Ni-P-B Plating Film Hardness Without Baking

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current deposition methods for Ni—P—B system plating films face challenges in achieving high hardness while maintaining manufacturing efficiency, often requiring baking processing and risking poor appearance issues like 'burning' due to limited current density in electroplating.

Innovation Solution

Increasing the concentration of alkylamine borane and acetic acid in the plating bath within specific ranges during electroplating, combined with the use of primary and secondary brightening agents, including surface active agents, allows for higher current density without 'burning' or abnormal precipitation, enabling high hardness and efficient film formation without baking.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If current density is increased to improve film forming rate, then manufacturing efficiency is improved, but poor appearance such as burning occurs

Engineering Contradiction:
Improvefilm forming rateVSAvoidappearance quality
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The invention changes the chemical composition parameters of the plating bath by adding alkylamine borane and acetic acid in specific concentrations. This parameter change allows the system to tolerate higher current densities without producing burning defects, thus resolving the contradiction between productivity and appearance quality

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

Alkylamine borane acts as an intermediary substance that mediates between the high current density and the plating film formation. It prevents the direct harmful effect of high current density (burning) while allowing the beneficial effect (high film forming rate) to continue

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If non-electrolytic plating is used to deposit plating film, then corrosion resistance is improved, but film forming rate becomes very slow

Engineering Contradiction:
Improvecorrosion resistanceVSAvoidfilm forming rate
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The invention replaces the chemical reaction mechanism of non-electrolytic plating with an electrochemical deposition mechanism. This substitution enables much higher film forming rates while maintaining the protective corrosion resistance properties through controlled electrolytic deposition

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Manufacturing precision

If baking processing is performed to improve hardness and adhesion, then film quality is improved, but manufacturing efficiency decreases

Engineering Contradiction:
Improvehardness and adhesionVSAvoidmanufacturing efficiency
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The invention extracts and eliminates the baking processing step from the manufacturing process. By modifying the plating bath composition to produce films with inherently high hardness and adhesion, the separate heat treatment step becomes unnecessary, thus improving manufacturing efficiency while maintaining film quality

Inventive Principle:
Principle #2Taking out (Extraction)

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 Ni—P—B system plating films with high hardness and improved abrasion resistance, fatigue strength, and sliding characteristics, while eliminating the need for baking processing, thus enhancing manufacturing efficiency and film forming rate.

Implementation Method 1

electroplating is performed in a plating bath containing Ni ions, phosphorous acid ions, alkylamine borane, acetic acid, at least one sort of a primary brightening agent, and a secondary brightening agent

Methodology Applied
Scientific EffectElectroplating: Electroplating

Data Source

PatentUS11193215B2Deposition method of Ni—P—B system electroplating film, the film, and slide member comprising the film
Publication Date: 2021.12.07 AISIN SEIKI KK

AI summary

In a deposition method of Ni—P—B system plating film, electroplating is performed in a plating bath containing Ni ions, phosphorous acid ions, alkylamine borane, acetic acid, at least one sort of a primary brightening agent, and a secondary brightening agent including at least one sort of a surface active agent. In the above-mentioned plating bath, concentration of alkylamine borane in said plating bath is 1.37 mmol/L or more, and concentration of acetic acid in said plating bath is 0.70 mol/L or more and less than 2.80 mol/L. Thereby, plating film having high hardness of Hv 700 or more can be deposited with high manufacturing efficiency without baking processing, while reducing occurrence of poor appearance, such as burning and abnormal precipitation, even when current density is increased to 80 A/dm2 or more to raise deposition rate.