Tungsten and molybdenum products for sapphire crystal growth furnaces are mainly produced from tungsten raw materials and molybdenum raw materials with purity higher than 99.95%, including tungsten crucible, tungsten plate, tungsten sheet, tungsten wire, tungsten electrode screen, tungsten cylinder, tungsten separator Heat screen, molybdenum crucible, molybdenum heat shield, molybdenum heating element, molybdenum thermal field, molybdenum support frame and molybdenum electrode screen, etc. Thanks to tungsten, which has the highest melting point among all metals, tungsten crucibles are widely used in the growth of sapphire single crystals.

Using a tungsten crucible as the carrier of a sapphire single crystal growth furnace rarely uses the tungsten crucible itself as a heating element, and tungsten atoms will volatilize at high temperatures. It is also possible to use the tungsten crucible itself as the heating element, but the selection of the process and the setting of the working environment temperature are very critical factors. Due to differences in the preparation process of tungsten crucibles, domestic sapphire single crystal growth furnaces generally use press-sintered tungsten crucibles. 

 
 
The advantage of tungsten crucible for the growth of sapphire single crystal is that the decrystallization stage during the growth of sapphire single crystal often causes sticking phenomenon. However, the tungsten in the tungsten crucible is a high-temperature resistant refractory metal and does not easily react with sapphire. It can well protect the purity of sapphire. The sapphire single crystal made by the bubble method requires a better temperature field device. The spinning type tungsten crucible is of high quality and has relatively high purity and density, but the price is also high.
The disadvantage of tungsten crucible for sapphire single crystal growth is that the tungsten crucible cannot be placed on a cold metal table immediately after heating, otherwise it will crack. The thickness of most tungsten crucibles is relatively thin, which is not conducive to long-term use and performs poorly in terms of the number of reuses. This will increase the cost of sapphire single crystal growth.

Therefore, when selecting a tungsten crucible for sapphire single crystal growth, the appropriate type of tungsten crucible must be selected based on the single crystal preparation process and the conditions of the single crystal growth furnace.