题名复合NTC 热敏电阻材料La(Mn, Co)O3/Ba(Sn, Sb)O3-Ni0.66Mn2.34O4的制备与电性能研究
作者黄翠萍
学位类别硕士
答辩日期2016-05-27
授予单位中国科学院大学
授予地点北京
导师常爱民
关键词复合NTC 热敏电阻陶瓷 尖晶石相 钙钛矿相 电性能 热稳定 性
学位专业材料物理与化学
中文摘要负温度系数(NTC,Negative Temperature Coefficien)热敏电阻具有灵敏度高,响应快且成本低廉,体积小等众多优点,NTC热敏电阻材料在温度传感器,温度补偿器件,金属热电偶,半导体陶瓷等领域都有广泛的应用。目前,最常用的一种NTC热敏电阻器是由Mn、Ni、Co、Cu等过渡金属元素氧化物组成的通式为AB2O4的单一结构的尖晶石相。此类材料的应用温区较窄,且烧结后材料内部缺陷分布的不均匀性使材料的电性能容易发生改变,在中温区使用时稳定性较差。因此,探索新型的使用温区较宽、稳定性较好的热敏电阻材料具有重要意义。复合材料作为一种具有很大发展前景的材料,为材料性能的改变发挥了重要作用。利用复合材料的乘积效应和加和性,可以对材料的微观结构和电性能进行控制,从而获得单相材料无法得到的性能。本论文将复合与掺杂技术应用到传统的尖晶石结构中,采用氧化物固相法,对(LaMn1-yCoyO3)x-(Ni0.66Mn2.34O4)1-x (0≤x≤0.5,0≤y≤0.5)和(BaSn1-ySbyO3)x-(Ni0.66Mn2.34O4)1-x (0≤x≤0.5,0≤y≤0.5)复合材料体系进行了研究。结合激光粒度分析、TG/DSC、DIL、XRD、SEM、EDS及电阻温度等测试分析手段对制备的热敏电阻材料粉体和陶瓷体样品进行了表征和分析。研究了体系中的掺杂量、复合度及工艺条件等对复合材料微观结构和电性能的影响及变化规律,并探讨了其导电机理。具体研究内容如下:(1) 采用氧化物固相法制备了单相LaMn1-yCoyO3 (0≤y≤0.5)和Ni0.66Nn2.34O4氧化物粉体材料。结合XRD确定了LaMn1-yCoyO3 (0≤y≤0.5)和Ni0.66Nn2.34O4的最佳煅烧温度分别为1000 ℃和950 ℃。烧结后的复合材料主要由立方尖晶石相和正交钙钛矿组成,复合材料中钙钛矿相的复合量、Co的掺杂量都对复合陶瓷材料的微观结构和形貌产生一定程度的影响。(2) 当掺杂量y为0.5时,复合陶瓷材料(LaMn0.5Co0.5O3)x-(Ni0.66Mn2.34O4)1-x (0≤x≤0.5)的电阻率和B值均随着LaMn0.5Coy0.5O3含量的增加而减小,其室温电阻率ρ25和材料常数B的变化范围分别是4767~20 Ω?cm和3970~1573 K;将复合材料于125 ℃老化1000 h,其电阻漂移率ΔR/R0随钙钛矿相含量x的增加而降低,当x从0增加到0.5,ΔR/R0从1.8 %降低到0.28 %,稳定性得到提高。当x=0.2时材料复合材料的电阻率随Co掺杂量的增加而减小,ρ25和B值的变化范围是3345~1207 Ω?cm,4038~3643 K。(3) 采用氧化物固相反应法制备了单相BaSn1-ySbyO3 (0≤y≤0.5)和Ni0.66Nn2.34O4氧化物粉体材料。结合TG/DSD确定了BaSn1-ySbyO3 (0≤y≤0.5)粉体的最佳煅烧温度为1200 ℃。烧结后的复合陶瓷材料主要由立方尖晶石和立方钙钛矿相结构组成,复合材料中钙钛矿相的复合量、Sb的掺杂量都对复合陶瓷材料的微观结构和形貌产生一定程度的影响。(4) 研究发现(BaSn1-ySbyO3)x(Ni0.66Mn2.34O4)1-x (0≤x≤0.5,0≤y≤0.5)的电阻率和B值都随着钙钛矿相和Sb含量的增加而增大。当y=0时,随x从0增加到0.4,复合材料的电阻率从4123 Ω?cm增加到40620 Ω?cm,B值从3962 K增加到4281 K。当x=0.2时,复合材料的室温电阻率和B值的变化范围分别是11.52~30.52 KΩ?cm和4220~4656 K。
英文摘要NTC( Negative Temperature Coefficien) thermistor materials are widely used for temperature sensors, temperature compensation devices, metallic thermocouples, semi-conductive ceramics, and suppression of in-rush current, owing to their various advantages, including high sensitivity, fast response, small volume and low cost. The transition metal elements( Mn, Ni, Co, Cu, etc) based single spinel oxides of generally formula AB2O4 is one of the most commonly used NTC thermistor. The range of the application temperature of this material is relatively narrow, the sintered spinel structure ceramics is in a non-equilibrium state due to defects nonuniform distribution, which results in a change of electrical properties, and the thermal stability is poor when used in medium temperature area. Therefore, exploring a new NTC thermistor material with wide using temperature area, high stability thermistor materials is of great significance. As a kind of material with a great development prospect, composite material played an important role in the research of change of material performance. Due to the product effect and additive property composite material, the microstructure and performance of materials can be controlled, thus the outstanding and attractive proformance can be obtained that the single component couldn’t achieve.This paper applied complexing and doping technology into traditional spinel structure, and studied the (LaMn1-yCoyO3)x-(Ni0.66Mn2.34O4)1-x (0≤x≤0.5, 0≤y≤0.5) and (BaSn1-ySbyO3)x(Ni0.66Mn2.34O4)1-x (0≤x≤0.5, 0≤y≤0.5) composite material system. The performance of powder and ceramics samples were characterized and analyzed by TG/DSC, DIL, XRD, SEM, EDS and electrical measurement to study the effect of multiplicity and doping content and the process conditions on the microstructure and electric properties of the composites, and discusses the conductive mechanism of the composite. This thesis can be summarized as follows:(1) The LaMn1-yCoyO3 (0≤y≤0.5) and Ni0.66Mn2.34O4 samples were prepared by conventional solid-state reaction synthesis method. The optimum calcined temperature of LaMn1-yCoyO3 (0≤y≤0.5) and Ni0.66Mn2.34O4 are determined by XRD analysis,which are 1000 ℃ and 950 ℃,respectively. The sintered composite ceramics consist of a cubic spinel phase structure and an orthogonal perovskite phase structure. Both of the relative content of the perovskite phase and the Co doping content affect the microstructure and morphology of a certain degree of influence.(2) When y=0.5, both of the resistivity and material constant B value of the composite ceramic materials are decreased with the increasing of LaMn0.5Co0.5O3 content, the room temperature resistivity ρ25 and material constant B are in the range of 4767~ 20 Ω?cm and 3970~ 1573 K, respectively. The relative resistance drift (△R/R0) for the composites after aging test at 125 ℃ for 1000 h in air atmosphere decrease significantly with increasing LaMn0.5Co0.5O3 content, as the x increases from 0 to 0.5, the △R/R0 of the composites decreases from 1.8 % to 0.28 %, indicating the stability of composite is improved. When x=0.2, the resistivity of the composite decreases with increasing of Co doping content, the range of the ρ25 and B25/50 are 3345 ~ 3345 Ω?cm, and 4038 ~ 3643 K, respectively.(3) The BaSn1-ySbyO3 (0≤y≤0.5) samples were prepared by solid-state reaction synthesis method. The optimum calcined temperature of BaSn1-ySbyO3 (0≤y≤0.5) is determined by TG/DSC analysis,which is 1200 ℃. The sintered composite ceramics consist of a cubic spinel phase structure and a cubic perovskite phase structure. Both of the relative content of the perovskite phase and the Sb doping content affect the microstructure and morphology.(4) It is found that both of the resistivity and material constant B value of the (BaSn1-ySbyO3)x(Ni0.66Mn2.34O4)1-x (0≤x≤0.5,0≤y≤0.5) composite ceramic materials are increased with the increasing of pervoskite content and Sb doping content. When y=0, as the x increase from 0 to 0.4, the room temperature resistivity ρ25 of the composites increases from 4123 Ω?cm to 40620 Ω?cm as the x increases from 0 to 0.4, while the B25/50 increases from 3962 K to 4281 K. When x=0.2, the resistivity of the composite decreases with increasing of Sb doping content, the range of the ρ25 and B are 3345~ 3345 Ω?cm, and 4038~ 3643 K, respectively.
内容类型学位论文
源URL[http://ir.xjipc.cas.cn/handle/365002/4587]  
专题新疆理化技术研究所_材料物理与化学研究室
作者单位中国科学院新疆理化技术研究所
推荐引用方式
GB/T 7714
黄翠萍. 复合NTC 热敏电阻材料La(Mn, Co)O3/Ba(Sn, Sb)O3-Ni0.66Mn2.34O4的制备与电性能研究[D]. 北京. 中国科学院大学. 2016.
个性服务
查看访问统计
相关权益政策
暂无数据
收藏/分享
所有评论 (0)
暂无评论
 

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。


©版权所有 ©2017 CSpace - Powered by CSpace