The effects of additives (Cr, Nb, Dy, and Bi) on microstructure, electrical properties, dielectric characteristics, and aging behavior of ZnO-V 2 O 5 -MnO 2 -Co 3 O 4 -La 2 O 3 (ZVMCL) ceramics were systematically investigated. The phase formed in common for all ZVMCL ceramics modified with various additives consisted of ZnO grain as a main phase, and Zn 3 (VO 4 ) 2 and ZnV 2 O 4 as the secondary phases. The sintered density and average grain size were in the range of 5.4-5.54 g/cm 3 and

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... μm, respectively. The ZVMCL ceramics modified with Cr exhibited the highest breakdown field (6,386 V/cm) and the ZVMCL ceramics modified with Nb exhibited the lowest breakdown field (3,517 V/cm). All additives enhanced the nonlinear coefficient (α), by a small or large margin, in particular, additives such as Bi and Nb noticeably increased the nonlinear coefficient, with α=25.5 and α=23, respectively. However, on the whole, all additives did not improve the stability against a DC stress, compared with ZVMCL ceramics.