How to optimize the microstructure of multiferroic materials, and multiferroic material structures

摘要

PROBLEM TO BE SOLVED: To provide a method for optimizing a microscopic structure of a multiferroic material capable of obtaining a new microscopic structure capable of obtaining a larger macroscopic material property value, and a multiferroic material structure based on the method. SOLUTION: A unit cell model of a microscopic structure composed of a piezoelectric phase and a magnetic phase is constructed, and a microscopic structure and a macroscopic structure formed by periodically and repeatedly arranging the microscopic structure are used. In the method of optimizing the microstructure of multiferroic materials, which formulates the coupling of two scales and obtains numerical solutions to the obtained partial differential equations of both scales by the finite element method, the macroscopic material property values are obtained. Using the microscopic structure as a variable and the microscopic structure as a variable, a calculation process is performed to maximize the macroscopic material property value by sequentially changing the microscopic structure using an extreme value search method. [Selection diagram] FIG. 5