DEGRADATION OF RSP PM AL-8FE-4CE DURING CREEP

The creep behavior of Al-8Fe-4Ce powder metallurgy alloy produced by r apid solidification processing (RSP/PM alloy) was studied within the 6 23 to 773 K temperature range and at initial stresses ranging from 10 to 52 MPa. The activation energy, Q, for creep in RSP/PM Al-Fe-Ce allo y is 2.3 Q(L), where Q(L) is the activation energy for lattice diffusi on in pure aluminum and the stress exponent is 8.6. The high-temperatu re creep deformation is associated with deformation of matrix and Al13 Fe4 incoherent particles. In addition, particle coarsening is an impor tant factor in alloy degradation. The formation and growth of cavities during creep at all stress levels at 698 K is also a contributing fac tor.