Electrical Steel Insulating Coating With P-Concentrated Adhesion Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional technologies fail to ensure sufficient adhesion between a steel sheet and an insulating coating when the thickness of the insulating coating is reduced, leading to a decrease in the stacking factor of electrical steel sheets.
Innovation Solution
Concentrating phosphorus (P) on both the surface side and interface side with the steel substrate of the insulating coating, forming P-concentrated layers to enhance adhesion, which can be achieved by using a rolling oil with a phosphoric ester-type emulsifier, applying an aqueous phosphoric acid compound solution, or subjecting the slab to high-temperature annealing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the thickness of the insulating coating is reduced, then the stacking factor is improved, but the adhesion between the steel sheet and the insulating coating deteriorates
Solution Approach 1:
The patent applies local quality by creating P-concentrated layers at specific locations within the insulating coating (at the interface with the steel sheet and at the surface) rather than uniformly distributing phosphorus throughout the coating. This localized concentration of P at critical interfaces maintains adhesion even when the overall coating thickness is reduced, while the reduced thickness improves the stacking factor.
2Loss of energy
If the thickness of the insulating coating is reduced, then the iron loss is reduced, but the adhesion between the steel sheet and the insulating coating deteriorates
Solution Approach 1:
The patent uses local quality by concentrating phosphorus at specific locations (interface and surface) rather than uniformly throughout the coating. This allows the coating to be thinner (reducing iron loss) while maintaining adhesion through the localized P-concentrated layers that strengthen the coating structure and bonding at critical interfaces.
3Loss of energy
If the thickness of the electrical steel sheet is reduced, then the iron loss in high-frequency ranges is reduced, but the stacking factor decreases
Solution Approach 1:
The patent applies parameter changes by modifying the chemical composition and concentration distribution of phosphorus within the insulating coating. By controlling the P concentration to be higher at the interface and surface regions, the coating maintains its adhesive function at reduced thickness, thereby improving the stacking factor while allowing the steel sheet thickness to be reduced for lower iron loss.
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 electrical steel sheet maintains excellent adhesion of the insulating coating even with reduced thickness, thereby improving the stacking factor and reducing iron loss.
Implementation Method 1
subjecting the slab to final annealing at 1100° C. or higher
Implementation Method 2
using a rolling oil containing a phosphoric ester-type emulsifier at a concentration of 1% or more as a rolling oil in final cold rolling to adhere P to the surface of the steel sheet
Data Source
AI summary
Provided is a non-oriented electrical steel sheet having excellent adhesion with an insulating coating even if the thickness of the insulating coating is reduced. The non-oriented electrical steel sheet of the present disclosure has an insulating coating on at least one surface of the steel sheet, where the insulating coating has a P-concentrated layer on both a surface side and an interface side with a steel substrate, and a P concentration of the P-concentrated layer is higher than a P concentration in the steel substrate.