阅读说明：本技术 一种铱坩埚 (Iridium crucible ) 是由 孙岩 杨德江 于 2021-07-07 设计创作，主要内容包括：本发明属于坩埚加工技术领域,尤其是一种铱坩埚,包括铱坩埚本体,铱坩埚本体由铱板组成,铱板区分设置为埚底及埚壁；铱坩埚本体的埚壁设置有强化装置,强化装置对铱坩埚本体的埚壁进行改进,使其适用于高熔点晶体的生长,增加铱坩埚本体的使用寿命,强化装置包括有埚帮下端。该铱坩埚,通过设置强化装置,对铱坩埚本体的埚壁进行优化,从而在节约成本的前提下,铱坩埚装置的热应力不会因此而降低。在调节的过程中,通过采用等寿命原理,使用差异减薄的方式,对铱坩埚本体的埚帮上端进行积极减薄,但埚帮下端减薄较少,从而形成梯度,再对其进行焊接,从而实现了对铱坩埚在壁厚减薄过程中进行厚度优化,同时解决了生产成本。(The invention belongs to the technical field of crucible processing, and particularly relates to an iridium crucible which comprises an iridium crucible body, wherein the iridium crucible body is composed of an iridium plate, and the iridium plate is divided into a crucible bottom and a crucible wall; the crucible wall of iridium crucible body is provided with strengthens the device, strengthens the device and improves the crucible wall of iridium crucible body, makes its growth that is applicable to the high melting point crystal, increases the life of iridium crucible body, strengthens the device including the crucible group lower extreme. This iridium crucible through setting up the device of reinforceing, optimizes the crucible wall of iridium crucible body to under the prerequisite of practicing thrift the cost, iridium crucible device's thermal stress can not consequently and reduce. At the in-process of adjusting, through adopting the life-span principle such as, use the mode of difference attenuate, actively attenuate the crucible group upper end of iridium crucible body, but the thinning of crucible group lower extreme is less to form the gradient, weld it again, thereby realized carrying out thickness optimization to iridium crucible at the wall thickness attenuate in-process, solved manufacturing cost simultaneously.)

1. The utility model provides an iridium crucible, includes iridium crucible body (1), iridium crucible body (1) comprises at the bottom of crucible wall (3) and the crucible (2), its characterized in that: the thickness of the crucible wall (3) is gradually reduced from the contact part with the crucible bottom (2) to the crucible opening.

2. An iridium crucible as claimed in claim 1, wherein: the crucible bottom (2) and the crucible wall (3) have certain thicknesses as main structural structures, and can be set according to the size of a pulling crystal, wherein the diameter of the iridium crucible body (1) is 134mm, the height of the iridium crucible body is 130mm, and the thickness of the crucible bottom (2) is 2.5 +/-0.1 mm.

3. An iridium crucible as claimed in claim 1, wherein: the crucible bottom (2) and the crucible wall (3) are welded in an arc welding mode.

4. An iridium crucible as claimed in claim 1, wherein: the crucible wall (3) comprises a crucible side lower end (41) and a crucible side upper end (42), namely the crucible side lower end (41) is welded with the crucible bottom (2), the crucible side upper end (42) and the crucible side lower end (41) are designed in a differential thinning mode, namely the thickness of the crucible side lower end (41) is between the thickness of the crucible bottom (2) and the thickness of the crucible side upper end (42), the thickness value of the crucible side upper end (42) is 1.8mm, namely the thickness value of the crucible side lower end (41) is 1.8mm-2.5mm, and the crucible side upper end (42) is welded with the crucible side lower end (41).

5. An iridium crucible as claimed in claim 4, wherein: the thickness of the upper end (42) of the crucible edge, the lower end (41) of the crucible edge and the thickness of the crucible bottom (2) are symmetrical and uniform.

6. An iridium crucible as claimed in claim 1, wherein: the thickness of the central area of the crucible bottom (2) is larger than that of the edge area.

7. An iridium crucible as claimed in claim 6, wherein: the ratio of the diameter of the central area to the diameter of the crucible bottom (2) is 2/3-1/5.

8. A method of preparing the iridium crucible body of claim 1, comprising:

heating an iridium plate to be rolled to 1200-1600 ℃, and preserving heat for 2-60 min;

coating a layer of high-temperature-resistant sand on the surface of the iridium plate to be rolled, wherein the granularity of the high-temperature-resistant sand is 100-300 meshes;

feeding the iridium plate to be rolled into a rolling mill for rolling to obtain an intermediate iridium plate, wherein the thickness of the intermediate iridium plate is 150% -300% of the target thickness, and the target thickness is the thinnest thickness of the final iridium plate;

adjusting the thickness of a roller of the rolling mill to ensure that the thickness difference of two sides is 5-10%;

feeding the intermediate iridium plate into a rolling mill for continuous rolling until a final thick iridium plate is obtained;

rolling the iridium plate with the final thickness to obtain an iridium crucible wall (3);

and welding the thicker side of the iridium crucible wall (3) and the crucible bottom (2) in an arc welding mode to obtain the final iridium crucible body (1).

9. A method for preparing the anisotropic iridium crucible of claim 6, comprising:

heating an iridium plate to be rolled to 1200-1600 ℃, and preserving heat for 2-60 min;

coating a layer of high-temperature-resistant sand on the surface of the iridium plate to be rolled, wherein the granularity of the high-temperature-resistant sand is 100-300 meshes;

feeding the iridium plate to be rolled into a rolling mill for rolling to obtain an intermediate iridium plate, wherein the thickness of the intermediate iridium plate is 150% -300% of the target thickness, and the target thickness is the thinnest thickness of the final iridium plate;

adjusting the thickness of a roller of the rolling mill to ensure that the thickness difference of two sides is 5-10%;

feeding the intermediate iridium plate into a rolling mill for continuous rolling until a final thick iridium plate is obtained;

rolling the iridium plate with the final thickness to obtain an iridium crucible wall (3);

cutting to obtain an iridium wafer with a uniform crucible bottom (2) corresponding to the crucible wall (3);

cutting to obtain a thickened support corresponding to the iridium wafer at the crucible bottom (2), wherein the ratio of the diameter of the thickened support to the diameter of the crucible bottom (2) is 2/3-1/5;

welding the thickening support to the central area of the crucible bottom (2) in an arc welding mode to form the crucible bottom (2) with uneven thickness;

and welding the thicker side of the iridium crucible wall (3) and the crucible bottom (2) in an arc welding mode to obtain the final iridium crucible body (1).

10. The shaped iridium crucible as recited in claim 1, wherein: the crystal growth of the iridium crucible body (1) comprises a pulling method device (5), wherein the pulling method device (5) is provided with the iridium crucible body (1), a pulling rod (51), a seed crystal (52) and a heating system (53).

Technical Field

The invention relates to the technical field of crucible processing, in particular to an iridium crucible.

Background

The iridium crucible uses noble metal iridium as a raw material, and the iridium value is high, so that the wall thickness of the iridium crucible is continuously reduced in recent years, and the wall thickness of the iridium crucible is only 60% of the initial design value after the continuous reduction of the wall thickness for many years, and the thermal load of the crucible is not changed.

Due to the requirement of temperature control, the lower end of the crucible wall is a highest temperature region, and the temperature is about 100-150 ℃ higher than that of the upper end of the crucible wall. When growing an intraocular lens with a higher melting point, such as LYSO with a melting point of 2150 deg.C, the temperature at the bottom of the crucible side is very close to the melting point of iridium, as shown in FIG. 3.

The iridium crucible is placed in a medium frequency inductor and generates heat due to the induced eddy current. Under the influence of skin effect, the current is concentrated on the outer side of the crucible, and certain wall thickness is needed for heat conduction and homogenization. When the wall thickness is too thin, the heat-homogenizing function is weakened, and when the wall thickness approaches the limit, the region is easily damaged early, resulting in a reduction in the service life of the crucible.

On the other hand, in the process of preparing the crystal, when a crystal pulling cycle is completed, the processes of cooling, feeding and re-heating are often required, in the process, crystal raw materials are always remained at the bottom of the crucible, and the crystal raw materials have different densities in a solid state and a liquid state, so that the crucible is deformed once, and when the service cycle of the crucible is longer, the effect is more obvious, as shown in fig. 4, the crucible is easy to crack from the bottom due to the continuous deformation, and the leakage accident is caused. On the other hand, because the crystal is required to rotate in the crystal growth process, the molten raw material in the crucible rotates along with the crystal, and when the temperature is low or the crucible is used for a long time, the bottom of the crucible can be screwed, so that the service life of the crucible is shortened.

Disclosure of Invention

Based on the technical problem that the service life of the existing iridium crucible is short, the invention provides an iridium crucible.

The iridium crucible provided by the invention comprises an iridium crucible body, wherein the iridium crucible body consists of a crucible bottom and a crucible wall;

the iridium raw material used by the iridium crucible body meets the requirement that the purity of iridium powder in GB/T1422 is not lower than SM-Ir99.95 mark.

Preferably, the crucible bottom and the crucible wall are used as main structural structures and have certain thickness, and the thickness can be set according to the size of a pulling crystal, wherein the iridium crucible body has the diameter of 134mm and the height of 130mm, and the thickness of the crucible bottom is 2.5 +/-0.1 mm;

preferably, the crucible bottom and the crucible wall are welded in an arc welding mode;

preferably, the crucible wall comprises a crucible side lower end and a crucible side upper end, namely the crucible side lower end is welded with the crucible bottom, the crucible side upper end and the crucible side lower end are designed in a differential thinning mode, namely the thickness of the crucible side lower end is between the thickness of the crucible bottom and the thickness of the crucible side upper end, the thickness value of the crucible side upper end is 1.8mm, namely the thickness value of the crucible side lower end is 1.8mm-2.5mm, and the crucible side upper end is welded with the crucible side lower end;

through the technical scheme, because temperature control's needs, the crucible group lower extreme of iridium crucible body crucible wall is the highest region of temperature, about 100 ~ 150 degrees than the temperature of crucible group upper end, so adopt equal life theory to crucible group upper end and crucible group lower extreme, positive attenuate promptly to crucible group upper end, but the lower part attenuate of crucible group is less, thereby form the gradient, but the thickness value of crucible group lower extreme is between crucible end and crucible group upper end, so thickness between the three is close, can match and weld, the welding method of gradient formula can strengthen the thermal stress of iridium crucible body inner wall, eliminate the local penetration of iridium crucible body, and because iridium is worth expensive, but the crucible wall welding method of gradient formula can greatly reduced manufacturing cost, resources are saved.

Preferably, the thicknesses of the upper end of the crucible wall, the lower end of the crucible wall and the crucible bottom are symmetrical and uniform;

preferably, the upper end of the crucible wall, the lower end of the crucible wall and the inner surface of the crucible bottom are flat and smooth;

preferably, the crystal grown by the iridium crucible body comprises a pulling method device, and the pulling method device is provided with the iridium crucible body, a pulling rod, a seed crystal and a heating system;

the beneficial effects of the invention are as follows:

through setting up the device of reinforceing, optimize the crucible wall of iridium crucible body to under the prerequisite of practicing thrift the cost, the thermal stress of iridium crucible device can not consequently and reduce. At the in-process of adjusting, through adopting the equal life principle, use the mode of difference attenuate, the crucible of iridium crucible body helps the upper end to carry out positive attenuate, and helps the lower extreme to the crucible and thicken the processing to form the gradient, weld at the bottom of it and the crucible, thereby realized carrying out thickness optimization to iridium crucible at the wall thickness attenuate in-process, thereby improved the life of crucible.

Drawings

FIG. 1 is a schematic view of a conventional iridium crucible for crystal growth;

FIG. 2 is a schematic view of a special-shaped iridium crucible according to the present invention;

FIG. 3 is a front view of the pulling method device for a special-shaped iridium crucible according to the present invention.

FIG. 4 is a schematic diagram of a bottom structure of an iridium hetero-crucible provided by the invention.

FIG. 5 is a photograph of the crucible wall after 6 cycles of use of the iridium crucible of the present application;

FIG. 6 is a photograph of the crucible wall after a conventional iridium crucible has been used for 6 cycles;

FIG. 7 is a photograph of the bottom of the thickened iridium crucible of the present application after being used for 6 cycles;

FIG. 8 is a bottom plan view of a conventional iridium crucible after 6 cycles of use;

FIG. 9 is a bottom view of a conventional iridium crucible after 6 cycles.

In the figure: 1. an iridium crucible body; 2. a crucible bottom; 3. a crucible wall; 4. a strengthening device; 41. the lower end of the crucible side; 42. the upper end of the crucible side; 5. a Czochralski device; 51. lifting a pull rod; 52. seed crystal; 53. a heating system.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

Referring to fig. 1-9, an iridium crucible comprises an iridium crucible body 1, wherein the iridium crucible body 1 is composed of an iridium plate, and the iridium plate is divided into a crucible bottom 2 and a crucible wall 3;

the iridium raw material used by the iridium plate meets the requirement that the purity of iridium powder in GB/T1422 is not lower than SM-Ir99.95 mark, the crucible wall 3 of the iridium crucible body 1 is provided with the strengthening device 4, the strengthening device 4 improves the crucible wall 3 of the iridium crucible body 1, so that the iridium crucible is suitable for the growth of high-melting-point crystals, the service life of the iridium crucible body 1 is prolonged, and the strengthening device 4 comprises a crucible side lower end 41;

the crucible bottom 2 and the crucible wall 3 have certain thickness as main structural structures, and can be set according to the size of a crystal, wherein the diameter of the iridium crucible body 1 is 134mm, the height of the iridium crucible body is 130mm, the thickness of the crucible bottom 2 is 2.5 +/-0.1 mm, the crucible bottom 2 and the crucible wall 3 are welded, specifically, the rolling welding is adopted, and the rolling welding has the characteristics of flat and smooth surface, compact internal structure, uniform wall thickness, suitability for a symmetrical temperature field required by crystal growth, and capability of processing large-size, special-shaped and thin-wall iridium crucibles;

the crucible wall 3 comprises a lower end 41 of a crucible edge and an upper end 42 of the crucible edge, namely the lower end 41 of the crucible edge is welded with the crucible bottom 2, the upper end 42 of the crucible edge and the lower end 41 of the crucible edge are designed in a mode of differential thinning, namely the thickness of the lower end 41 of the crucible edge is between the thicknesses of the crucible bottom 2 and the upper end 42 of the crucible edge, the thickness value of the upper end 42 of the crucible edge is 1.8mm, namely the thickness value of the lower end 41 of the crucible edge is 1.8mm-2.5mm, the upper end 42 of the crucible edge is welded with the lower end 41 of the crucible edge, because of the requirement of temperature control, the lower end 41 of the crucible edge 3 of the iridium crucible body 1 is a region with the highest temperature, which is about 100-150 degrees higher than the temperature of the upper end 42 of the crucible edge, the upper end 42 of the crucible edge and the lower end 41 of the crucible edge adopt the same concept of service life, namely, the upper end 42 of the crucible edge is actively thinned, but the lower portion of the crucible edge is less, so that the thickness of the lower end 41 of the crucible edge is close to the thickness of the crucible edge, and the thickness of the crucible edge is between the lower end 41 of the crucible edge and the crucible edge of the crucible edge and the thickness of the crucible edge is close to the thickness of the crucible edge, the welding can be carried out in a matching way, the gradient type welding mode can enhance the thermal stress of the inner wall of the iridium crucible body 1, eliminate the local penetration of the iridium crucible body 1, and the gradient type crucible wall 3 welding mode can greatly reduce the production cost and save resources because the iridium value is high;

the thickness of the upper end 42 of the crucible edge, the thickness of the lower end 41 of the crucible edge and the thickness of the crucible bottom 2 are symmetrical and uniform, and the inner surfaces of the upper end 42 of the crucible edge, the thickness of the lower end 41 of the crucible edge and the thickness of the crucible bottom 2 are flat and smooth;

referring to fig. 4, the invention further provides a hetero iridium crucible, which comprises an iridium crucible body 1, wherein the iridium crucible body 1 is composed of an iridium plate, the iridium plate is divided into a crucible bottom 2 and a crucible wall 3, and the crucible bottom 2 comprises a thickening support 4.

But the thickening holds in the palm 4 thickness can be the same with plate thickness at the bottom of the crucible, also can be different, for example, when thickness is 2mm at the bottom of the crucible, the thickening holds in the palm and can make 3mm, also can be 1mm, and like this through the regional welding thickening back of holding in the palm at the bottom of the crucible, the regional thickness at the bottom of the crucible can be 5mm or 3 mm.

The diameter of the crucible bottom thickening support can be 2/3-1/5 of the diameter of the crucible bottom, and can be determined by calculation according to the acting force on the crucible bottom in the crystal growth process.

The method for preparing the crucible body according to the embodiments of the present application will be described with reference to the following specific examples. It should be understood that this particular method is merely illustrative of the method for preparing the crucible of the present application and should not constitute any limitation on the core technology of the present application.

The method for preparing the crucible body of the embodiment specifically comprises the following steps:

the first step is as follows: heating an iridium plate to be rolled to 1200-1600 ℃, and preserving heat for 2-60 min;

the iridium metal is brittle at low temperature and difficult to process by deformation, and the inventor finds that the iridium metal has better thermal deformation capacity at 1200-1600 ℃, so that when the iridium plate to be rolled is subjected to deformation treatment, the temperature is heated in the temperature interval and is kept for a certain time, so that the iridium plate has better deformation capacity conveniently.

The second step is that: coating a layer of high-temperature-resistant sand on the surface of the iridium plate to be rolled, wherein the granularity of the high-temperature-resistant sand is 100-300 meshes;

the inventors have found that the service life of an iridium crucible can be significantly improved when the crucible is shown to have a rugged structure, and the detailed description of the specific principles is provided in the patent content previously disclosed by the applicant, and the patent application No. 201810201103.2, which is not described in detail herein.

The third step: and feeding the iridium plate to be rolled into a rolling mill for rolling to obtain an intermediate iridium plate, wherein the thickness of the intermediate iridium plate is 150-300% of the target thickness, and the target thickness is the thinnest thickness of the final iridium plate.

When the iridium plate to be rolled is rolled, the iridium plate to be rolled is usually deformed by adopting a large deformation amount at the beginning of rolling, the deformation amount of each pass is large, the microstructure of the iridium plate is easy to be refined, crystal grains of the iridium plate are fine, but the large deformation amount is difficult to accurately control the size of the final iridium plate subsequently, so when the iridium plate is rolled to 150-300% of the target thickness, the deformation amount is switched, and the iridium plate with the target thickness is rolled by adopting a small deformation amount and multiple passes for slow deformation.

The fourth step: adjusting the thickness of a roller of the rolling mill to ensure that the thickness difference of two sides is 5-10%;

in this step, the thickness difference is generated in the roll axial direction in the iridium sheet rolled in each pass by making the thicknesses of both sides of the roll different.

The fifth step: feeding the intermediate iridium plate into a rolling mill for continuous rolling until a final thick iridium plate is obtained;

and a sixth step: rolling the iridium plate with the final thickness to obtain a crucible wall of the crucible;

the seventh step: and welding the thicker side of the crucible wall of the crucible and the crucible bottom in an arc welding mode to obtain the final crucible body.

It should be understood that the anisotropic iridium crucible of the invention can also be used for thickening the crucible bottom. The corresponding preparation process may thus further comprise:

and cutting the crucible bottom iridium wafer with uniform thickness corresponding to the opposite crucible wall.

In the iridium crucible processing process, the crucible wall and the crucible bottom are often connected together in a welding mode to form the iridium crucible body. The iridium wafer at the bottom of the crucible can be obtained by cutting in a linear cutting mode and also can be obtained by a laser cutting mode, and the method is not limited in the application.

And cutting the thickened support corresponding to the crucible bottom.

In this application, the thickness that the thickening held in the palm at the bottom of the crucible can be the same with plate thickness at the bottom of the crucible, also can be different, for example, when thickness was 2mm at the bottom of the crucible, the thickening held in the palm can make 3mm, also can be 1mm, holds in the palm the back through the regional welding thickening at the bottom of the crucible, and the regional thickness at the bottom of the crucible can be 5mm or 3mm like this.

And welding the thickening support in the central area of the crucible bottom in a welding mode.

In this application, the diameter of crucible end thickening support can be between 2/3 ~ 1/5 of crucible end diameter, specifically can calculate according to the effort to the crucible end in the crystal growth process and confirm.

And welding the crucible bottom with the thickened support and the opposite crucible edge together to obtain the crucible body.

It should be understood here that when the thick holds in the palm the crucible end and welds with different sex iridium crucible pot rim, the thick holds in the palm can be inside towards the crucible, also can be outside towards the crucible, specifically confirms according to the crystal growth demand, to this, and this application is not injectd.

It should also be understood that the anisotropic iridium crucible provided by the application can be welded with a crucible side with uniform thickness at the bottom of the thickened support, so that the iridium crucible with the thickened support at the bottom of the crucible is formed.

The crystal growth of the iridium crucible body 1 comprises a pulling method device 5, and the pulling method device 5 is provided with the iridium crucible body 1, a pulling rod 51, a seed crystal 52 and a heating system 53;

through setting up the device 4 of reinforceing, optimize the crucible wall 3 of iridium crucible body 1 to under the prerequisite of practicing thrift the cost, the thermal stress of iridium crucible device can not consequently and reduce. At the in-process of adjusting, through adopting the equal life principle, use the mode of difference attenuate, actively attenuate the crucible group upper end 42 of iridium crucible body 1, but the crucible group lower extreme 41 attenuate is less to form the gradient, weld it again, thereby realized carrying out thickness optimization to iridium crucible at the wall thickness attenuate in-process, solved manufacturing cost simultaneously.

The working principle is as follows: the invention utilizes a pulling method to grow raw material crystals, namely, the raw material of the crystal to be grown is firstly put in a high-temperature-resistant crucible body 1 for heating and melting, the temperature field in the furnace is adjusted, the upper part of the melt is in a supercooled state, then a seed crystal 52 is arranged on a pulling rod 51, the seed crystal 52 is contacted with the surface of the melt, after the surface of the seed crystal 52 is slightly melted, the pulling rod 51 is pulled and rotated, the melt is in the supercooled state and is crystallized on the seed crystal 52, and cylindrical crystals grow in the continuous pulling and rotating processes;

when an artificial crystal with a higher melting point is grown, if the melting point of LYSO is 2150 ℃, the temperature of the bottom of the crucible side of the iridium crucible body 1 is very close to the melting point of iridium, and the wall thickness is too thin, the heat homogenizing function is weakened, and when the wall thickness is close to the limit, the crystal close to the melting point of iridium, such as LYSO, can be directly expressed as local fusion, so that the crucible wall 3 for welding the upper end 42 of the crucible side and the lower end 41 of the crucible side with the gradient thickness has good thermal stress.

The effect of the iridium plate of the embodiment of the present application in practical use is described in detail below. FIG. 4 is a photograph of an iridium crucible processed from an iridium plate produced by the claimed method after being used for 6 cycles, and FIG. 5 is a photograph of two iridium crucibles processed by a conventional method after being used for 5 cycles. The three iridium crucibles were all subjected to the production of YAG (yttrium aluminum garnet) crystals in the same artificial crystal growth furnace at a production temperature of about 1960 ℃ for a single crystal production period of about 28 days. Two iridium crucibles prepared by the conventional method both leaked after 5 cycles of use, and the crucibles were found to be cracked after the machine check. The iridium crucible prepared by the method of the present application did not crack after 6 cycles of use. Practical use proves that the iridium crucible prepared by the method has stronger anti-deformation capability at the bottom of the crucible side, and the service life of the crucible is obviously improved.

FIG. 6 is a photograph of the bottom of an iridium crucible prepared by the method of the example of the present application after 6 cycles of use. Fig. 7 and 8 are photographs of the inside and outside of the bottom of a conventional iridium crucible after 6 cycles of use. It can be seen from the photograph that the bottom-twisting effect of the crucible with the thickened support is significantly reduced, and the crucible is prevented from deforming and damaging in the long-time use process.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.