The key materials for melting optical glass and sapphire crystals
In today's high-tech industry, high-purity optical glass and sapphire crystals are the core materials used in the manufacturing of high-end lenses, lasers, semiconductors and smartphone screens. Their outstanding properties - unparalleled transparency, extremely high hardness and excellent thermal stability - are largely dependent on their nearly perfect manufacturing process. And in this process, a rare metal called "molybdenum" and its alloys play an indispensable and crucial role.
Why choose molybdenum? Outstanding performance meets extreme requirements
The reason why molybdenum is the preferred choice for melting these high-end materials lies in its unique physical and chemical properties, which perfectly match the demanding processing environment:
Extremely high melting point: The melting point of molybdenum is as high as 2620°C, which is much higher than the melting temperatures of optical glass (typically 1400-1600°C) and sapphire crystals (2050°C). This ensures the stability and integrity of the equipment's structure under long-term high-temperature conditions.
Excellent high-temperature strength: At high temperatures, molybdenum can still maintain extremely high strength and hardness, and is not prone to deformation or softening. This is crucial for components that require continuous stirring and must withstand the static pressure of the glass liquid or melt.
Outstanding anti-rust performance: Under long-term high-temperature and stress conditions, the molybdenum components have an extremely strong ability to resist slow plastic deformation, ensuring the continuity of production and the dimensional stability of the products.
Extremely low thermal expansion coefficient: The thermal expansion and contraction of molybdenum is very small, enabling it to withstand drastic temperature fluctuations without cracking, significantly extending the service life of the equipment.
Excellent thermal conductivity: Helps achieve uniform heat distribution during the melting process, reduces thermal stress, and thereby enhances the intrinsic quality and uniformity of the product.
Outstanding corrosion resistance: Molybdenum exhibits excellent chemical inertness towards many molten glasses and oxides, effectively resisting corrosion and preventing the introduction of impurities. It is a crucial guarantee for achieving high-purity products.
Core Application: How Molybdenum Products Empower High-End Manufacturing
In practical applications, molybdenum mainly serves the production lines of optical glass and sapphire crystals in three forms:
Stirring rod: The guardian of uniformity and purity
In the melting process of optical glass, eliminating bubbles and stripes (due to uneven refractive index) is a prerequisite for achieving high optical performance. The molybdenum rod processed molybdenum stirring rod is directly inserted into the molten glass at temperatures above 1500°C for continuous stirring. Its high strength ensures that it will not bend or deform in the viscous glass liquid, and its excellent corrosion resistance guarantees that it will not contaminate the glass body due to erosion， ultimately resulting in ultra-pure optical glass with highly uniform chemical composition and no defects.
2. Molybdenum crucible and molybdenum lining: The nurturing environment for pure growth
For the growth of sapphire crystals using processes such as the melt-growth method, the purity of the container directly determines the quality of the crystals. Molybdenum crucibles, molybdenum cups, or molybdenum alloy crucibles are ideal containers due to their high melting points and extremely low reactivity with the alumina melt. They provide a stable and clean "cradle" for the growth of sapphire crystals, ensuring the final production of large-sized, low-defect, and high-transparency sapphire ingots.
3. Electrode: Efficient and stable heat source core
In all-electric glass furnaces, molybdenum electrodes are the main heating elements. They are directly immersed in the molten glass and heated directly by electricity. This method has high thermal efficiency and precise temperature control. Molybdenum electrodes can work stably for a long time in the high-temperature and highly corrosive glass liquid, and they are the core technical guarantee for achieving energy conservation, high efficiency, and high-quality glass production.
Molybdenum Alloy: Further Enhancement of Performance
To further enhance the performance of pure molybdenum, such as improving the toughness after recrystallization and the resistance to sagging, molybdenum-lanthanum alloys are widely used. The added lanthanum oxide particles can anchor the grain boundaries, significantly increasing the material's high-temperature service life, enabling it to perform better in more demanding conditions, such as being used as more durable stirring rods or furnace components.
From the high-definition lenses of smartphone cameras, to the core windows of laser weapons, and to the substrates of LED lighting, high-purity optical glass and sapphire crystals are defining the clarity and reliability of modern technology. And behind this, molybdenum stirring rods, molybdenum crucibles and molybdenum electrodes, as the unsung heroes in the background, with their outstanding properties of high-temperature resistance, high strength and high purity, provide the most solid foundation for the birth of these advanced materials.
Molybdenum machining and fabricated products is in 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 and supply molybdenum electrode, molybdenum strip, molybdenum sheet, molybdenum pellet, molybdenum block, molybdenum tube, molybdenum rod, molybdenum wire, molybdenum processing workpiece according to customer demand.
