Sapphire Growing
1;Crucble
Every LED is born in a crucible.
In this crucible, aluminum oxide (Al2O3) is melted and structured into a
monocrystalline sapphire crystal. Depending on the method used, this process takes
between two and three weeks. The art of growing single crystals: The material is first
heated to over 2,000 degrees Celsius and is then allowed to cool slowly
in a controlled environment.
Only a few materials can be used to produce these crucibles.
This is because they must meet two requirements:
on the one hand, they must be resistant to the high
temperatures involved and, on the other, they must
not contaminate the melted sapphire. Sunstone’s
high-performance materials(W&Mo) are able
to meet precisely these requirements.
Furthermore, the crucible must be heated up by a
high-performance furnace which can generate the
high temperatures required and also be precisely
controlled andcooled. Here again, Sunstone’s expertise
in the materials and applications field comes to the fore. The heart of the melting
plant, the so-called hot zone, is designed to respond precisely to each customer’s
requirements before being constructed from high-performance materials. The thermal
process technicians of Sunstone’s production are closely working together to equip the
high-temperature furnaces required for the production of sapphire crystals worldwide
with furnace-making components.
Material Density Size Tungsten (99.95%) ≥18.3g/cc (sintered) Wall thickness: 0.02mm-50mm
Diameter:70-800mm
Height: 50-700mmMolybdenum (99.95%) ≥9.8g/cc (sintered) Wall thickness: 0.02mm-50mm
Diameter:70-550mm
Height: 50-700mmNOTE: Under vacuum or reducing atmosphere, the maximum operating temperature of tungsten crucibles is 2450℃, but 1700℃ for molybdenum crucible.
Tungsten heater
Tungsten heater components, as heat source in the sapphire growth furnace, have decisive effect for Al2O3 melt to form turbulence and produce radial temperature gradient. Therefore, high-purity and high-density tungsten heater components with delicate manufacture and reasonable design have great significance towards quality control ofsapphire crystal, energy saving and service life.
molybdenum sheet
After rolling and processing with deflection reaching 60% , the density of molybdenum sheet basically
comes close to molybdenum’s theory density. Therefore, molybdenum sheet possesses the properties of
high density, balanced internal structure and excellent high creep strength temperature. Molybdenum sheet
is widely used in reflection shield, cover plate applied in the sapphire growth furnace, reflection
shield, heating tape, connecting pieces applied in vacuum furnace
We provide super size moly sheet
0.3*600*2000mm
0.3*750*2000mm
Molybdenum reflection shield
As the heat-shield parts in the sapphire growth furnace, the most decisive function of molybdenum
reflection shield is to prevent and reflect the heat in the furnace. Heat-shield parts with high-density, exact-
measurement, smooth-surface, convenient-assembly and reasonable-design has great significance in
improving the crystal-pulling.
Upper and bottom cover plate
As the heat-shield parts in the sapphire growth furnace, the most decisive function of upper
and bottom cover plate is to prevent and reflect the heat in the furnace. Heat-shield parts
with high-density, exact-measurement, smooth-surface, convenient-assembly and
reasonable-design has great significance in improving the crystal-pulling
Tungsten rhenium wire
Alloying with rhenium improves the ductility of tungsten and reduces the ductile-to-brittle transition temperature.It
also increases the recrystallization temperatureand creep strength. WRe wire is used for bending in monocrystalline sapphire crystal under high-temperature
Standard Sizes for Tungsten-Rhenium Wire Item Diameter Content (mm) %Re %W W-25Re Wire 0.05-12.0 25 75 W-26Re Wire 0.05-12.0 26 74 W-5Re Wire 0.05-12.0 5 95 W-3Re Wire 0.05-12.0 3 97
W-25Re Wire is used for bending tungsten heater
Contact Us
Address: Shilog Development Zone,Mentougu District Beijing,China
Tel: 86-10-56945984
86-10-57462282
Fax: 86-10-57228751
skype:bjsunstone1
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