DEFORMATION-BEHAVIOR OF PARTICLE STRENGTHENED P M-ALUMINUM ALLOYS UNDER CREEP LOADS/

Three different powder metallurgy (P/M) aluminium alloys (AlC001, AlC1 O1 and AlC3O1) were tested under tension and compression creep loads. The materials were manufactured by mechanical alloying and subsequent consolidation by cold compaction and hot extrusion. The tension and co mpressison tests were carried out at 300 degrees C, 400 degrees C and 500 degrees C. In tension creep tests, the applied stress was chosen t o result a fracture life ranging between few minutes and 4000 hours. I n compression creep tests, the applied stress was chosen to have a tim e to the loss of stability from 0.1 to 100 hours. These materials were also microstructurally inspected. The role of interfacial microstruct ure in the fracture of the strengthened P/M aluminium alloys were exam ined using SEM- and TEM-methods to study the correlation of the micros tructure with the creep behaviour of these materials. If was found tha t the creep resistance increases with the increase of the volume fract ion of Al2O3 and Al4C3 in both tension and compression. Also, there is a distinct reduction of the ductility with increasing the volume frac tion, but, it can withstand the applications at high temperatures up t o 500 degrees C, and the tertiary creep stage does not appear in AlC30 1 in tension creep tests.