Piezoelectric Material Near Morphotropic Phase Boundary
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current piezoelectric materials have a low piezoelectric effect, limiting their extensive application in touch-controlled reproduction devices due to their intrinsic properties.
Innovation Solution
A piezoelectric material with a perovskite structure near a morphotropic phase boundary, doped with elements that increase the difference between the lattice constants of coexisting rhombohedral and tetragonal structures, enhancing the material's piezoelectricity and strain properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional piezoelectric materials are used, then the device structure is simple, but the piezoelectric effect is low which limits tactile reproduction effectiveness
Solution Approach 1:
The patent changes the crystallographic parameters by positioning the material near a morphotropic phase boundary where rhombohedral and tetragonal phases coexist. This parameter change in the crystal structure enables a significantly enhanced piezoelectric effect compared to conventional single-phase piezoelectric materials
Solution Approach 2:
The patent employs a composite material system with a perovskite matrix containing coexisting rhombohedral and tetragonal phases. This composite phase structure leverages the synergistic effects of both phases to achieve superior piezoelectric performance
2Reliability
If doping elements are added to enhance piezoelectricity, then the piezoelectric effect increases, but the material composition becomes more complex
Solution Approach 1:
The patent applies local quality by introducing doping elements at specific lattice positions (A-site or B-site substitutions) within the perovskite structure. This localized modification at specific crystallographic sites enables enhanced piezoelectricity while maintaining the overall perovskite framework structure
Solution Approach 2:
The doping elements modify the lattice parameters and phase stability of the perovskite structure, enabling the material to maintain the coexistence of rhombohedral and tetragonal phases near the morphotropic phase boundary, thereby enhancing piezoelectric effect
3Reliability
If the lattice constant difference between rhombohedral and tetragonal structures is increased, then the intrinsic strain increases, but the crystal structure stability may be compromised
Solution Approach 1:
The patent optimizes the lattice constant difference between rhombohedral and tetragonal phases by carefully controlling the composition near the morphotropic phase boundary and selecting appropriate doping elements. This parameter optimization achieves maximum intrinsic strain while maintaining crystal structure stability through the cooperative stabilization of both phases
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The enhanced piezoelectric material improves the amplitude of tactile sensation and the effectiveness of tactile reproduction by increasing the intrinsic strain and facilitating efficient conversion between electric and mechanical energy.
Implementation Method 1
tactile-reproduction devices based on piezoelectric materials may regulate the friction of the surface of the substrate via the resonance generated between the piezoelectric-material layer and the substrate
Data Source
AI summary
A piezoelectric material and a piezoelectric device. The piezoelectric material includes: a matrix, wherein a crystal structure of the matrix is an ABO3-type perovskite structure, the perovskite structure includes a rhombohedral structure and a tetragonal structure that coexist, and the matrix is near a morphotropic phase boundary; and a doping element, wherein the doping element is for replacing an A-site element or a B-site element in the perovskite structure, or filling a space in the perovskite structure, and the doping element is for increasing a difference between a lattice constant of the rhombohedral structure and a lattice constant of the tetragonal structure.