THIS RESEARCH PROGRAM WILL DEVISE TEST AND CHARACTERIZE THE APPLICATION OF W AND COMPOSITE W-ZRC COATINGS ONTO SURROGATE NUCLEAR FUEL POWDERS (ZRO2 AND CEO2). THESE COATINGS PROVIDE NECESSARY BARRIER PROTECTION FROM DELETERIOUS CHEMICAL REACTIONS OF THE FUEL WITH THE SURROUNDING PROPULSION ENVIRONMENT. TO DATE NUCLEAR THRUST PROPULSION BASED MATERIALS ARE COATED BY CHEMICAL VAPOR DEPOSITION (CVD); THIS PROGRAM WILL EXPAND THE COATING TOOLKIT TO INCLUDE PHYSICAL VAPOR DEPOSITION (PVD). SPECIFICALLY THE PROGRAM WILL APPLY THESE COATINGS USING MAGNETRON SPUTTERING. A NOVEL ROTATING CATHODE AND BED OF SPHEROIDIZED POWDERS WILL MOVE TRADITIONAL LINE-OF-SITE PVD GROWTH FROM 2D PLANAR SURFACES TO BEING ABLE TO COAT 3D MORPHOLOGIES (POWDERS). THIS TECHNOLOGY HAS BEEN SHOWN TO BE VIABLE AND SCALABLE MEANS OF COATING KILOGRAMS OF POWDERS PER WEEK SATISFYING THE PROPOSAL CALL. THESE COATINGS WILL CREATE CORE-SHELL POWDERS THAT WILL BE CONSOLIDATED AND HOT ISOSTATIC PRESSED INTO BILLETS. THE INDIVIDUAL CORE-SHELL POWDERS AND CERMET BILLETS CREATED BY THE COATED POWDERS WILL BE EVALUATED THROUGH THERMAL CYCLING THERMO-MECHANICAL LOADING AND HOT HYDROGEN TESTING. THE STABILITY OF THE COATINGS ON THE SURROGATE FUEL WILL BE QUANTIFIED USING THREE-DIMENSIONAL CHARACTERIZATION TECHNIQUES THAT SPAN THE ATOMIC TO HUNDREDS OF MICRON-LENGTH SCALES. THIS WILL PROVIDE FOR AN UNPRECEDENTED UNDERSTANDING OF THE COATING S MICROSTRUCTURAL STABILITY FROM WHICH THE UNDERLYING STRUCTURE-PROPERTY-PERFORMANCE BEHAVIOR OF THE COATINGS PROTECTION WILL BE REVEALED. THE PROGRAM WILL EVEN QUANTIFY HYDROGEN MIGRATION VIA ATOM PROBE TOMOGRAPHY USING DEUTERIUM TRACER ATOMS. THESE RESEARCH OBJECTIVES WILL BE ACHIEVED THROUGH COLLABORATIONS BETWEEN UNIVERSITY-INDUSTRIAL COLLABORATIVE PARTNERSHIPS