Steel Marking

Steel

Alphanumeric Marking

Alphanumeric marking forms the foundation of industrial traceability: serial numbers, batch numbers, part identifiers, internal references and variable data such as date, time or production counters. Serial numbers typically range from 6 to 12 characters, whilst internal references commonly fall between 4 and 10 characters.
As a general rule, character heights of 2 to 5 mm are used for comfortable human readability, with smaller sizes (0.3 to 1 mm) specified for automated vision reading systems.

• Laser marking on steel delivers fine resolution (typically down to ~0.05 mm) and excellent contrast on stainless steel and heat-treated steel, making it the preferred process for small characters and 2D codes.
• Dot peen marking on steel creates a permanent indented mark, frequently specified for parts intended for painting or subject to abrasion, whilst scribing on steel achieves depths in excess of 0.2 mm for outstanding long-term mark durability.

In practice, laser marking is the standard solution for Datamatrix code marking; it remains the reference technology for marking steel after painting and for compliance with DPM requirements on demanding part specifications.

• Scribing on steel is the preferred solution for VIN, structural beams and forged components.

When selecting a steel marking technology, key factors include surface condition (bright, brushed or painted), required mark depth, and integration with vision inspection systems and ERP platforms.

Steel

Datamatrix 2D Code

Datamatrix ECC200 codes, widely deployed across automotive, aerospace and pharmaceutical industries, enable a high density of information to be encoded within a very small footprint (2 to 10 mm).
When correctly configured, they remain machine-readable after painting or galvanising, with cell modules typically ≥0.25 mm to ensure reliable vision system verification.
On steel, performance is outstanding: thousands of parts can be marked with read rates consistently exceeding 99%. In production environments, these codes integrate directly with process control systems and tracking tools such as MES platforms, streamlining logistics management and maintenance operations.

• Fibre laser marking is the reference solution for Datamatrix marking on steel, delivering high contrast, high throughput speed and exceptional repeatability.
• Dot peen marking remains a robust alternative for demanding production environments, though it requires larger cell modules and yields lower contrast than laser.
• Scribing on steel is rarely suited to high-density codes. To ensure reliable reading, it is strongly recommended to validate each marking configuration against multiple readers and variable lighting conditions, and to verify compliance with applicable contrast criteria.

ACIER

QR Code

Moins utilisés que les Datamatrix, les QR codes restent appréciés lorsqu’une lecture smartphone/tablette est souhaitée. Leur grande capacité (jusqu’à plus de 4 000 caractères) permet d’encoder directement URL et informations détaillées.

• La gravure laser fibre est la solution privilégiée pour les QR codes sur acier : il offre une résolution fine, un contraste élevé et permet des modules compacts (en général ≥ 0,4–0,5 mm). Les sources fibre 20–50 W sont courantes, et les lasers MOPA sont utilisés lorsque le contrôle précis de l’impulsion est nécessaire, notamment sur l’inox.

Steel

1D Barcode

1D barcodes remain widely used for the linear identification of steel parts, particularly in logistics operations and spare parts management.
The most common formats — Code 128, Code 39 and EAN — are capable of encoding between ten and twenty characters. Laser marking on steel with a bar width of 0.15 to 0.25 mm consistently ensures reliable scanner readability.
They are well suited to assembly lines equipped with fixed short-range readers. Laser marking enables high-speed output (up to 1 to 2 codes per second), whilst dot peen marking, though slower, offers superior mark durability in abrasive or harsh operating environments.

• Laser marking is the preferred solution for barcodes on steel where bar edge definition is critical: it delivers high contrast, sharp line edges and outstanding repeatability throughout production.

Steel

Deep Marking on Steel

For applications where long-term durability is paramount, deep marking is the reference solution: marks remain legible after machining, painting, shot-blasting or galvanising.
In the automotive sector, deep marking is primarily used for VIN marking on chassis, where mark continuity and depth are critical for regulatory compliance and anti-fraud requirements.
In steel construction and offshore applications, structural beams and flanges are deep-marked to remain legible after shot-blasting and painting, whilst withstanding thermal cycling and corrosive environments.
The rail industry and machine tool sector also rely on deep marking for forged parts and safety-critical components, with minimum mark depths specified within contractual and normative requirements. These robust permanent marks guarantee long-term traceability and eliminate the risk of costly part replacement.

• Scribing on steel is the most effective method for achieving significant mark depths, typically between 0.2 and 0.5 mm depending on steel hardness.
• Dot peen marking on steel offers an excellent balance between robustness and throughput speed, with achievable depths of 0.05 to 0.6 mm at high production rates.
• Laser marking on steel can achieve deep marking through multipass processing, but is typically limited to approximately 0.01–0.2 mm, which increases cycle time accordingly. It becomes advantageous where fine character definition is required, but beyond 0.3 mm depth, scribing or high-force dot peen marking are more appropriate solutions.

In practice, the selection of the permanent steel marking technology is driven by operational constraints: scribing is preferred for forged components destined for shot-blasting, whilst dot peen marking is well suited to parts that will subsequently be painted.

Steel

Logo and Pictogram

• Laser marking on steel is the preferred solution for logos and fine detail: a 20–50 W fibre laser achieves line widths of 20–50 µm and produces legible logos from as small as 1.5 mm, making it ideal for identification plates and cast components.
• Where maximum resistance to post-marking treatments is required (shot-blasting, galvanising), a logo deep-marked by scribing offers greater long-term durability than a laser mark.

The choice is also determined by end-use requirements: pictograms that must remain visible after painting are frequently produced by dot peen marking, whilst compliance symbols require the precision and contrast that only laser marking can reliably deliver.

Automotive & Mobility

• Engine number marking (engine block, cylinder head, crankcase): laser marking or dot peen marking of serial numbers, alphanumeric codes and Datamatrix codes.
• Shock absorber reference marking (tubes, rods, steel bodies): laser marking of product references, barcodes and Datamatrix codes.
• Identification of connecting rods, shafts and gears: dot peen marking of forged steel parts — batch numbers, Datamatrix codes and manufacturer internal references.
• Chassis & engine subframe: deep scribing of the structural identification number for lasting legibility and full resistance to paint coating.

Aerospace

• Marking of critical steel parts (landing gear): dot peen marking with adapted stylus of serial numbers and Datamatrix codes with minimal mechanical stress, delivering a stable, permanent mark on high-strength steel.
• Structural fastener marking (fittings, hinges…): dot peen marking of Datamatrix codes on machined steel parts, and dot peen marking of structural references on forged steel components.
• Tooling marking (maintenance tools, jigs and fixtures): dot peen marking of certification logos and QR codes, producing a legible, non-distorting permanent mark.
• Forged component marking (brackets, pins, pivot joints): dot peen marking of batch references and traceability codes, ensuring high mechanical mark integrity in demanding service environments.

Rail

• Bogie component marking (frames, cross members, bolsters, axle boxes): scribing of serial numbers and maintenance codes for a deep permanent mark with lifetime legibility.
• Axle, pin and railway shaft marking: laser marking of Datamatrix codes on machined steel surfaces, and dot peen marking of identification numbers.
• Coupler and interconnection component marking: scribing of batch numbers and assembly references, ensuring full resistance to anti-corrosion treatments and delivering a continuous deep permanent mark.
• Painted steel part marking (side members, chassis elements): scribing of structural serial numbers and Datamatrix codes.

Energy, Oil & Gas

• Steel flange marking (ANSI, API, DIN): deep scribing of batch numbers and Datamatrix codes on rough surfaces, ensuring full resistance to saline and corrosive environments.
• Valve and industrial fitting marking: dot peen marking on unfinished surfaces of manufacturer references and serial numbers, maintaining legibility despite contamination, deposits and abrasion.
• High-pressure steel connector marking: scribing of serial numbers for a mark that remains legible after shot-blasting.
• Steel pipeline marking: portable dot peen marking directly on large-diameter steel tubes.