How It Works
Electrochemical etching starts by creating an image with a stencil. The image is then transferred to the metal surface with electrolyte and electric current. The process produces sharp, clean impressions without stress, damage or distortion.
The Electromarking Process
Clean Surface
Prepare the metal surface by cleaning it thoroughly with a neutralyte to remove oils, dirt, and oxidation.
Position Stencil
Place your custom or standard stencil firmly on the cleaned metal surface. Tape it down to keep it in place.
Apply Electrolyte
Apply the appropriate electrolyte solution to the pad used on the marker.
Apply Current
Press the marker to the stencil for 2-5 seconds using AC (DC is a little longer). The current creates the permanent mark or etch.
AC vs DC Marking
AC Marking
Alternating Current
What It Does
AC current creates a dark or contrasting mark with a shallow etch depth of 0.0001" to 0.0002". During the marking cycle, oxide is deposited on the surface, creating a corrosion-resistant, permanent mark.
Best For
- • Logos and branding
- • Text and serial numbers
- • High-contrast dark marks
- • Knife maker marks
- • Quick identification marking
Characteristics
- • Dark black surface mark
- • Faster marking process (2-3 seconds)
- • Minimal depth penetration
- • Excellent visibility
DC Etching
Direct Current
What It Does
DC current creates a deep etch ranging from 0.0001" to as deep as 0.010". Metal is completely removed during the marking cycle, leaving a clear or etched mark that is permanently etched into the metal surface.
Best For
- • Permanent serial numbers
- • Compliance and regulatory marking
- • Deep identification marks
- • Parts requiring maximum durability
- • Aerospace and automotive applications
Characteristics
- • Frosted, etched appearance
- • Deep marking (up to 0.010")
- • Longer marking time (4-6 seconds)
- • Maximum permanence
Safety & Best Practices
Safety First
- • Always wear appropriate PPE including gloves and eye protection
- • Ensure proper ventilation when working with electrolytes
- • Keep electrolytes away from skin and eyes
- • Follow manufacturer guidelines for electrical safety
- • Store electrolytes in proper containers away from children
Best Practices
- • Clean the surface thoroughly with neutralyte before marking for best results
- • Use the correct electrolyte for your metal type
- • Apply consistent pressure during marking
- • Test on scrap material before marking final parts
- • Clean and neutralize the marked area after processing
Common Mistakes to Avoid
- • Using too much or too little electrolyte
- • Insufficient surface cleaning
- • Applying uneven pressure
- • Using the wrong electrolyte for the metal type
- • Not allowing proper contact time
Frequently Asked Questions
Electrochemical marks are permanent for the life of the part under normal use. Because the process removes or oxidizes metal at the surface rather than laying ink or coating on top, the mark becomes part of the metal itself. It will not wear off through handling, washing, solvents, or light abrasion, and it will not fade with UV exposure the way printed or painted marks do.
In practice, marks on knife blades, surgical instruments, aerospace brackets, and automotive components routinely last decades. IMG has customers still running marking units purchased in the 1960s, producing marks today that are indistinguishable from the ones made fifty years ago.
The only way to remove an electrochemical mark is to physically grind or machine away the top layer of metal. That permanence is exactly why electrochemical marking is specified for traceability, compliance marking (including MIL-STD-130 IUID), and maker's marks where authenticity matters.
Electrochemical marking works on any metal that conducts electricity, which covers the vast majority of industrial and consumer alloys. Commonly marked metals include stainless steel (all grades), carbon steel, tool steel, titanium, aluminum, brass, copper, nickel, Inconel, and Hastelloy. It also works on plated surfaces like chrome and nickel plating.
The process does not work on non-conductive materials such as plastics, ceramics, anodized aluminum (the anodized layer is an insulator), or painted surfaces. For those, a different marking method is required.
Different metals require different electrolytes to produce a clean, high-contrast mark. Stainless steel uses one formulation, aluminum another, titanium another. IMG supplies electrolytes matched to each metal family, and our team can recommend the right combination for your specific alloy. If you are marking a metal you have not tried before, send us a sample and we will test it for you before you commit.
Yes. IMG manufactures dual-output marking units that deliver both AC and DC from a single machine, letting you switch between the two with a control on the front of the unit. This is the most versatile setup for shops that mark a variety of parts or need both visual contrast and etch depth.
AC marking produces a dark, high-contrast surface mark that is ideal for logos, part numbers, and legibility on stainless and tool steel. DC marking produces a deeper etch with less surface darkening, which is preferred for traceability marks that must survive surface finishing, or for aerospace and medical applications where etch depth is specified.
If you only ever need one mode, a dedicated AC or DC unit is less expensive. But most customers who buy a single-mode unit eventually wish they had both. For that reason, dual AC/DC units are our most popular product line. Our team can help you decide which unit size and configuration fits your volume and part mix.
For most applications, the cost per mark is under one cent. A single bottle of electrolyte and one stencil can produce thousands of marks, and the electricity draw of a marking unit is negligible. Once the equipment is paid for, the only recurring costs are electrolyte, felt pads, and stencils.
A realistic breakdown for a typical shop marking a logo or part number on stainless steel: electrolyte and felt pad wear are fractions of a cent per mark, stencils are pennies per mark for custom and near zero for reusable, and labor is three to ten seconds per part.
Compared to laser marking (tens of thousands in equipment cost), dot peen (slower and noisier), or outsourced engraving (dollars per part plus shipping), electrochemical marking has the lowest total cost per mark of any permanent marking method for small to medium production runs. For high-volume production, the cost advantage only grows.
We are happy to run the numbers for your specific part and volume. Send us a drawing and a target quantity and we will give you a cost per mark estimate before you buy anything.
No formal training is required. Electrochemical marking is one of the simplest permanent marking methods to learn, and most operators are producing clean, consistent marks within their first hour of use. If you can operate a stapler, you can operate a hand marker.
Every IMG unit ships with a quick-start guide, a recommended settings chart for common metals, and access to our support team by phone or email. For bench marking setups and higher-volume production configurations, we include setup documentation and are available to walk your team through installation remotely.
The skills that separate a good operator from a great one come with practice: choosing the right electrolyte for the metal, dialing in the AC or DC setting for the desired contrast and depth, and maintaining the felt pad for consistent marks across long runs. These are easy to learn and hard to get wrong in a way that damages parts.
If you want hands-on guidance, our team in Utica is available by phone at 1-800-775-3824. We will walk you through your first marks in real time.
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