Abstract
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 Al2O3-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 Al2O3-DS alloy powder which had poor sinterabilities was accelerated by undergoing pre-sintering treatment in the air atmosphere prior to ordinary sintering.
Especially, from Al2O3-DS alloy powder which showed superior sinterability the application to the porous gasdiffusional electrode in the usage at high temperature (Ni-Al2O3), or production of the large billet for the hevy electric parts (Cu-Al2O3) might be expected.
