A kind of sapphire crystallization furnace energy saver
Technical field
The invention belongs to sapphire crystallization furnace technical field, be specifically related to a kind of sapphire crystallization furnace energy saver.
Background technology
Sapphire crystal is owing to having high strength, high rigidity, a series of excellent comprehensive physical and chemical performances such as high temperature resistant, abrasion-resistant, chemical stability are good, being the epitaxially grown commercialization substrate material of GaN base LED, accounting for market 95%, is the base mateiral of semiconductor illumination technique and industry.
The fusing point of sapphire crystal is up to 2050 DEG C, grow extremely difficult, the sapphire crystal of more than diameter 200mm mainly contains kyropoulos and heat-exchanging method, heat-exchanging method is the unique method of the sapphire crystal of at present stable growth overall dimension and most high optical quality in the world, it independently can to control in crystal thermograde in thermograde and melt, is conducive to growing high-quality, large-sized sapphire crystal.At present can volume production 100 kilograms of sapphire optical crystal.
The brilliant stove of length that heat-exchanging method uses is exactly load onto the heat exchanger that a tungsten makes in the bottom of vacuum graphite resistance furnace, cooling helium is inside had to flow through, the crucible that raw material is housed is placed on the top of heat exchanger, both overlap at center, and seed crystal is placed in the center of crucible bottom, after the raw material in crucible is by heat fused, now, because helium flow is through heat exchanger cooling, seed crystal is not melted, after helium gas flow strengthens gradually, then from the heat also corresponding increase that melt is taken away, seed crystal is grown up gradually, the melt in whole crucible is finally made all to solidify.
The heat-exchanging method production sapphire crystal cycle is very long, and more than 15 days, required heating power was very high, and its long brilliant feature determines long brilliant stove and be all in the condition of high temperature in for a long time.As shown in Figure 1, long brilliant stove well heater is connected with three electrodes prior art sapphire crystallization furnace structure, and three electrode places exist three holes, can produce heat leakage.
The leakage of this place's heat has following problem:
1) burner hearth can be caused to weld weakness occur leaking even crack, minor amount of water flash evapn in 2000 degree of brilliant stoves of length of leakage becomes gaseous state, causes furnace pressure to rise fast, and long brilliant process is out of control, and may cause work safety accident.
2) leakage of heat is exactly the waste of heat energy, can increase the heating power in sapphire production process, and the more energy consumption of each growth needs, is unfavorable for energy saving standard.
3) leakage of heat can reduce the space in the temperature field in well heater or crucible, and temperature field limits more greatly, the production of higher crystal, also can reduce the internal soundness of the sapphire crystal produced at present.
Summary of the invention
The present invention is according to the deficiencies in the prior art, provide a kind of assembled energy-saving device, be arranged on three electrodes of sapphire crystallization furnace, both can weld weak location to burner hearth and carry out thermal protection, the energy waste that thermal radiation produces can be reduced again, improving the inner quality of sapphire crystal, improving basic substance for producing larger sized sapphire crystal.
Concrete technical scheme of the present invention is:
A kind of sapphire crystallization furnace energy saver; it is characterized in that this energy saver comprises an assembly type corundum ceramic back-up ring be arranged between electrode protection cover and furnace wall; this back-up ring cross section is L-shaped; comprise external diameter and be greater than the annular gear edge that furnace wall electrode hole and internal diameter be greater than electrode external diameter, overlap consistent cylinder base with an internal diameter with electrode protection.Optimally, described energy saver also comprises second back-up ring be located between electric motor protecting cover and graphite casing.
Optimally, described assembly type back-up ring is put together by two semicircles are scarce.
Optimally, the gear of described back-up ring is provided with one for being socketed the circular groove of electrode protective sleeve along surface.
Optimally, described semicircle lacks by buckle structure connected.
Optimally, described gear is curved along bottom.
Cylinder base can be arranged to certain tapering, matches with burner hearth, and this is conducive to annulus and burner hearth close contact.
The heat conduction efficiency of corundum ceramic is lower; protection effectively can be blocked to burner hearth three electrode welding weakness in ceramic ring lateral part; the actual temperature of effective reduction electrode commissure; the stress avoiding weld seam to produce because of thermal radiation causes cracking; simultaneously also can space to a certain extent between enclosed-electrode graphite protective sleeve; prevent heat leak, thus improve the thermo-efficiency of thermal field.
Pottery back-up ring adopts high-quality corundum to fire and forms, purity 95%-99%, and can bear the high temperature of more than 1700 degree and indeformable for a long time, the chemical composition of corundum is identical with sapphire simultaneously, thus avoids in the burner hearth of impurity introducing, affects the quality of crystal.
Because the mounting condition of sapphire crystallization furnace limit, cannot make back-up ring and graphite protective sleeve one-body molded, therefore, this programme is the optimal selection under prior art condition.
Accompanying drawing explanation
Fig. 1 is prior art sapphire crystallization furnace structural representation.
Fig. 2 is the sapphire crystallization furnace structural representation containing the present invention's pottery back-up ring.
Fig. 3 is the present invention's pottery back-up ring plan structure schematic diagram.
Fig. 4 is the present invention's pottery back-up ring sectional structure schematic diagram.
Fig. 5 is the sapphire crystallization furnace structural representation containing the present invention's two ceramic back-up rings.
Fig. 6 is arced ceramic back-up ring sectional structure schematic diagram of the present invention.
Fig. 7 is the present invention's pottery back-up ring male and female split structural representation.
Fig. 8 is the present invention's pottery back-up ring step split structural representation.
Wherein, electrode 1, furnace wall 2, graphite casing 3; well heater 4, electrode protection cover 5, gap 6, back-up ring 7; second back-up ring 8, electrode protection cover 9, circular groove 10, the first semicircle lacks 71; second semicircle lacks 72, projection 710, and base 711, keeps off along 712; plane 713, projection 714, groove 720; groove 724, base 82, cambered surface 81.
Embodiment
Below in conjunction with accompanying drawing, the present invention will be further described.
As shown in figs 2-4; energy saver comprises an assembly type corundum ceramic back-up ring 7 be arranged between electrode protection cover 9 and furnace wall 2; this back-up ring 7 cross section is L-shaped; comprise external diameter to be greater than furnace wall electrode hole and internal diameter and to be greater than the annular gear of electrode external diameter along 712, overlap consistent cylinder base 711 with an internal diameter and electrode protection.
As shown in Figure 5, this energy saver also can comprise second back-up ring 8 be located between electric motor protecting cover and graphite casing.
As shown in Figure 3, assembly type back-up ring 7 lacks 72 by semicircle scarce 71 and semicircle and is put together, and the gear of back-up ring 7 is provided with one for being socketed the circular groove 10 of electrode protective sleeve 9 along 712 surfaces.
Described semicircle lack 71 and semicircle lack and 72 to be connected by buckle structure, concrete structure can two kinds of heteroid buckles as shown in Figure 7 and Figure 8.
Optimally, described gear can curved 81 along bottom, the burner hearth 2 of circular arc of fitting better and graphite casing 3.