Resistance Welding Contact Geometry to Reduce Plating Adhesion

Solution Overview

Problem

Resistance welding of metal steel plates with plated surfaces often results in plating adhesion to electrodes, leading to increased welding defects and reduced electrode life due to the accumulation of adhered plating, which existing techniques fail to adequately address.

Innovation Solution

The method involves forming curved contact areas on the plate materials along the contours of the electrodes, ensuring a large and stable contact area, reducing the likelihood of plating adhesion and minimizing changes in resistance values during repeated welding, thereby extending electrode life.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If resistance welding is performed on plate materials with plated surfaces, then welding joining is achieved, but plating adheres to electrodes and welding defects occur

Engineering Contradiction:

Improvewelding qualityVSAvoidplating adhesion to electrode

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent applies preliminary action by using an initial current before the main welding current to soften the plating layer in advance. This preliminary softening prevents plating adhesion during subsequent welding operations, solving the problem of plating adhering to electrodes while maintaining welding quality

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes the electrical parameter by applying a two-stage current process: first an initial current at a lower level to soften plating, then a main welding current at a higher level to create the nugget. This parameter change approach prevents plating adhesion while ensuring proper welding

Inventive Principle:

Principle #35Parameter changes

2Object-generated harmful factors

If initial current is used to soften plating layer, then plating adhesion is reduced, but plating cannot be completely eliminated and adhesion may not be sufficiently reduced

Engineering Contradiction:

Improveplating adhesionVSAvoidelectrode life

Core Design Contradiction:

Object-generated harmful factorsVSReliability

Solution Approach 1:

The patent applies preliminary action by using an initial current before the main welding current to soften the plating layer in advance. This preliminary softening prevents plating adhesion during subsequent welding operations, solving the problem of plating adhering to electrodes while maintaining welding quality

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes the electrical parameter by applying a two-stage current process: first an initial current at a lower level to soften plating, then a main welding current at a higher level to create the nugget. This parameter change approach prevents plating adhesion while ensuring proper welding

Inventive Principle:

Principle #35Parameter changes

3Productivity

If welding is performed repeatedly with the same electrode, then productivity is maintained, but plating accumulation increases and welding defects occur

Engineering Contradiction:

Improvewelding speedVSAvoidwelding quality

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies preliminary action by using an initial current before the main welding current to soften the plating layer in advance. This preliminary softening prevents plating adhesion during subsequent welding operations, solving the problem of plating adhering to electrodes while maintaining welding quality

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes the electrical parameter by applying a two-stage current process: first an initial current at a lower level to soften plating, then a main welding current at a higher level to create the nugget. This parameter change approach prevents plating adhesion while ensuring proper welding

Inventive Principle:

Principle #35Parameter changes

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 reduces welding defects and prolongs electrode life by maintaining a consistent contact area and heat generation, even with aluminum plating, and is effective for both pre- and post-quenching steel plates.

Implementation Method 1

applying resistance welding to the workpiece

Methodology Applied

Scientific EffectJoule heating: Joule Heating

Data Source

PatentUS11590600B2Manufacturing method of joined member

Publication Date: 2023.02.28 FUTABA IND CO LTD

AI summary

Provided is a method of manufacturing a joined member that is manufactured by applying resistance welding to a workpiece. The workpiece is provided with plating layers on sides to be in contact with electrodes. In a state in which a first electrode is in contact with a first area in a first plate material that is curved along a contour of a leading end of the first electrode and in which a second electrode is in contact with a second area in a second plate material that is curved along a contour of a leading end of the second electrode, energization between the first electrode and the second electrode is started to form a nugget.