| 【文章摘要】 Gd_2Zr_2O_7 has been considered as a promising thermal barrier coating candidate,but its toughness and thermal expansion coefficient(TEC) need to be improved.In this study,Gd_(2-x)Zr_(2+x)O_(7+x/2)(x = 0,0.1,0.3,0.5,0.7) compounds were produced to improve the toughness and enlarge the TEC.Gd_2Zr_2O_7 and Gd_(1.9)Zr_(2.1)O_(7.05) exhibited pyrochlore structure,while Gd_(2-x)Zr_(2+x)O_(7+x/2)(x=0.3,0.5,0.7) consisted of pyrochlore and t'-ZrO_2 phases.With increasing ZrO_2 content,the pyrochlore in the compounds had decreased lattice parameter,and its ordering degree decreased when x≤0.3,then it almost kept unchanged with higher ZrO_2 content.Among the Gd_(2-x)Zr_(2+x)O_(7+x/2) ceramics investigated,the toughness of the compounds increased with increasing ZrO_2 content,while Gd_(1.7)Zr_(2.3)O_(7.15) exhibited the largest TEC.The related mechanisms were discussed in detail. |