Developing CALPHAD-type models for Zr-C-O high-temperature ceramics considering the effects of short-range-ordering

考虑短程有序效应的 Zr-C-O 高温陶瓷的 CALPHAD 型模型

基本信息

批准号：
21K14393
负责人：
DAVEY THERESA
金额：
$ 2.91万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Early-Career Scientists
财政年份：
2021
资助国家：
日本
起止时间：
2021-04-01 至 2024-03-31
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-21K14393/
关键词：
zirconium carbide CALPHAD ordering phase diagram high entropy ceramic DFT first-principles zirconia point defects

项目摘要

In FY2022, density functional theory (DFT) calculations were performed to further examine the C-O-Zr system, including improving the cluster expansion method calculations calculated previously and generating special quasirandom structures (SQS) to examine disordered phases at different compositions. The lattice parameter was evaluated for these results and mapped as planned across the calculated composition space. Results were presented at international conferences: MS&T2022 (in-person in Pittsburgh, USA) - Invited, ICAMMM (virtually in Chandigarh, India) - Invited keynote, and international seminars: Thermo-Calc (virtually in Stockholm, Sweden) research webinar - Invited, UC Davis (in-person in Davis, USA) research seminar - Invited.The aim of the proposed work was to explore the C-O-Zr system to understand oxidation behaviour of the ultra-high temperature ceramic (UHTC) ZrC. In very recent years, an exciting new field has emerged of “high-entropy” UHTCs based on the ZrC structure, where Zr is replaced with multi-principal component refractory transition metals such as Zr, Hf, Ti, Ta, Nb. These high-entropy UHTCs have improved oxidation resistance compared to the single metal carbides such as ZrC. Therefore, in addition to exploring the C-O-Zr phase diagram, the properties of some high-entropy UHTCs have also been explored. Results from this work was presented at the ICACC2023 conference (in-person in Daytona Beach, USA), and following this an abstract submitted to ECerS 2023 (to take place in Lyon, France, in July 2023) has been selected as a highlight presentation.

2022财年，进行了密度泛函理论（DFT）计算，以进一步检查C-O-Zr体系，包括改进之前计算的团簇展开法计算，并生成特殊的准随机结构（SQS）以检查不同成分的无序相。对这些结果进行了评估，并按计划在计算的成分空间上进行了映射。结果已在国际会议上公布：MS&T2022（在美国匹兹堡亲自参加）- 受邀， ICAMMM（实际上在印度昌迪加尔）- 受邀主题演讲和国际研讨会：Thermo-Calc（实际上在瑞典斯德哥尔摩）研究网络研讨会 - 受邀、加州大学戴维斯分校（在美国戴维斯亲自参加）研究研讨会 - 受邀。拟议的工作是探索 C-O-Zr 体系，以了解超高温陶瓷 (UHTC) ZrC 的氧化行为。近年来，出现了一个令人兴奋的新领域。基于ZrC结构的“高熵”UHTCs的出现，其中Zr被Zr、Hf、Ti、Ta、Nb等多主成分难熔过渡金属取代，这些高熵UHTCs与ZrC结构相比具有改善的抗氧化性。因此，除了探索C-O-Zr相图之外，一些高熵UHTC的性能也得到了研究。这项工作的结果已在 ICACC2023 会议（在美国代托纳比奇举行）上提出，随后提交给 ECerS 2023（将于 2023 年 7 月在法国里昂举行）的摘要被选为突出演示。