Investigation of the behaviour of rare earth element cerium in aluminium–lithium alloys by the method of internal friction

The behaviour of rare earth element Ce in 2090 Al–Li alloys has been studied by the method of low frequency internal friction. The results showed that trace solution Ce atoms can segregate at the grain boundary of Al–Li alloys, improve the grain boundary strength of the alloys, increase the activation energy of the grain boundary, and decrease the tendency of inter-granular fracture of the alloys. Rare earth element Ce can decrease the tendency of reduction of the elastic modulus of 2090 Al–Li alloys after heat cycle, which would benefit the high temperature mechanical properties.