The densification mechanism and phase transition of porous Zr based getter alloy prepared by powder metallurgy during vacuum sintering were described.The results reveal that Zr content in the alloy is decreased and Al3Zr5 phase content is obviously increased with increasing in sintering temperature and in holding time

resulting in the increase of activation temperature of the getter alloy.With sintering temperature lower than 1 000 ℃

solid sintering is dominated in sintering process with low volumetric contraction.With the sintering temperature more than 1 000 ℃

the volumetric contraction is sharply decreased due to the presence of minor liquid phase

resulting in the decrease of porosity.The porosity rate can be obviously increased with increasing in pore-forming agent.In addition

with increasing in sintering temperature

the contraction rate is gradually declined.