Sodium bismuth titanate-based relaxor ferroelectric ceramic material with wide temperature range, high electrocaloric effect and low field and high electrocaloric strength and preparation method of sodium bismuth titanate-based relaxor ferroelectric ceramic material

Abstract

The invention relates to a sodium bismuth titanate-based relaxor ferroelectric ceramic material with wide temperature range, high electrocaloric effect and high electrocaloric strength and a preparation method of the sodium bismuth titanate-based relaxor ferroelectric ceramic material, wherein the ceramic material conforms to a chemical general formula (Bi0.5Na0.44-xK0.06+x)0.92Sr0.08Ti0.99Nb0.01O3. The preparation method comprises the following steps: according to the chemical general formula,mixing the raw materials, and sequentially carrying out primary ball milling, discharging, drying, presintering, secondary ball milling, granulation, compression molding, rubber discharging and sintering to obtain the ceramic material. Compared with the prior art, the novel sodium bismuth titanate-based relaxor ferroelectric ceramic material provided by the invention is used as a lead-free material, and the ceramic electrocaloric refrigeration material meets the requirements of environmental protection and has the advantages of low preparation cost and good stability; and the high electrocaloric effect and the wide-temperature-range high electrocaloric effect under the low electric field have huge application prospects in the aspect of solid refrigeration.

Description

technical field [0001] The invention belongs to the technical field of electronic functional materials and devices, and relates to a novel bismuth sodium titanate-based relaxor ferroelectric ceramic material with a wide temperature range, high electric card effect and high electric card strength and a preparation method thereof, in particular to a ( Bi 0.5 Na 0.44- x K 0.06+x ) 0.92 Sr 0.08 Ti 0.99 Nb 0.01 o 3 Electric card effect of lead-free relaxor ferroelectric ceramics and its preparation method. Background technique [0002] Traditional air-conditioning and refrigeration systems are designed according to the theory of compressor refrigeration and rely on refrigerants such as freon or chlorofluorocarbons (CFCs) to drive. When the refrigerant volatilizes into the atmospheric ozone layer, it can catalyze the reaction of ozone, which greatly reduces the ultraviolet radiation barrier ability of the ozone layer. In order to reduce the damage to the ozone layer, peo...

AI Technical Summary

Problems solved by technology

[0004] Chinese patent CN201410474671.1 discloses a method for improving the performance of dielectric electric card ceramic refrigeration equipment. The patent uses BaTiO 3 and bismuth-based PbTiO 3 The electric card device was obtained by forming a multi-layer structure, but this patent is only the design method of the electric card refrigeration device, and there is no breakthrough research from the perspective of a single material, and there is no actual test to measure the temperature change and strength of the electric card. Moreover, the materials involved contain lead, which is harmful to the human body. The bismuth sodium titanate-based relaxor ferroelectric ceramic refrigeration material in this application is an environmentally friendly lead-free material, and there is no pollution during the process of production, use, and disposal. Moreover, the temperature change of the electric card in this application is all based on the high-sensitivity thermal resistance test method, and the accuracy is high.

Images