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duplex: ion nitriding + hard coating

Objective: Reinforce the mechanical strength of the underlay and improve wear resistance on the surface of the part.

Duplex is the superposition of two treatments:

- Thermochemical diffusion treatment (such as nitriding)

- A hard deposit

This type of double-treatment is particularly well suited to parts that are subject to high mechanical stress and require enhanced fatigue resistance in the undercoat and wear resistance on the surface.

injection mold with thermo-platin coating

Our process

Duplex processing requires perfect mastery of thermochemical treatment and vacuum deposition. These are two of the ThermiLyon Group's core competencies.

Recommendations

It is necessary to consult us in order to define :

The choice of steel

Choice of deposit

Treatment ranges

Machining routines

Ion nitriding

The part must first be thermochemically treated. Perfectly controlled ion nitriding enables significant depths to be obtained, depending on the steel (several 1/10th mm, for example), without creating a combination layer (detrimental to deposit adhesion).

Vacuum deposition

Ion nitriding is followed by vacuum deposition. Both treatments should preferably be carried out in the same chamber, without intermediate cooling, to ensure a high quality interface between nitriding and deposition. Modern vacuum deposition technologies enable in situ nitriding.

    Features and benefits

    Duplex treatment combines the advantages of nitriding and vacuum deposition.

    Processing of stressed parts

    Duplex treatment can be used for parts subject to high mechanical stress and those with complex geometries.

    economic

    Low-alloy steel can be used instead of high-alloy steel

    service life

    Increase part life by a factor of 2 to 10, depending on steel type and application.

    cleanliness

    Improved surface finish of manufactured parts.

    short deadlines

    Reduced machine downtime thanks to two treatments combined in a single cycle. By choosing the THERMILYON Group, you can combine two suppliers into one for short, controlled lead times.

    Maintenance

    Reduced tool maintenance (dismantling for polishing).

    For study and order

    Information to be communicated :

    - Steel grade (standardized designation preferred)

    - Previous treatments.

    - Functional parts, geometric tolerances to be respected

    - Hardness tolerances.

    - Thickness required

    - Part layout, weight, number of parts per shipment and per year.

    Ask for a quote

    business sectors concerned

    Duplex treatment is recommended for parts subject to high mechanical stress, such as: deep drawing dies, mold cavities, containers, form rollers, cams, gears....)

    Our various documentations

    Technical sheet Duplex treatments

    See all our documentation

    Our FAQs

    What is vacuum deposition?

    Vacuum deposition is a surface treatment used to deposit a material or alloy on a mechanical part.

    The use of vacuum technology ensures a perfectly clean, non-polluting process.

    It is not subject to REACH legislation.

    What are the advantages of PVD technology?

    This process greatly increases resistance to wear, abrasion, friction and corrosion. As a result, component life is greatly extended.

    Standard thicknesses are of the order of 3µm and deposition is carried out on finished parts.

    What's the difference between PVD and PACVD?

    PVD is physical vapor deposition. The element to be deposited is obtained by evaporation or sputtering via a physical process. PACVD is plasma-assisted chemical vapor deposition. The element to be deposited is obtained from chemical reactions. Plasma enables this chemical reaction to take place at lower temperatures.

    What are the industrial applications of vacuum deposition?

    Vacuum deposits are classified into several categories: anti-wear, friction, decorative and biocompatibility. The applications are therefore very varied: automotive components, aerospace, tooling, cutting tools, medical devices, decorative parts...

    How do I choose the right deposit method?

    The deposition method depends above all on the nature of the coating to be deposited and the substrate.

    If the substrate cannot be heated to high temperature, the deposition must be carried out using low-temperature technology.

    If the coating to be deposited consists of a solid element (metal or graphite target), a physical process such as PVD is used. If the coating consists of a gas or liquid, a chemical process such as CVD or PACVD is used.

    What is the purpose of case-hardening? 

    Incorporate carbon below the surface of the steel part to improve fatigue and wear resistance on the surface, while maintaining good core mechanical properties.

    See all FAQs

    Do you have a question or a need?

    Our design office can advise you on the feasibility of your project.

    Contact us

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