Mastering materials to go further

THERMILYON Group specializes in heat treatment and vacuum coatings for mechanical engineering.

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Improve the mechanical performance of your parts

A true pioneer in contract heat treatment for the subcontracting industries, the THERMILYON group has been capitalizing on technical innovation and service provision in heat treatment and vacuum deposition since 1960.

With a network of 9 sites in France and abroad, the THERMILYON Group favors close relationships with its partners and active listening to understand their needs and challenges.

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Solutions tailored to your needs

To ensure that our advice is always well-informed and objective, the THERMILYON Group offers a wide range of solutions to provide treatment adapted to the environment and constraints of the room.

Heat treatment
Heat treatment
parts partially coated with platin vacuum coating
Vacuum deposition
Vacuum deposition
1960

Year the THERMI-LYON Group was founded

5000

More than 5,000 customers in France and abroad

32

Millions of euros in sales

20

Millions of euros in human and technological investment over the past 4 years

165

employees

100

100% of our sites are certified

expertise in every market

To meet the expectations and requirements of certain markets, our sites are specialized and organized by market sector.

Our partners

fim logo
logo uimm auvergne rhone alpes
logo of A3TS, the association for heat treatment and surface treatment
logo cluster aeronautique auvergne rhone alpes
logo cluster aeronautique aerospace valley
woman looking through a microscope
loading a nitrex nitriding furnace at Thermi-Picardie

    Our locations near you

    Trempelec
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    Thermi-Loire
    • 143 Avenue Benoît Fourneyron 42160 ANDRéZIEUX-BOUTHéON
    • +33477555230
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    Thermi-Garonne
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    Thermi-Bugey
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    Infra-Therm
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    Thermi-Picardie
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    Thermi-Metalurgica
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    Thermi-Lyon
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    Thermi-Platin
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    Our certifications

    ISO 13485
    ISO 13485 certification logo

    ISO 13485 establishes the criteria for the quality management system of an organization providing medical devices and related services in compliance with customer requirements and applicable regulations.

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    ISO EN 9100

    EN 9100 certification guarantees the quality management system requirements of the ISO 9001 series, and specifies additional definitions and notes for the aerospace and defense industry.

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    IATF 16949
    logo IATF 16949 certification dedicated to the automotive industry

    The IATF 16949 standard, dedicated to the automotive sector, establishes criteria for quality management processes, encouraging continuous improvement, defect prevention and the reduction of non-conformities and scrap within the automotive supply chain.

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    NADCAP Heat Treating
    logo nadcap heat treating

    NADCAP is an accreditation program for aerospace and defense subcontractors, designed to ensure the quality and reliability of products and services. This accreditation focuses on the special processes employed in the manufacture, testing and maintenance of components and systems used in these industries. Within the THERMILYON Group, NADCAP applies only to the special heat treatment process.

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    ISO 9001

    The ISO 9001 standard, widely recognized throughout the world, helps organizations improve their performance by meeting quality management system requirements and demonstrating a commitment to customer satisfaction.

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    See all our certifications
    Customer testimonials

    Cédric Lancieux

    Technical Director, Euroteknika 

    "We needed to call on a company skilled in vacuum coating to ensure lasting quality for our products. It was thequality aspect that drew me back to them. We make products that stay in patients' mouths; quality is paramount in our business, and it's an aspect that Thermi-Platin more than lived up to. What Euroteknika needs is to differentiate itself in the market, and the coating produced by Thermi-Platin is a differentiator. Today, they are even proactive and solution-oriented. They come to us with real answers."

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    Portrait of Cédric Lancieux, Euroteknika employee

    Claude Madelmont

    Borg Warner Supplier Selection Manager

    "We specialize in what's known as the powertrain; that's everything to do with the engine and transmission. These parts have electromagnetic and wear-resistance characteristics. This is a very important point. The THERMILYON Group specializes in controlled atmosphere nitrocarburizing. This involves heat-treating the part to make it harder and more resistant to wear. This is a state-of-the-art treatment. Trempelec processes 15,000 to 25,000 partsat a time".

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    Portrait of Claude Madelmont, Borgwarner collaborator

    Damien Pignol

    Methods and Supply Chain Engineer at Lisi Aerospace Additive Manufacturing

    "When it comes to research and development aimed at creating new treatments to meet emerging challenges, Thermi-Garonne clearly stands out for its receptiveness and ability to propose innovative solutions, setting itself apart from the competition.
    Thermi-Garonne's uniqueness lies in its 100% management of LISI Aerospace Additive Manufacturing parts."
    As for the service offered by Thermi-Garonne, Damien Pignol expresses great satisfaction, ranking them among the top three suppliers for the company.

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    lisi aerospace logo

    Jérôme Lefebvre

    Purchasing manager at ERMO-tech

    "We specialize in the cosmetics, pharmaceuticals, medical and fine wall sectors, as well as in high-precision, high-speed closures. Thermi-Platin treats certain parts of our molds to extend their service life. All contact, friction and sliding between parts need to be hardened with DLC, a surface coating. Today, we have an average lead time of 3 days with Thermi-Platin. Thermi-Platin has been able to offer relevant products and prove its responsiveness to the needs of the ERMO group. They also provide us with a partner and technical support in our search for solutions.

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      Increase the performance of your parts

      The THERMILYON Group is your partner for improving your mechanical parts. Our teams will help you choose the treatment best suited to your needs.

      Contact us

      Our latest news

      Find out all the latest news about the THERMILYON Group as well as heat treatment and vacuum deposition.

      heat-treated stainless steel tanks
      Thermochemical treatments for austenitic stainless steels
      Stainless steels are metals renowned for their anti-corrosion properties. Since its creation, THERMI-LYON has been offering its customers a range of thermochemical treatment solutions for austenitic stainless steels on a subcontracting basis. Over 60 years' experience in the treatment of stainless steels [...]
      December 19, 2024
      Thermochemical treatments for austenitic stainless steels
      Steel bars of various sizes, illustrating annealing and tempering processes
      Annealing and tempering: what are the differences and what are the different types of annealing?
      Annealing and tempering are among the heat treatment techniques applied mainly to steels (copper alloys, aluminum and titanium too). Both methods involve heating parts to precise temperatures, which vary according to the process, but do not serve the same purpose. There are two main types of annealing [...].
      December 10, 2024
      Annealing and tempering: what are the differences and what are the different types of annealing?
      stepped quenching diagram
      A closer look at step quenching and its advantages
      Staged quenching is based on cooling in stages. It includes a traditional initial heating phase, to reach a given temperature, but requires controlled cooling to be divided into several stages. This process offers a number of advantages, including a reduced risk of breakage or deformation, compared to quenching with [...].
      November 18, 2024
      A closer look at step quenching and its advantages
      Bonded varnish Complementary treatment to heat treatment
      Why choose glide varnish as a complementary treatment?
      Bonded coatings are an excellent way of improving the coefficient of friction of metal parts. Applied, possibly following a heat treatment operation, it ensures that the parts slide better together and reduces the risk of seizing. This technology is used particularly in the construction and screw industries, but also in the [...]
      November 18, 2024
      Why choose glide varnish as a complementary treatment?
      plasma and ion cementation
      When to use plasma-assisted carburizing?
      Plasma-assisted low-pressure carburizing, also known as ion carburizing, is a heat treatment based on carbon diffusion. This method is used to reinforce the resistance of materials to wear, and above all, it uses vacuum technology. Developed in France by the Thermilyon group in the 1990s, this technology may not be [...]
      October 23, 2024
      When to use plasma-assisted carburizing?
      image of a decarburized metal part
      How to avoid decarburization?
      Decarburization is one of the everyday challenges associated with the heat treatment of metals. It is a chemical reaction that takes place when steel parts are heated in the presence of oxygen. The carbon present in the treated materials evaporates, causing them to lose their natural resistance to wear and tear, and to present a greater [...]
      October 17, 2024
      How to avoid decarburization?