THE EFFECT OF GRAIN BOUNDARY PRECIPITATION ON THE SUPERPLASTICITY OF Al-Li ALLOYS H. YOSHIDA, S. HIRANO, Y. BABA, T. TSUZUKU et A. TAKAHASHI J. Phys. Colloques, 48 C3 (1987) C3-269-C3-275 DOI: 10.1051/jphyscol:1987330