About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
|
Symposium
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Manufacturing and Processing of Advanced Ceramic Materials
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Presentation Title |
Grain Size Refinement of Additive Manufactured Ce-TZP Ceramics by Coupled Two-Step Pre-Sintering and HIP |
Author(s) |
Ruoshi Zhao, Hongbing Yang, Xintong Liu, Hezhen Li, Chang-An Wang, Jing Ma, Yanhao Dong |
On-Site Speaker (Planned) |
Ruoshi Zhao |
Abstract Scope |
Ceria-stabilized tetragonal zirconia polycrystal (Ce-TZP) has exceptional fracture toughness and flaw tolerance, due to facile t-m phase transformation toughening. Yet its wider-range applications are limited by relatively low strength, due to large grain size and low transformation stress resulting in yield-like failure. Here we combined additive manufacturing, pressureless two-step sintering, and hot isostatic press (HIP) and addressed the challenging grain size refinement problem in Ce-TZP. We successfully produced dense ultrafine-grained Ce-TZP ceramics with average grain size below 500 nm, three-point bending strength above 800 MPa, and single-edge-notch-beam fracture toughness in the range of 11-12 MPa·m1/2. 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 in future development of strong tough Ce-TZP ceramics to compete with tetragonal yttria-stabilized zirconia in applications including additive manufacturing. |