Nb掺杂Ba－Sn－W－O系半导瓷材料特性的研究

On the Properties of the Semiconducting Ceramicscthg Ceramics of an Nb-Doped Ba-Sn-W-O System

研究了Ｎｂ掺杂Ｂａ－Ｓｎ－Ｗ－Ｏ系复合陶瓷材料的显微结构及电导特性，研究表明，该系列材料是主导电相为Ｂａ（Ｓｎ，Ｎｂ）Ｏ＿３的低Ｂ值ＮＴＣ热敏电阻材料，Ｎｂ＿２Ｏ＿５的引入，在烧结过程中可能在两主晶相晶粒的表层分别产生Ｖ＿（Ｂａ）和Ｖ＿ｏ，影响烧结过程中的扩散机制。当Ｎｂ＿２Ｏ＿５的引入量约为１．０ｍｏｌ％时，可促进该系列材料烧结成致密瓷。

The microstructure and electrical properties of the composite ceramics of an Nb-dopedBa-Sn-W-O system have been investigated. These materials are thermistors of low B valueand with negative temperature coefficient with Ba(Sn,Nb)O_3 as the main conductive phase.The doping of Nb_2O_3 may resuIt in the formation of V_(Ba) and V_o at the boundaries of two dif-ferent main crystalline phases,respectively, thus affecting the diffusion mechanism in sinter-ing. When the amount of Nb_2O_3 introduced reaches about 1.0 mol%,densified ceramics willbe obtained.