MgB2 Superconducting Wire Dual-Core Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing MgB2 superconducting wires struggle to achieve both high critical current density (Jc) and long-length uniformity, with deformation and voids in the wire-drawing process leading to non-uniform conduction characteristics and reduced current density.
Innovation Solution
The solution involves a dual-core structure for the MgB2 superconducting wire, with a high-density MgB2 core and a low-density MgB2 core, where the high-density core is filled with strongly mixed powder and the low-density core with weakly mixed powder, enhancing the wire's cross-sectional uniformity and stability during the wire-drawing process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If mechanical milling is used to improve initial filling rate, then critical current density improves, but manufacturing complexity increases
Solution Approach 1:
The core is divided into two distinct regions: a central high-density region and an outer low-density region. This segmentation allows each region to serve different functions - the high-density region provides structural integrity and high critical current density, while the low-density region facilitates easier wire drawing and reduces deformation. By segmenting the core structure, the patent achieves both high performance and manufacturing feasibility without requiring complex mechanical milling processes.
Solution Approach 2:
Different regions of the core are given different density characteristics. The central region has high density (0.65-0.75 g/cm³) to maximize critical current density, while the outer region has lower density (0.55-0.65 g/cm³) to reduce deformation during wire drawing. This local differentiation of quality allows the wire to simultaneously achieve high electrical performance and manufacturing ease, resolving the contradiction between critical current density and manufacturing complexity.
2Manufacturing precision
If high filling rate is achieved through mechanical milling, then critical current density improves, but wire deformation increases during drawing
Solution Approach 1:
The core is divided into two distinct regions: a central high-density region and an outer low-density region. This segmentation allows each region to serve different functions - the high-density region provides structural integrity and high critical current density, while the low-density region facilitates easier wire drawing and reduces deformation. By segmenting the core structure, the patent achieves both high performance and manufacturing feasibility without requiring complex mechanical milling processes.
Solution Approach 2:
The patent changes the density parameter across different regions of the core. The central region maintains high density (0.65-0.75 g/cm³) for optimal critical current density, while the outer region uses lower density (0.55-0.65 g/cm³) to reduce deformation during wire drawing. This parameter differentiation resolves the contradiction between achieving high filling rate for critical current density and minimizing wire deformation during the drawing process.
3Ease of manufacture
If uniform density is maintained throughout the core, then manufacturing is simplified, but critical current density uniformity over long length deteriorates
Solution Approach 1:
The core is divided into two distinct regions: a central high-density region and an outer low-density region. This segmentation allows each region to serve different functions - the high-density region provides structural integrity and high critical current density, while the low-density region facilitates easier wire drawing and reduces deformation. By segmenting the core structure, the patent achieves both high performance and manufacturing feasibility without requiring complex mechanical milling processes.
Solution Approach 2:
Different regions of the core are given different density characteristics. The central region has high density (0.65-0.75 g/cm³) to maximize critical current density, while the outer region has lower density (0.55-0.65 g/cm³) to reduce deformation during wire drawing. This local differentiation of quality allows the wire to simultaneously achieve high electrical performance and manufacturing ease, resolving the contradiction between critical current density and manufacturing complexity.
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
This approach results in a wire with high conduction characteristics uniformly maintained over its entire length, preventing deformation and disconnection, and improving critical current density by up to 15% compared to conventional methods.
Implementation Method 1
volume shrinkage occurs in the reaction of Mg+2B→MgB2
Implementation Method 2
mechanical milling of raw material powder is effective. Powders of Mg and B and a metal ball are put in a metal container and rotated at a high speed using a planetary ball mill apparatus
Implementation Method 3
there is almost no void between powder particles, thus the initial filling rate becomes a value close to 100%
Data Source
AI summary
An MgB2 superconducting wire includes a core containing MgB2 and a metal sheath which surrounds the core. The core includes at least a first MgB2 core positioned on the center side, and a second MgB2 core positioned outside the first MgB2 core, and the density of the second MgB2 core is lower than the density of the first MgB2 core.