Which process
for which material.

Stainless steel

303, 304, 316/316L, 17-4 PH, 15-5 PH, 410, 420, 440C

Primary

Anneal

Contrast

High

Data Matrix

Excellent

Black oxide anneal with no measurable surface removal; etched marks read gray to white.

• Annealing keeps the surface intact, which is why it is the default for medical instruments and implants.
• Anneal marks survive passivation (ASTM A967 / AMS 2700) when the oxide layer is fully formed. We verify post-passivation on request.
• MOPA pulse control enables stable color marking (blue, gold, bronze) for branding or color-coded parts.

Typical: Surgical instruments, implants, fasteners, valve bodies, food-grade components

Titanium

CP Grades 1–4, Ti-6Al-4V (Grade 5), Ti-6Al-4V ELI (Grade 23)

Primary

Anneal

Contrast

High

Data Matrix

Excellent

Dark gray to black anneal; strong interference colors are easy to produce.

• Titanium oxidizes readily, so annealed marks are dark and high-contrast at modest energy.
• Avoid deep engraving on fatigue-critical or flight hardware unless the drawing permits it; annealing is non-intrusive.
• Color marking is common for orthopedic instrument sets and size coding.

Typical: Orthopedic implants and instruments, aerospace brackets, fasteners, UID plates

Aluminum, bare

6061-T6, 7075-T6, 2024, 5052, cast A356 / 380

Primary

Etch

Contrast

Low–Medium

Data Matrix

Good

Light gray to white frosted etch; dark marks are achievable with tuned MOPA parameters but are lower contrast than on steel.

• Bare aluminum does not form a dark oxide the way steel does. For maximum contrast, anodize first and ablate.
• Deep engraving works well; fill with paint or epoxy when a permanent dark mark is required on bare stock.
• Cast alloys show porosity in the mark; expect grade variation on rough castings.

Typical: Machined housings, fixtures, tooling, brackets, heat sinks

Aluminum, anodized

Type II and Type III (hardcoat) anodize on any wrought alloy

Primary

Ablate

Contrast

High

Data Matrix

Excellent

Bright white or silver mark where the dye layer is removed, on a colored or black background.

• Black or dark anodize gives the highest-contrast Data Matrix of any common substrate.
• Ablation removes the dye, not the anodic layer; corrosion resistance is largely preserved on Type II. Hardcoat may show a slight step.
• Clear anodize marks poorly; specify a colored anodize when marking is planned.

Typical: Nameplates, control panels, enclosures, optical and electronic housings

Carbon and alloy steel

1018, 1045, 4140, 4340, 8620, spring steels

Primary

Etch

Contrast

High

Data Matrix

Good

Dark gray to black etch or anneal; deep engraving reads as a sharp recessed line.

• Marks readily. Engraved regions lose any plating or black oxide and may rust; specify post-mark coating if the part is not otherwise protected.
• Heat-treated surfaces mark fine; check hardness requirements before deep engraving on case-hardened parts.

Typical: Shafts, gears, weldments, tooling, fixtures, structural hardware

Tool steel

A2, D2, S7, H13, O1, M2

Primary

Engrave

Contrast

High

Data Matrix

Good

Crisp engraving for cavity and die identification; surface etch for tool numbers and heat lot.

• Deep engraving is typically preferred so identification survives regrinding and polishing.
• Multi-pass engraving handles stepped depths for cavity numbering and date wheels.

Typical: Molds, dies, punches, cutting tools, gauges

Brass, bronze, copper

C360, C260, C544, C110 copper, beryllium copper

Primary

Engrave

Contrast

Medium

Data Matrix

Fair

Reflective substrates; marks read as a matte recess or a darker oxidized etch depending on parameters.

• High reflectivity and conductivity at 1064 nm mean higher energy and slower speeds than steel.
• Pure copper is the hardest of the group; brass and bronze mark reliably.
• Paint fill after engraving is common for legible nameplates.

Typical: Electrical hardware, plumbing and valve components, plaques, bushings

Engineering plastics

PEEK, ABS, PC, PA (nylon), POM (Delrin), PP, PE, PVC, laser-additive grades

Primary

Foam / carbonize

Contrast

Variable

Data Matrix

Depends on grade

Dark carbonized mark on light resins or a light foamed mark on dark resins. Highly grade-dependent.

• PEEK, ABS, and PC mark well with a fiber laser. Natural POM, PP, and PE respond poorly without a laser-marking additive.
• Glass-filled grades mark more consistently than unfilled.
• Send a sample coupon before releasing a marked-plastic drawing; results vary by colorant and filler.

Typical: Medical device housings, connectors, fluid handling, consumer-durable parts

Coated and painted parts

Powder coat, e-coat, wet paint, black oxide, PVD, chem-film

Primary

Ablate

Contrast

High

Data Matrix

Excellent

Coating removed to expose the substrate; contrast set by the coating color versus the base metal.

• Ablation is selective; the substrate is generally untouched. On steel, the exposed window may need a clear coat.
• Thick powder coat produces a visible step; thin e-coat and PVD give the cleanest edge.

Typical: Enclosures, panels, brackets, consumer hardware, rating labels

Ceramics and glass

Alumina (Al₂O₃), zirconia, silicon nitride, borosilicate

Primary

Etch

Contrast

Medium

Data Matrix

Fair

Dark gray mark on alumina and zirconia; frosted surface mark on glass.

• Technical ceramics mark well with a fiber laser. Glass is marginal at 1064 nm and is quoted case by case.
• Micro-cracking risk on thin sections; test on a sample.

Typical: Insulators, substrates, wear components, lab hardware

Laser-markable labels and tag stock

Tesa 6930 / 6973 polyacrylic, anodized aluminum tag stock, stainless nameplates

Primary

Ablate

Contrast

High

Data Matrix

Excellent

White-on-black (polyacrylic) or black-on-silver (stainless) with a clean edge.

• Tamper-evident polyacrylic fractures on removal and is UV-stable outdoors.
• The right choice when the part itself cannot be marked: composites, painted assemblies, purchased equipment.

Typical: Asset tags, equipment nameplates, calibration labels, facility infrastructure