Previous research has suggested that significant improvement on DDC resistance of alloy 690 weld metal can be obtained if second phase precipitation during welding is optimized with some carbide and nitride forming elements additions. Therefore, this systematic theoretical and experimental work on the effect of Nb and Ti additions to the precipitation of second-phase particles during welding of 690-like alloy come to help on the understanding of the DDC phenomena and the development of DDC resistant alloys. The critical precipitation temperatures, phase fractions and atomic partitioning in microstructure were among the factors analyzed. The experimental work involved test samples production by arc melting of ERNiCrFe-7 modified with up to 3 %wt of Ti and/or Nb additions and characterization by analytical electron microscopy. The continuous cooling phase transformations taking place during cooling after welding where addressed using Calphad-based numerical simulation. (Ti,Nb)(C,N), Cr₂₃C₆, and Ni₃(Ti,Nb,Al) were observed and their precipitation kinetics was evaluated. The measured precipitates chemical composition and fractions were closely correlated with theoretical predictions. It was observed how Ti and/or Nb additions are useful to induce increasing precipitation of primary carbonitrides and simultaneously to inhibit secondary precipitation of chromium rich carbides. However, these Ti and/or Nb additions lead to strong atomic segregation near the interdendritic regions and, consequently, to intense decreasing of kinetic solidus temperature and precipitation of gamma-prime.  Therefore, these additions should be keep within critical levels to maximize the carbonitrides formation while controlling the collateral effects.