Grain size refinement of additive manufactured Ce-TZP ceramics by coupled two-step pre-sintering and HIP  

作　　者：Ruoshi Zhao Hongbing Yang Xintong Liu Hezhen Li Chang-An Wang Jing Ma Yanhao Dong 

机构地区：[1]State Key Lab of New Ceramics and Fine Processing,School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China

出　　处：《Journal of Advanced Ceramics》2024年第5期621-629,共9页先进陶瓷（英文）

基　　金：the National Key R&D Program of China(No.2023YFB3812000),the National Natural Science Foundation of China(No.51972189);the Tsinghua University Initiative Scientific Research Program(No.20233080030).

摘　　要：Ceria-stabilized tetragonal zirconia polycrystal(Ce-TZP)has exceptional fracture toughness and flaw tolerance due to facile t‒m phase transformation toughening.However,its wider-range applications are limited by its relatively low strength due to its large grain size and low transformation stress,which results in yield-like failure.Here,we combined additive manufacturing(AM),pressureless two-step sintering,and hot isostatic pressing(HIP),and addressed the challenging grain size refinement problem in Ce-TZPs.We successfully produced dense ultrafine-grained Ce-TZP ceramics with an average grain size below 500 nm,a three-point bending strength above 800 MPa,and a single-edge-notch-beam fracture toughness in the range of 11‒12 MPa·m^(1/2).The critical roles of processing design,mixed Ce valences,and under-vs.over-stabilization of tetragonal polymorphs were noted.Our work offers insights and strategies for the future development of stronger and tougher Ce-TZP ceramics that can compete with tetragonal yttria-stabilized zirconia in various applications,including additive manufacturing.

关 键 词：ZIRCONIA additive manufacturing(AM) two-step sintering hot isostatic pressing(HIP) grain size refinement 

分 类 号：TQ174.758.12[化学工程—陶瓷工业]