The processing and manufacturing technology of pure molybdenum wire
Pure molybdenum wire features a high melting point (2610℃), excellent high-temperature resistance and electrical conductivity, and is widely used in fields such as electric light sources, semiconductors, and heating elements for high-temperature furnaces. Its manufacturing process mainly includes key steps such as powder metallurgy, plastic processing and drawing, with strict technical requirements. First of all, the preparation of molybdenum powder is the basis for manufacturing pure molybdenum wire. High-purity (≥99.95%) molybdenum trioxide (MoO3) or ammonium molybdate ((NH4)2MoO4) is usually used as the initial raw material and reduced by hydrogen reduction method. In the two-stage reduction furnace, MoO3 is first pre-reduced to MoO₂ at 500 to 700℃, and then further reduced to metallic molybdenum powder at 1000 to 1200℃. By adjusting the hydrogen flow rate and temperature, molybdenum powder with uniform particle size (3 to 10μm) and low oxygen content (<0.1%) can be obtained. Subsequently, the molybdenum powder is formed by isostatic pressing, filled into a rubber mold, and then pressed into billets or square billets under cold isostatic pressing at 200 to 300MPa. Pre-sintering is carried out in a hydrogen atmosphere at a temperature of 1200 to 1400℃, initially increasing the density of the billet. High-temperature sintering is carried out in a vertical furnace or medium-frequency furnace at 1800 to 2200℃ to densify the billet (density ≥98% of the theoretical value), forming processable molybdenum rods.
The processing and manufacturing technology of pure molybdenum wire
The next stage is the hot working phase, which includes forging and rolling. Heat the sintered molybdenum rods to 1200-1500℃ (above the recrystallization temperature), and then carry out multiple forging passes through a forging press to break down coarse grains and improve plasticity. Subsequently, molybdenum rods with diameters ranging from 6 to 20mm are rolled at high temperatures. During this process, surface oxidation must be avoided, and hydrogen protection is usually adopted. Drawing into wire is a key step in manufacturing pure molybdenum wire. First, the surface of the molybdenum rod is treated. The oxide layer is removed by alkaline washing and acid washing (such as NaOH+HNO₃), and then coated with graphite lubricant. Then, hot drawing is carried out at 800 to 1200℃, and the molybdenum rods are drawn to a diameter of 1 to 3mm using tungsten carbide dies. Subsequently, intermediate annealing is carried out in a hydrogen furnace at 1000 to 1300℃ to eliminate work hardening and restore plasticity. Finally, through multiple drawing passes at room temperature or medium temperature (200-400℃), the diameter is gradually reduced to the target size (such as 0.01-1mm), and final annealing is carried out to adjust the performance.
The processing and manufacturing technology of pure molybdenum wire
In the manufacturing process of pure molybdenum wire, post-treatment and inspection are important links to ensure product quality. Surface polishing is accomplished through electrolytic polishing or mechanical polishing to enhance the surface finish. Performance testing includes checking indicators such as tensile strength, elongation, and resistivity to ensure that the product meets application requirements. For instance, molybdenum wires used in electric light sources need to have high ductility. The processing and manufacturing technology of pure molybdenum wire is complex, involving multiple steps such as powder metallurgy, plastic processing and drawing. Each step requires strict control of process parameters to ensure the high performance and high quality of the final product.
Mosten Alloy can produce molybdenum sheet, molybdenum block, molybdenum foil, molybdenum rod, molybdenum wire, molybdenum processing workpiece according to customer demand.
