Sheet-type micro refrigerator applying lead-free ferroelectric material

Abstract

The invention relates to a sheet-type micro refrigerator applying a lead-free ferroelectric material. The micro refrigerator comprises a multi-layer structure which is composed of a ferroelectric dialectric layer and a metal electrode layer alternatively; the ferroelectric dielectric layer is made of the lead-free ferroelectric material; periodic square wave signals with alternative changes of working electric fields for controlling the ferroelectric dialectric layer are applied on the metal electrode layer, thus the changes of the working electric fields of the ferroelectric dialectric layerare higher than 100kv/cm. A curtain coating technology is adopted to manufacture the multi-layer thick film structure for the sheet-type micro refrigerator provided by the invention, the high electrocaloric effect is realized through a superelevation electric field condition, and the sheet-type micro refrigerator has the following beneficial effects: 1) environmental protection: a lead-free ferroelectric ceramic is adopted as a working medium, which correponds to the environment protection requirement; 2) high efficiency: the actual refrigerating amount can reach more than 2J/g; and 3) the structure is simple, the production technology is mature, and the cost is low. 本发明涉及一种应用无铅铁电材料的片式微制冷器，其包括铁电介质层与金属电极层交替构成的多层结构，所述铁电介质层采用无铅铁电材料；所述金属电极层上施加有用于控制所述铁电介质层的工作电场交替变化的周期方波信号，使铁电介质层工作电场的变化高于100kV/cm。本发明的片式微制冷器采用流延工艺制备多层厚膜结构，通过超高电场条件实现了高电热效应，并具有以下有益效果：1)环保：采用无铅铁电陶瓷为工作介质，符合环保要求；2)高效：实际制冷量可达2J/g以上；3)结构简单、生产工艺成熟、成本低廉。