R-Fe-B Sintered Magnet Plating via Barrel Ultrasonic Cleaning

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for forming a plating film on R-Fe-B based sintered magnets face challenges in achieving adhesiveness due to oxide or hydroxide film formation, especially with highly alkaline plating baths, and require troublesome magnet transfer during smut removal processes.

Innovation Solution

Conducting acid cleaning and smut removal as pretreatments in a synthetic resin barrel without transferring the magnet, using ultrasonic cleaning in degassed water with reduced oxygen levels (0.1-6 ppm) and a specific oscillation frequency (20 kHz to 100 kHz), followed by plating treatment, allowing for a plating film with enhanced adhesiveness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If magnet is transferred from mesh basket to barrel for plating after acid cleaning and ultrasonic cleaning, then smut removal can be conducted, but the process becomes troublesome and requires multiple transfer operations

Engineering Contradiction:
Improvesmut removal effectivenessVSAvoidprocess simplicity
Core Design Contradiction:
Manufacturing precisionVSEase of operation

Solution Approach 1:

The invention merges all pretreatment steps (acid cleaning and smut removal) into a single barrel, eliminating the need for multiple transfers between different equipment. By combining these functions in one location, the invention significantly simplifies the operational process while maintaining effective smut removal

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The barrel is designed to perform multiple functions: it serves as both the acid cleaning container and the smut removal vessel. This multi-functionality eliminates the need for separate mesh baskets and multiple transfer operations, making the overall process more efficient and easier to operate

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 method effectively forms a plating film with excellent adhesiveness on R-Fe-B based sintered magnets, preventing rust and maintaining magnetic characteristics without the need for magnet transfer, even with highly alkaline plating baths.

Implementation Method 1

the smut removal is conducted by ultrasonic cleaning of the magnet with rotating the barrel in water in which the dissolved oxygen amount is set to 0.1 ppm to 6 ppm by degassing

Methodology Applied
Scientific EffectUltrasonic cavitation: Cavitation

Implementation Method 2

a plating treatment is conducted to the magnet after the smut removal, and a plating film is formed on the surface

Methodology Applied
Scientific EffectElectrolysis: Electrolysis

Data Source

PatentEP2677065B1Production method for r-fe-b sintered magnet having plating film on surface thereof
Publication Date: 2018.06.20 PROTERIAL LTD
  • EP2677065B1 patent drawingFigure 1
  • EP2677065B1 patent drawingFigure 2

AI summary

An object of the present invention is to provide a production method for an R-Fe-B based sintered magnet having a plating film excellent in adhesiveness on the surface thereof, by conducting a series of processes of acid cleaning and smut removal as pretreatments of a plating treatment of an R-Fe-B based sintered magnet, and the subsequent plating treatment, effectively without requiring troubles. The production method for an R-Fe-B based sintered magnet having a plating film on the surface thereof of the present invention, as a solution method therefor, is characterized in that a series of processes of acid cleaning and smut removal of a magnet as pretreatments of a plating treatment, and the subsequent plating treatment is conducted consistently with a state, in which the magnet is placed in a barrel made of synthetic resin, and that the smut removal is conducted by ultrasonic cleaning of the magnet with rotating the barrel in water in which the dissolved oxygen amount is set to 0.1 ppm to 6 ppm by degassing.