Recessed Laser-Marked Metal Codes for Shot Blast Resistance

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for identifying metal workpieces are prone to errors due to the risk of misidentification when metal castings are manipulated between the die-casting and identification stations, especially when shot blasting can damage or erase previously marked identifiers, compromising tracking accuracy.

Innovation Solution

Implementing a laser-marking system that creates shot-blast resistant identifiers by recessing the surface of metal workpieces with a laser, forming dark cells that remain readable after shot blasting through precise removal of metal at the center portion, leaving a recess bounded by a peripheral wall with specific depth and width ratios.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If traditional marking methods are used to identify metal workpieces early in the production line, then identification accuracy is improved, but the identifier is damaged or erased by subsequent shot blasting

Engineering Contradiction:

Improveidentification accuracyVSAvoididentifier durability

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The laser marking is performed early in the production line before shot blasting, establishing the identifier in advance. The marking is done on the as-cast surface, and the identifier is designed to withstand the subsequent shot blasting process through proper laser parameters and marking depth control.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The laser marking parameters (power, pulse duration, frequency, scan speed) are optimized to create an identifier that is readable immediately but resistant to shot blasting. The marking depth and surface modification are controlled to achieve both early readability and durability through the shot blasting process.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If laser marking is performed to create durable identifiers, then identifier durability is improved, but the marking complexity and process time increase

Engineering Contradiction:

Improveidentifier durabilityVSAvoidlaser-marking process complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The laser marking is applied selectively only to the areas that need to form the identifier (dark cells), rather than treating the entire surface. The marking depth and intensity are optimized to achieve sufficient durability without excessive material removal or complex multi-pass processing.

Inventive Principle:

Principle #16Partial or excessive action

3Loss of information

If early identification is implemented to reduce manipulation errors, then tracking accuracy is improved, but the identifier must withstand shot blasting which damages traditional marks

Engineering Contradiction:

Improvetracking accuracyVSAvoidshot blasting damage

Core Design Contradiction:

Loss of informationVSObject-affected harmful factors

Solution Approach 1:

The shot blasting process, which is harmful to traditional surface marks, is converted into a beneficial process for the laser-marked identifier. The laser-marked cells (particularly the dark cells with modified surface properties) become more resistant to shot blasting, and the process actually enhances the contrast and durability of the identifier while leaving it readable.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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

Ensures accurate identification and tracking of metal workpieces even after shot blasting, reducing the likelihood of misidentification and maintaining identifier legibility by creating a durable laser-marked code that withstands the shot blasting process.

Implementation Method 1

laser-marking the identifier on a surface of the received metal workpiece by laser-removing metal from the surface of the metal workpiece

Methodology Applied

Scientific EffectLaser ablation: Laser Ablation

Data Source

PatentUS11738409B2Metal workpieces with shot blast resistant identifiers, methods and systems for laser-marking such identifiers

Publication Date: 2023.08.29 LASERAX

AI summary

There is described a metal workpiece generally having a surface and an identifier marked on said surface. The identifier has cells each having a corresponding cell size, including bright cells corresponding to a first binary value and dark cells corresponding to a second binary value different from the first binary value. The dark cells include a center portion being recessed relative to the surface thereby leaving a recess bounded by a peripheral wall in the corresponding dark cell, the recess having a depth of at least 100 microns and having an opening with a width ranging between 400 microns and 1750 microns and representing between 30 percent and 99 percent of the corresponding cell size such that the corresponding dark cell appears dark to an optical reader. The depth, the width and the cell size of the dark cells provide a shot blast resistance to the laser-marked identifier.