Materials for an efficient heat insulation barrier
In cutting-edge fields such as materials science, aerospace, and semiconductor manufacturing, high-temperature processing techniques often require to be carried out in an extremely hot environment close to 2000℃. These processes have extremely strict requirements for the stability and cleanliness of the thermal environment. And the core component that undertakes the tasks of insulation and anti-pollution is a multi-layer insulation system constructed from molybdenum sheets.
I. Thermal Insulation Challenges in High-Temperature Environments
In high-temperature furnaces, heat is mainly dissipated through radiation. The rate of radiation heat transfer is proportional to the fourth power of the temperature. When the furnace temperature exceeds 1500℃, the heat loss increases sharply, not only resulting in significant energy consumption but also posing extreme challenges to the performance of thermal insulation materials.
Furthermore, the volatilization of materials under high-temperature conditions will contaminate the atmosphere inside the furnace, affecting the quality of the workpieces - whether it is the purity of semiconductor ingots or the performance of aerospace alloys, they may all be damaged as a result. Therefore, an ideal heat-insulating material must possess three key characteristics: high temperature resistance, low volatility, and structural stability.
II. Molybdenum Discs: The Ideal Choice for High-Temperature Insulation
Among various metal materials, molybdenum stands out and becomes the key material for the heat insulation system of the high-temperature furnace, mainly due to the following characteristics:
High melting point: The melting point of molybdenum is as high as 2622℃, enabling it to maintain its structural integrity and prevent softening or deformation even in a working environment of 1800–2000℃.
Low vapor pressure: In a high-temperature and vacuum environment, the evaporation rate of molybdenum is extremely low, effectively preventing it from becoming a source of pollution.
Excellent radiation reflection capability: The smooth surface of the molybdenum circular plate can efficiently reflect infrared radiation, reducing heat absorption.
III. Working Principle of the Multi-layer Molybdenum Plate Insulation System
The insulation barrier composed of multiple layers of parallel-matched molybdenum plates does not merely achieve insulation through the thickness of the material; instead, it achieves efficient thermal resistance through the "reflection-decay" mechanism:
Radiation reflection: When the heat radiation emitted by the furnace core strikes the innermost molybdenum plate, most of it is reflected back to the heat source.
Layer-by-layer attenuation: A small amount of absorbed heat causes the molybdenum sheet to heat up and radiate outward, but each layer significantly reduces the radiation intensity.
Thermal resistance addition: The multi-layer structure significantly extends the thermal conduction path, forming an efficient thermal resistance layer, which greatly reduces heat loss.
This design not only enhances the thermal efficiency but also reduces the load of the cooling system, while forming a physical pollution barrier to prevent the cross-migration of volatile substances between the inside and outside.
IV. Typical Application Scenarios
The molybdenum sheet insulation system plays an irreplaceable role in the following high-temperature processes:
Vacuum sintering furnace: Used for sintering of hard alloys and high-purity ceramics, ensuring uniform temperature and pure atmosphere;
Crystal growth furnace: Provides a stable and clean high-temperature environment during the growth of sapphire and silicon single crystals;
Aerospace alloy heat treatment: Ensure that critical components such as turbine blades undergo heat treatment in a pollution-free environment;
High-purity graphitization furnace: During the process of graphite purification, it can withstand extremely high temperatures and maintain structural stability.
The multi-layer heat insulation system constructed by molybdenum sheets is a fundamental and crucial technology in modern ultra-high-temperature industrial equipment. It not only significantly improves the efficiency of heat utilization, but also ensures the high cleanliness and stability of the high-temperature process environment, becoming the silent guardian behind the perfect birth of numerous cutting-edge materials in the "high-temperature furnace".
The molybdenum disc is in high demand in various parts of the world, such as: USA, Canada, Chile, Brazil, Argentina, Colombia, Germany, France, United Kingdom, Italy, Sweden, Austria, Netherlands, Belgium, Switzerland, Spain, Czech Republic, Poland.
Mosten Alloy can produce molybdenum crucible, molybdenum tube, molybdenum sheet, molybdenum pellet, molybdenum block, molybdenum foil, molybdenum rod, molybdenum wire, molybdenum processing workpiece according to customer demand.
