The binary Ba - Cu system was investigated experimentally by DTA and s
olution calorimetry. The DTA results showed a higher temperature for t
he peritectic reaction L + Ba = BaCu13 than the previously reported va
lues. The new experimental results were combined with phase diagram da
ta from the literature. The thermodynamic consistency between all data
was investigated using a optimising program. The phase diagram was ca
lculated from the optimised data.