Iron Nitride Magnet Casting With Applied Field Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current permanent magnets rely heavily on rare earth elements, which are scarce and expensive, and their production contributes to environmental deterioration and high manufacturing costs, due to processes like crushing, compressing, and sintering at high temperatures.
Innovation Solution
The development of techniques for forming iron nitride magnetic materials with uniaxial magnetic anisotropy, such as α″-Fe16N2, through casting and consolidation in an applied magnetic field, which aligns crystal orientations and increases magnetic anisotropy, reducing the need for rare earth elements and lowering production costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If rare earth elements are used to produce permanent magnets, then high energy product is achieved, but manufacturing cost increases and environmental deterioration occurs
Solution Approach 1:
The patent replaces expensive rare earth elements with abundant, inexpensive iron-based materials. The iron nitride magnets use common materials (iron, nitrogen) instead of scarce rare earth elements like neodymium, achieving comparable magnetic performance while dramatically reducing material cost and eliminating the need for expensive crushing, compressing, and sintering processes.
2Reliability
If rare earth elements are used in permanent magnets, then high energy product is achieved, but supply shortages and price increases occur
Solution Approach 1:
The invention substitutes scarce rare earth elements with abundant iron and nitrogen. Iron is one of the most abundant elements in the Earth's crust, and nitrogen is readily available from the atmosphere. This substitution ensures long-term supply security and price stability while maintaining high magnetic energy product through the formation of iron nitride phases with uniaxial magnetic anisotropy.
3Ease of manufacture
If conventional sintering process is used for magnet fabrication, then permanent magnets are formed, but high manufacturing cost and environmental impact result
Solution Approach 1:
The patent fundamentally changes the manufacturing parameters by eliminating the high-temperature sintering process (typically over 1000°C) required for conventional rare earth magnets. Instead, the invention uses lower-temperature processing methods to form iron nitride magnets, significantly reducing energy consumption and environmental impact while maintaining magnetic performance.
Solution Approach 2:
The invention replaces the mechanical crushing and compressing steps with a chemical synthesis approach. Rather than mechanically processing rare earth materials, the patent uses chemical reactions between iron and nitrogen to directly form the magnetic iron nitride phase, eliminating dust generation and mechanical wear while reducing overall 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
These techniques produce bulk permanent magnets with high saturation magnetization and magnetic anisotropy constants, achieving an energy product comparable to rare earth magnets while reducing environmental impact and production costs.
Implementation Method 1
By applying a magnetic field during the casting process, the nucleation and grown of iron nitride crystals may be influenced such that growth of crystals having a predetermined orientation may be energetically favorable
Implementation Method 2
iron nitride crystals having (002) or (004) crystal planes substantially parallel to the direction of the applied magnetic field may be more energetically favorable
Implementation Method 3
a magnetic field may be applied to the material being consolidated to substantially align magnetic easy axes of multiple workpieces including at least one iron-based phase domain including uniaxial magnetic anisotropy
Implementation Method 4
magnetic easy axes of multiple workpieces including at least one iron-based phase domain including uniaxial magnetic anisotropy may be aligned substantially parallel to the direction of the applied magnetic field
Data Source
AI summary
Techniques are disclosed concerning applied magnetic field synthesis and processing of iron nitride magnetic materials. Some methods concern casting a material including iron in the presence of an applied magnetic field to form a workpiece including at least one iron-based phase domain including uniaxial magnetic anisotropy, wherein the applied magnetic field has a strength of at least about 0.01 Tesla (T). Also disclosed are workpieces made by such methods, apparatus for making such workpieces and bulk materials made by such methods.