Accession Number : AD0706221

Title :   IMPLEMENTATION OF ADVANCED TECHNOLOGY FOR CAST METALS.

Descriptive Note : Final rept.,

Corporate Author : DARTMOUTH COLL HANOVER N H THAYER SCHOOL OF ENGINEERING

Personal Author(s) : Colligan,George A.

Report Date : MAR 1970

Pagination or Media Count : 63

Abstract : Phase equilibrium studies in the system ZrO2-MgO locate the eutectoid point at 13.7 mole % MgO at 1400C. Disagreement in the literature as to the position of the eutectoid point can be attributed to the difficulty in the attainment of equilibrium or method of analysis. A model of the stabilization process based primarily upon entropy of mixing effects alone satisfactorily explains the relative positions of the tetragonal + cubic - cubic phase field boundaries observed experimentally in various binary zirconia systems. Commercially significant conclusions are drawn as a result of these studies with respect to the process variables, time, temperature, and stabilization compound addition and identity to derive the true benefits of high quality ZrO2 refractory bodies. (Author)

Descriptors :   (*ZIRCONIUM OXIDES, PHASE STUDIES), (*REFRACTORY MATERIALS, ZIRCONIUM OXIDES), STABILIZATION, PHASE DIAGRAMS, THERMODYNAMICS, MAGNESIUM OXIDES, CASTINGS, STEEL

Subject Categories : Ceramics, Refractories and Glass
      Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE