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Innovative Technology of Coating & Overlay for Maintenance and Repair

We would like to introduce a Japan’s Best Coating & Overlay Device already approved and installed by all of Japanese Automobile companies and NASA.



The SparkDepo is a new surface enhancement process, and deposits an alloy or applies a hard coating by means of electric sparks from rotating electrode.
Preventive maintenance of various machine components, tooling, dies, and molds can be accomplished by the application of hard coatings using WC, TiC, TiB2, Cr3C2, VC, etc. electrodes. Low heat input alloy overlay is posssible using the electrod of Ni, Co, Cu, or Al alloys. The SparkDepo process is truly a new plant maintenance technique. The use of SparkDepo really increases productivity and reduces maintenance cost because of the reduced maintenance time and parts inventory.

Advantages of SparkDepo Process

1. Easy to operate.
2. Portable and usable with 100 to 220 volt outlet.
3. On-site repair work which requires no dismantling of large machines.
4. Extremely low heat input eliminates distortion, pits, shrinkage, and internal stress.
5. Requires no pre and post heat treatment.
6. Provides excellent bonding by the formation of diffusion layer.
7. Rotating consumable electrode gives high deposition efficiency and produces excellent coating.
8. High power output allows thick coating and retains its property for extended period.
9. Very smooth as-coated surface is obtained with a vibratory applicator.
10. Inert shield gas (Ar, He, etc.) produces excellent thick coating.
11. Repeatable coating thickness and surface roughness can be obtained by adjusting the level of power output and frequency.
12. Finishing stock of the overlay can be kept to the minimum, reducing finishing time.
13. Repeated overlay is possible over worn out coating.
14. Environmentally safe. Produces no toxic gas, liquid, or unpleasant odor and noise.
15. Application of “DiaCoat”, fine spherical diamond particles, over the coating reduces the coefficient of friction.


The MicroDepo is a new coating and overlay system that takes advantage of the basic principles of electrical discharge machining (EDM), and applies hard carbide coatings and metal and alloy overlays.

The use of MicroDepo minimizes downtime for repair as well as parts inventory.
Resulting in lower cost yet in higher productivity.

Easy operation, Portable, Partial repair, Low heat input, High bond strength, On-site repair, In-line work, Economical.

1. Coating for Preventive Maintenance
Longer service life by applying a thin layer of WC?TiC?Cr3C2,VC, etc. that resists wear, heat and corrosion.

2. Overlay for Repair
Repairs wear, scuffing, corrosion, pinholes, cracks as well as corrects machining error with metal and alloy overlay.

Comparison with Other Low Heat Input Overlays*

1 Rapid deposition rate.
2 Easy deposition in corners and sharp edge restoration.
3 Strong bonding and no de-bonding in service.
4 Transfer of depositing material from a rotating electrode.
5 Deposition in holes and difficult to access areas.
6 Applicable aluminum and/or copper base alloys and electroforming molds.
7 Oxide free deposit using Argon shield gas.
8 Carbide coating.
(* Spot welding processes using powder, plate, wire, or paste.)

Comparison with TIG Welding

1 Low heat input with no melting of the base metal.
2 No distortion and residual stress.
3 No change in the hardness of the base metal.
4 Controlled thickness within 0.01mm.
5 Reduction in finishing time due to reduced finishing stock.
6 No requirement for pre/post heat treatment.
7 Carbide coating


Contact us for further information!

Mr. Tomáš Junek
Service Engineer
Phone: +420 233 320 090