PHOSPHORUS AND SULFUR SEGREGATION IN MODEL HEAT RESISTING NICKEL ALLOY
Harmful impurity (sulfur and phosphorus) and microalloying additives (boron and lanthanum) competition at model heat resisting nickel alloy of Ni-Co-Cr-Al-Ti-W-Mo-Nb system inner interfaces segregations formation was investigated. It was shown that sulfur and phosphorus form segregation on grain boundaries and interphase interfaces «inclusion - matrix». Boron and lanthanum force out sulfur and phosphorus from interfaces, and these microalloying additives action mechanisms are different: boron refines and strengthens grain boundaries, and the lanthanum connects sulfur and phosphorus in favorable morphology inclusions.