X-Ray phase analysis, DTA and metallographic examination are used to c
onstruct the pseudobinary sections and projection of the liquidus surf
ace for the Al - Mg - NdAl2 system. In the region under study the bina
ry (e(1) - e(10)) and ternary (E(1) - E(5)) eutectic points and the te
rnary peritectic (P-1) point are established. The melting temperature
of a new ternary compound eta(1) is determined.