Molybdenum electrode mainly produces by the powder metallurgy method. To produce high quality molybdenum electrode in addition to control the production process, but also should have a high quality molybdenum powder as a raw material.
To produce good properties molybdenum powder first to use high-purity ammonium molybdate as raw material and to select the appropriate producing technology, so that it can eliminate low melting point impurity and significantly reduced oxygen content. In addition, according to studies found molybdenum powder which is middle particle and close to normal distribution are suitable for produce high quality molybdenum electrodes.
On the other hand, molybdenum electrode performance also depends greatly on production process control. For example employ smooth and slow heating, during heat preservation to minimize the temperature difference between inside and outside of molybdenum electrode blank and to prevent internal hidden cracks and other defects cause by excessive thermal stress. Besides, to ensure the resulting particle are fine and uniform. Secondly, during forging can through hydrogen to molybdenum wire muffle furnace and then precisely controlling the heating temperature and time. There are through the hydrogen to protect electrode blank oxidation, to avoid increase the oxygen content of molybdenum electrodes and forging loss.
The following are production process of molybdenum electrode:
1.Heating paramolybdate into molybdenum trioxide.
2.Molybdenum trioxide by through hydrogen and heat reduction becomes molybdenum powder.
3.Sealed molybdenum powder into the oil resistant rubber mold and then in Ø820 × 1600mm isostatic equipment under 200~300MPa pressure molded into a certain density sintered molybdenum blanks.
4.The molybdenum powder under hydrogen protection sintering on intermediate induction furnace to obtain molybdenum blank which is close to dense sintered molybdenum blank.
5.The molybdenum blank protection by hydrogen to hot forging, warm forging to obtain molybdenum electrode blank.
6.Finally, after machining become molybdenum electrodes.