When a eutectic melt is undercooled below its liquidus T-1 by a critical am
ount, it undergoes metastable liquid-state spinodal decomposition. The resu
lting morphologies can be described as intermixing undercooled liquid netwo
rks of characteristic wavelength lambda. At a temperature substantially bel
ow T-1, lambda can be <100 nm. When lambda less than or equal to 100 nm, th
e undercooled liquid networks break up into nanometer-size droplets/strips
driven apparently by surface tension. The morphologies of the tiny droplets
/strips can be frozen by subsequent crystallization. The as-crystallized sp
ecimen is a nanostructured material. It is microvoid free and the size of t
he constituent grains is rather uniform. Two systems, Pd40.5Ni40.5P19 and P
d82Si18, were chosen to illustrate the synthesis process.