摘要
采用氧化物粉末固相烧结法制备Pb(Ni_(1/3)Nb_(2/3))0.5(Zr_(0.3)Ti_(0.7))0.5O_3–w Co_2O_3(0.5PNN–0.5PZT–w Co)压电陶瓷。研究了Co_2O_3掺杂含量对0.5PNN–0.5ZT压电陶瓷相结构、显微组织、电学性能及介电弛豫的影响。结果表明:Co^(3+)掺杂进入主晶体结构中占据了B位。当0.2%≤w≤0.8%(质量分数)时,样品为单一稳定的钙钛矿结构,存在准同型相界;通过修正Curie–Weiss定律,较好地描述了陶瓷弥散相变的特征,弥散相变系数γ随着Co_2O_3掺杂量的增加,先增加后减小,当w=0.4%时,γ达到最大值,表明样品的介电弛豫特征更为明显。样品具有最佳的综合电学性能,压电常数d33=675 p C/N,机电耦合系数kp=60%,介电常数εr和介电损耗tanδ分别约为5 765和1.16%,说明介电弛豫行为与电学性能相关。
Pb（Ni1/3Nb2/3）0.5（Zr0.3Ti0.7）0.503-xCo203（O.5PNN-0.5PZT-xCo） piezoelectric ceramics were prepared by a solid state reaction method. The effect of Co203 doping on the phase structure, electrical properties and dielectric relaxation of 0.5PNN-0.5PZT ceramics were investigated. The results show that Co3＋ occupies the B-site. According to the results by X-ray diffraction, all the ceramics prepared with content of Co203 from 0.2% （in mass fraction） to 0.8% are a single perovskite phase and possess a morphotropic phase boundary （MPB）. A modified Curie-Weiss law can describe the diffuseness of phase transition properly when Co addition increases. The dispersion coefficient of phase transformation y firstly increases and then decreases. When x = 0.4%, y reaches a maximum, indicating that the dielectric relaxation behavior of ceramic is more evident. The ceramic with the Co203 content of 0.4% exhibits the optimum properties, i.e., d33 = 675 pC/N, kp = 60%, εr is 5 765, and tanδ is 1.16%, showing that the dispersion of phase transformation connects with the electrical properties to some extent.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2016年第3期380-386,共7页
Journal of The Chinese Ceramic Society
基金
贵州省工业攻关项目[黔科合GY字(2013)3075]资助
关键词
氧化钴掺杂
介电弛豫
电学性能
cobaltous oxide doping
dielectric relaxation
electrical properties
