Method of coating preformed ceramic cores

摘要: THIS INVENTION RELATES TO A METHOD OF COATING PREFORMED CERAMIC CORES WITH THIN LAYER REFRACTORY OXIDE, SAID OXIDE SERVING AS REACTION BARRIER BETWEEN THE CORE ANDMOLTEN METALS, CONTAINING REACTIVE ALLOYING ELEMENTS. MORE SPECIFICALLY, FORMING CONTINUOUS IN SITU ON BY IMMERSING MOLTEN METAL BATH CONSISTING NON-REACTIVE BASE SOLVENT SUCH NICKEL OR COBALT, AND AT LEAST ONE SOLUTE WHOSE FREE ENRGY FORMATION IS LESS THAN MINUS 160 KILLOCALORIES PER MOLE OXYGEN 1260* C., ALUMINUM, ZIRCONIUM HAFNIUM.