Method of pressureless sintering production of densified ceramic composites

摘要

Methods of making and compositions of dense sintered ceramic nano- and micro-composite materials that are highly stable in a variety of conditions and exhibit superior toughness and strength. Liquid feed flame spray pyrolysis techniques form a plurality of nanoparticles (e.g., powder), each having a core region including a first metal oxide composition comprising Ce and/or Zr or other metals and a shell region including a second metal oxide composition comprising Al or other metals. In certain aspects, the core region comprises a partially stabilized tetragonal ZrO₂ and the shell region comprises an α-Al₂O₃ phase. The average actual density of the ceramic after sintering is greater than 50% and up to or exceeding 90% of a theoretical density of the ceramic.