掺杂Y^(3+),Mn^(2+)的钛酸钡基无铅热敏陶瓷的PTC效应研究

Preparation of Y,Mn co-doped Barium Titanate BBNT Lead-free PTCR Ceramics by Solid Phase Reaction Method

采用传统固相反应法制备了(Y,Mn)共掺的0.99BaTiO_(3)-0.01(Bi_(0.5)Na_(0.5))TiO_(3)(BBNT)高温无铅正温度系数电阻(PTCR)陶瓷.XRD图谱表明了掺杂不会改变材料的物相结构,电阻温度特性表明了所有样品都能够实现半导化.室温电阻随着Y^(3+)的掺杂量的掺入会呈现变化,其中掺杂0.2mol%Y^(3+)的BBNT陶瓷具有最好的综合性能,在0.2mol%Y^(3+)浓度下,0.04mol%Mn^(2+)掺杂后制备的BBNT陶瓷,室温电阻约为700Ω,居里温度约为140℃,电阻升阻比在2.8个数量级左右.当Mn^(2+)>0.07mol%时,室温电阻突增,PTC性能也大大降低.该材料在可控硅触发电路的温度补偿中具有一定应用前景.

The(Y,Mn)co-doped 0.99BaTiO3-0.01(Bi0.5Na0.5)TiO3(BBNT)ceramics with high-tempera-ture lead-free positive temperature coefficient resistance(PTCR)were prepared by traditional solid state reaction method.The XRD spectrum shows that doping will not change the phase structure of the material,and the resis-tance temperature characteristic shows that all samples can achieve semiconducting.The resistance at room tem-perature will change with the doping amount of Y3+.Among them,0.2mol%Y3+doped Y-BBNT ceramics have the best comprehensive performance.At 0.2mol%Y3+concentration,the room temperature resistance of Y-BBNT ceramics prepared after 0.04mol%Mn2+doping is about 7002,and the Curie temperature is about 1409C.The resistance rise resistance ratio is about 2.8 orders of magnitude.When Mn2+>0.07mol%,the room temperature resistance increases suddenly,and the PTC performance decreases greatly.These observations may bring a certain applications for these materials in temperature compensation of SCR trigger circuit.