Study On Mechano-Chemical Effect Of Aluminum Oxide And Aluminum At The Nitrogen Atmosphere

Aluminum nitride(AlN) has been acknowledge as the only material with good over-all properties in ceramic material due to its high thermal conductivity, high electrical resistivity, low thermal expansion coefficient ,moderate hardnessl, bend strength which is better than aluminum oxide and boron oxide, good thermal shock resistance and good corrosion resistance. Now, for AlN powder, there major preparation methods are available: direct nitridation, the carbothermal reduction, chemical vapour deposition and plasma ect. However, there has not article about direct synthesis of aluminum nitride in high-energy ball mill.Recently, there are more and more researchers paid more attention to the mechano-chemistry. It was already proved that the mechanical crushing is a kind of complicated physical-chemical process. The mechano-chemistry is the science on the change of solid status, crystalline structure and physical-chemical changes by mechanical force and at the same time it disclosures the basic principle and rules of the materials.In the paper, studying on the aluminum oxide and aluminum in high-energy ball mill which mechano-chemistry effect affect them on the changing of crystal and influence to the microstructure. All the studies are done by the Pulverisette 4 planetary high-energy ball mill. At the same time, try to research the low cost way to synthesis of the aluminum nitride in high-energy ball mill by studying on changing the gas pressure, the rate of powder and the ball, speed of rotation etc.Draw conclusions by doing a lot of experiments and characterize it by a series of analysis and testing.Firstly, the changes of the density for the aluminum oxide and aluminum powders are tested. The results indicate that with the prolong of the grinding time, the crystal grain size incessantly small and the amorphism on the surface of the grain, the amorphous layer become thicker gradually, and they lead to the density declining.Secondly, the particles size are tested by NSKC-1, and the testing results indicate...