A RELAXATIONAL INTERNAL FRICTION PEAK OF C IN A Co-BASE SUPERALLOY
WANG Jhuhe; DAI Tongfu; SHI Changxu (Institute of Metal Research; Academia Sinica; Shenyang)
Cite this article:
WANG Jhuhe; DAI Tongfu; SHI Changxu (Institute of Metal Research; Academia Sinica; Shenyang). A RELAXATIONAL INTERNAL FRICTION PEAK OF C IN A Co-BASE SUPERALLOY. Acta Metall Sin, 1986, 22(5): 85-88.
Abstract An internal friction peak near 370℃ is observed for a Co-base superalloy Co-22Ni-22Cr-14W. This is due to the C-C pairs of the interstitial solute C atoms which make the lattice distortion in different directions under stress, and is fairly corresponding with the segregation of C atoms, the precipitation of carbide and the ductility of the alloy. The C atoms segregate continuously toward the vicinity of grain boundary, and the peak reduces continuously its own height as the prolongation of aging time. The peak will soon disappear while the carbide precipitates out. The addition of La may influence the internal friction peak as well as the microstructure and mechanical properties of the alloy The increase of its activation energy and the retardation of carbide precipitated may be caused by the increase of La content in the alloy.
