機械的合金化(MA)法を応用した分散強化形合金粉の開発 Development of Dispersion Strengthened Alloy Powder by the Application of Mechanical Alloying(MA)
A new oxide dispersion strengthened (ODS) alloy powders were developed by the application of a novel process which is the combination of dual stages such as (1) mechanical alloying of the metal powder with various metalalkoxides in the air atmosphere and heat (2) treatment in a hydrogen atmosphere which followed stage (3) operation. By this process very fine oxide particles were formed and dispersed in the metal matrix, and consequently the metal matrix was strengthened remarkably. Moreover, among various ODS alloy powders obtained by this process, only Al<SUB>2</SUB>O<SUB>3</SUB>-dispersion strengthened (DS) alloy powder showed very superior sinterability. This phenomenon was able to be interpreted by the thermal stability of the excess dislocations introduced in the metal matrix by mechanical alloying. It was also found that sintering of ODS alloy powders except for Al<SUB>2</SUB>O<SUB>3</SUB>-DS alloy powder which had poor sinterabilities was accelerated by undergoing pre-sintering treatment in the air atmosphere prior to ordinary sintering.<BR>Especially, from Al<SUB>2</SUB>O<SUB>3</SUB>-DS alloy powder which showed superior sinterability the application to the porous gasdiffusional electrode in the usage at high temperature (Ni-Al<SUB>2</SUB>O<SUB>3</SUB>), or production of the large billet for the hevy electric parts (Cu-Al<SUB>2</SUB>O<SUB>3</SUB>) might be expected.
粉体および粉末冶金 45(10), 981-985, 1998-10-15
Japan Society of Powder and Powder Metallurgy