black quartz plate and the black quartz tube are independently made of the following raw materials in weight percentage: 1wt%-4wt% of additives, and the balance is high-purity quartz sand; the additives include the following components in weight parts: 0.6-1 parts of rare earth oxides, 2-3 parts of iron nitrate, 1-3 parts of manganese nitrate, 1-1.5 parts of cobalt nitrate, 0.1-0.3 parts of zinc nitrate, 0.05-0.08 parts of molybdenum nitrate, 0.05-0.1 parts of vanadium pentoxide, and 0.03-0.05 parts of hafnium oxide.

2. The black quartz boat according to claim 1, characterized in that, The welding adopts plasma arc welding + hydrogen-oxygen flame welding. During the welding process, the plasma arc provides a high-temperature heat source to melt the quartz material quickly, and the hydrogen-oxygen mixed gas provides a reducing atmosphere during the combustion process, effectively reducing oxidation and impurity residues at the weld.

3. The black quartz boat according to claim 1, characterized in that, The welding rod used in the welding comprises the following components in percentage by weight: 0.5-2% cerium oxide, 1-3% high-purity nano silicon powder, and the balance is silicon dioxide.

4. The black quartz boat according to claim 1, characterized in that, The average particle size of the high-purity quartz sand is 30-100 meshes.

5. The black quartz boat according to claim 1, wherein, The impurity content in the high-purity quartz sand is less than 10 ppm, and the silicon dioxide content is greater than 99.998 wt%.

6. The black quartz boat according to claim 3, wherein The average particle size of the high-purity nano silicon powder is 30-100 nm, and the purity is ≥99.9%; the particle size of the silicon dioxide is 100-200 mesh; and the particle size of the cerium oxide is 150-300 mesh.

7. The black quartz boat according to claim 1, characterized in that, The rare earth oxide is a mixture of neodymium oxide, yttrium oxide, lanthanum oxide and scandium oxide in a mass ratio of 1:(0.8-1.2):1:(0.2-0.4).

8. A production method of the black quartz boat according to any one of claims 1-7, characterized in that, The steps include: Step S1, production of black quartz plate and black quartz tube: rare earth oxide, vanadium pentoxide and hafnium oxide are added with acid to dissolve them to prepare an acidic solution; iron nitrate, manganese nitrate, cobalt nitrate, zinc nitrate and molybdenum nitrate are dissolved in water to prepare an aqueous solution; the above two solutions are mixed with high-purity quartz sand, and then heated to 1200°C in a sand baking machine for drying and expansion, and then screened and magnetically separated to remove metal impurities, and then put into a continuous melting furnace for smelting, respectively drawn into shape, and annealed to obtain black quartz plate and black quartz tube respectively; Step S2, welding: processing blind holes that have not been penetrated at the welding positions of the upper and lower black quartz plates to form a mechanical limit structure, then inserting the black quartz tube into the blind hole, and welding by plasma arc welding + oxyhydrogen flame welding; Step S3, post-processing: After welding is completed, the weld is ground and polished to make its surface smooth and flat.

9. The production method of the black quartz boat according to claim 8, characterized in that, The acid in step S1 is hydrochloric acid, and its mass percentage concentration is 36% to 38%; the mass ratio of the rare earth oxide to the acid is 1:(1-3); the mass ratio of the ferric nitrate to water is 1:(3-5); the smelting temperature in step S1 is 2100-2200° C., and the smelting time is 1-3h; the annealing temperature in step S1 is 550-650° C., and the holding time is 1-2h.

10. The production method of the black quartz boat according to claim 8, characterized in that, The plasma current of the plasma arc welding in step S2 is 100-120A, and argon gas protection is used; the hydrogen-oxygen mixed gas flow ratio of the oxyhydrogen flame welding is 1:1.5, and the welding speed is 8 mm / s.

Images