Research On Improvement Molybdenum Powder Agglomeration And Its Application

Molybdenum powder is the raw material of preparation molybdenum processing products, their physical and chemical properties and organizational structure largely determines the subsequent processing of product features and quality characteristics. The general reduced molybdenum powder mainly exist the following problems:the purity is not high, the physical property is volatility,the powder has a wide size distribution,the particle morphology isn’t the same, fine powder reunites seriously. This may cause inhomogeneous structure and grain size of green and sintered specimen in the follow-up process of pressing and sintering; especially, the presence of aggregates of molybdenum powder and sintered organizations can directly lead to the emergence of the holes, cracks and other defects in the sintered specimen, thus the formation of poor quality products and affect the subsequent pressure processing.We investigated thick particles and aggregated particles of molybdenum powder with a scanning electron microscope observation on high multiples, and found out thick particles and aggregated particles of molybdenum powder are reunited by a number of small powder.To eliminate and improve the reunion of the molybdenum powder, we analysis the mechanism and the structural of the molybdenum powder agglomeration, and propose measures to eliminate and improve the reunion of the molybdenum powder depend on this. Three Experiments were carried out:improve the molybdenum powder bulk density and tap density, contrast the air current pulverization molybdenum powder and Preparation of TZC molybdenum alloy Piercing-Mandrel by air current pulverization the oversize molybdenum powder. And we test the performance of molybdenum powder and follow-up molybdenum products and detection analysis them.Test results showed that:advanced physical crushing technology can effectively eliminate the gross and aggregate particles in molybdenum powder, increase the bulk density and tapped density, keep the chemical purity and oxygen content, and improve the particle size. After molybdenum powder mechanical crushed by physical crusher, the particle size is well-distributed and the basic normal distribution is presented. Through physical crushing the reduced molybdenum powder, the specific surface area and the activity of powder are improved, which can activate sintering. After physical crushing, oversize molybdenum powder which agglomerated by many fine particles are loosed, and the phenomenon of powder agglomerated and cohered seriously are eliminated. The pressing performance of the powder is well, and the density of molybdenum plug is improved above1.5%, which meets the production requirements of molybdenum products. The powder mentioned can be directly used as raw material for molybdenum plug produced. Meanwhile, we find an effective treatment route of oversize molybdenum powder.