|
[China]
Trade Verify
Address: No.188 Gaoxin Road,Weibin District Baoji City,Shaanxi,China
Contact name:Nicole
Shaanxi Peakrise Metal Co.,Ltd |
|
Verified Suppliers
|
|
|
Furnace For Sapphire Crystal Growth With A Molybdenum Thermal Field
1. An explanation of the molybdenum thermal field used in the
furnace to grow sapphire crystals:
Parts of vacuum furnaces can also be insulated using graphite and
molybdenum metal. The heat shield in an all-metal thermal field is
made up of several layers of metal plates, with a specific amount
of space between each layer.
In a standard vacuum furnace with a working temperature of 1315°C,
the heat shield is usually composed of two layers of molybdenum
sheets on the inside and three layers of stainless steel sheets on
the outside.The quantity of molybdenum sheets and the thickness of
each layer must be increased if greater operating temperatures are
necessary. Molybdenum sheet can be substituted with tantalum sheet
if the operating temperature is higher than 1650 °C. The number of
layers and the distance between the metal sheets determine the
thermal insulation performance for an all-metal thermal field.
These distances are utilized to stop heat from conducting and
radiating outside the thermal field's core. The thermal radiation
released from the thermal field's center is reflected back to the
workpiece there as a result of the molybdenum sheet's reflecting
qualities. In locations where there is a need for extreme
cleanliness and vacuum, all-metal thermal fields are frequently
used. It should be noted that for the all-metal thermal field,
embrittlement of the molybdenum metal will occur at 1150°C due to
the metal's recrystallization, and the embrittled metal heat shield
is easily damaged by the fixture or workpiece that falls on the
screen. The cost of all-metal thermal fields is frequently more
expensive than those built of other materials due to the high cost
of molybdenum metal.
2. Molybdenum Thermal Field For Sapphire Crystal Growth Furnace
Measurements and Tolerances:
Unit:mm
| produced with a single sheet of molybdenum | produced by a sheet of several molybdenum | ||
| thickness | Max cylinder diameter | Max cylinder height | |
| 2.0±0.1 | 450±2 | 660±1 | |
| 1.0±0.08 | 610±2 | 660±1 | Manufacture according to customers’ |
| 0.5±0.04 | 700±2 | 660±1 | requirements |
| 0.3±0.03 | 700±2 | 660±1 | |
According to the needs of the customer, special sizes can be produced.
3. The Molybdenum Thermal Field For Sapphire Crystal Growth Furnace's manufacturing procedure and apparatus:
| Item | Process | Equipment | Quality check point |
| 1 | Mo sheet | 1 Physical and chemical properties 2 Measurements (length ,width) | |
| 2 | Check | 3 Surface quality | |
| 3 | Wound roll | Rotary machine | 1 Surface clearness |
| 4 | Check | 2 Diameter and height of cylinder | |
| 5 | Drilling, rivet | Drill press | 1 Rivet secure |
| 6 | Clean | Riveting machine | 2 Location of assembling hole |
| 7 | Check | ||
| 8 | Assembly | Assembly platform | 1 Surface clearness |
| 9 | Clean | 2 The diameter and height of cylinder conforming to the | |
| 10 | Check | requirements | |
| 11 | Package | 3 Solid assembly, and no splice among layers 4 Show certificate of quality |
4. Utilization of a Molybdenum Thermal Field in a Furnace for
Growing Sapphire Crystals:
The most important role of the molybdenum reflection shield is to
prevent and reflect the heat in the sapphire growing furnace as one
of the heat-shielding components. Enhancing the crystal-pulling
requires heat-shield components with high density, precise
measurement, smooth surface, easy assembly, and acceptable design.
Vacuum furnaces, etc., can also use molybdenum thermal fields to
heat insulation and reflect heat.
