Phase evolution and mechanical properties of novel nanocrystalline Y_(2)(TiZrHfMoV)_(2)O_(7) high entropy pyrochlore

作     者：G.Karthick Lavanya Raman B.S.Murty G.Karthick;Lavanya Raman;B.S.Murty

作者机构：Department of Metallurgical and Materials EngineeringIndian Institute of Technology MadrasChennai600036India Indian Institute of Technology HyderabadKandi502285India 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2021年第82卷第23期

页      面：214-226页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：The authors are grateful to Prof T. Pradeep for the XPS facility. The authors thank the Nanomechanics and Nanomaterials lab for the Nanoindentation measurement. Mr. Karthick is grateful to Ms. Nandhini J Usharani for her assistance in analysing the XPS results and fruitful technical discussions. Mr. Karthick also acknowledges Ms. Tripta Parida for helping with TEM studies 

主　　题：High entropy pyrochlores Reverse co-precipitation B site substitution Hardness Young’s modulus 

摘      要：High entropy pyrochlores(HEP)are potential candidates as dispersoids in the oxide dispersed strengthened steels or alloys,which can be used in nuclear reactors and supercritical *** the first time,HEP oxides Y_(2)(TiZrHfMoV)_(2)O_(7) were synthesized with Y_(2)Ti_(2)O_(7) as a base structure with the B site(Ti)substituted with five cations through reverse co-precipitation technique in the nanocrystalline form at lowest synthesis *** synthesis parameters for Y_(2)(TiZrHfMoV)_(2)O_(7)(5C)and other derived compositions(five compositions of four cationic systems with each cation eliminated at B site from 5 C)are optimised to obtain lower crystallite and particle sizes.5C has a smaller crystallite size(27 nm)than other single-phase *** cation’s influence,oxidation state,and oxygen vacancy in the phase formation were analysed through *** single-phase HEPs are consolidated through spark plasma sintering.Y_(2)(TiZrHfMo)_(2)O_(7)(4 C-V)shows the highest hardness among the compositions reported so far due to its finer grain size,and Y_(2)(TiHfMoV)_(2)O_(7)(4 C-Zr)has a higher Young’s modulus compared to other single-phase composition due to its higher degree of order in the structure.