Effect of Phase Structure Evolution on Thermal Expansion and Toughness of (Nd1-xScx)2Zr2O7 (x = 0, 0.025, 0.05, 0.075, 0.1) Ceramics. Issue 2 (February 2017)

• Record Type: Journal Article
• Authors: Zhao, Xiaoxiang; Guo, Lei; Wang, Caimei; Zhang, Yu; Ye, Fuxing
• Is Part Of: Journal of materials science & technology. Volume 33:Issue 2(2017:Feb.)
• Page Start: 192
• Page End: 197
• Publication Date: 2017-02
• Subjects: Thermal barrier coating -- Nd2Zr2O7 -- Doping -- Phase structure -- Thermal expansion coefficient -- Toughness; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2016.03.015
• Languages: English
• ISSNs: 1005-0302

Abstract

Abstract : Nd2 Zr2 O7 is being explored as an alternate thermal barrier coating (TBC) material for operating above 1300 °C, and great effort has been made to enlarge its thermal expansion coefficient (TEC) and improve its toughness. In this study, Sc2 O3 was doped to Nd2 Zr2 O7 . The phase structure, TECs and toughness of (Nd1- x Sc x )2 Zr2 O7 ( x = 0, 0.025, 0.05, 0.075, 0.1) compounds were investigated. (Nd1- x Sc x )2 Zr2 O7 ( x = 0, 0.025, 0.05, 0.075) exhibited pyrochlore structure, while (Nd0.9 Sc0.1 )2 Zr2 O7 consisted of pyrochlore and fluorite phases. With the increase of the Sc2 O3 content, the ordering degree of the pyrochlore in the compounds decreased. In (Nd1- x Sc x )2 Zr2 O7 series, (Nd0.925 Sc0.075 )2 Zr2 O7 exhibited the largest TEC, while the toughness of the compounds increased with increasing the Sc2 O3 content. The related mechanisms were discussed based on the crystal structure analysis. Considering the TEC and toughness, 10 mol% Sc2 O3 was suggested as the optimal doping content for Nd2 Zr2 O7 ceramic.