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Do you have questions about heat treatment and vacuum deposition? We've got the answer.

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Why coat molds?

Vacuum deposition on plastic injection molds reduces abrasive and adhesive wear, and improves sliding on components with metal-to-metal contact. This solution boosts productivity, reduces downtime for tool changes and maintenance, and improves part quality.

Why coat forming tools?

Vacuum deposition on die tools reduces abrasive and adhesive wear and improves sliding. This solution boosts productivity, reduces downtime for tool changes and maintenance, and improves part quality.

Why coat cutting tools?

Vacuum deposition on cutting tools significantly increases tool life, saves on purchasing costs and boosts machining productivity, while hot-wear resistance eliminates the need for lubrication.

Which sites are certified for the automotive sector?

The TREMPELEC and THERMI-LOIRE sites have IATF 16949 automotive certification. However, other Group sites without automotive qualifications are able to respond to the market.

Which sites are certified for aeronautics?

THERMILYON Group sites certified for the aerospace market are THERMI-LYON, THERMI-LOIRE, THERMI-GARONNE and, more recently, THERMI-PICARDIE.

Which sites are certified for the medical sector?

The Thermi-Lyon group sites certified for the medical markets are THERMI-LYON and THERMI-PLATIN. The THERMI-BUGEY site is in the process of being certified.

Is it possible to harden an aluminum alloy?

Yes, some aluminum alloys can be quenched and tempered to improve their mechanical strength. This treatment is only available for alloys from the 2000, 6000 and 7000 steel mills. 

What is the advantage of a DLC vacuum depot?

A low-temperature carbon-based coating, it not only offers wear resistance, but also an excellent coefficient of friction. It is the anti-seize coating par excellence. It is biocompatible, making it widely used in the medical and food sectors.

What is the benefit of SNT treatment?

This treatment is applied to ferritic stainless steel. Improves resistance to wear and galling without compromising corrosion resistance. Surface hardening by diffusion.

What is the benefit of THERMI-SP treatment?

This treatment is applied to austenitic stainless steels. Improves resistance to wear and galling without compromising corrosion resistance. Surface hardening by diffusion.

What is the advantage of surface induction hardening?

The advantage is to heat parts locally in very precise zones, so as not to alternate zones that do not require hardening. This treatment is energy-efficient and easily automated for large production runs. This treatment is particularly well suited to large production runs.

Why nitriding/nitrocarburizing?

Diffusion of nitrogen on the surface of the part to considerably improve mechanical strength and wear resistance on the surface, while maintaining good core strength. This treatment greatly improves wear resistance, but as the temperature is low (500°C), it causes very little deformation and can be applied to a finished part.

What is the advantage of carburizing / carbonitriding?

Diffuse carbon (carbon and nitrogen in the case of carbonitriding) on the surface of the part, to considerably improve the part's mechanical strength and wear resistance on the surface, while maintaining good core strength.

What's the point of tempering?

The aim is to improve mechanical strength (hardness, yield strength, breaking strength, elongation) throughout the volume of the part. This enables parts to withstand a certain mechanical stress and extend their service life. 

What are the maximum sizes of parts that can be processed?

In vacuum processing, parts can have a diameter and height of 1800cm. 1500kg

In atmosphere treatment: 1500cm long, 1200cm wide and 900cm high. Maximum weight: 2000kg

Gas nitriding: 1500 diameter, 3500 high. 5000 kg

Ion nitriding: 1500 diameter, 3000 high. 3500 kg

What is the advantage of atmospheric treatment?

Atmospheric heat treatment enables the use of low-cost steels. Atmospheric technologies are ideal for large-scale production runs and large dimensions.

What is the advantage of vacuum processing?

The main advantages are the ability to obtain perfectly clean parts after treatment, and to significantly limit deformation when cooling under neutral gas. Vacuum technology furnaces are heated by electricity, not gas. What's more, the absence of atmosphere eliminates any risk of oxidation. These processes are the most environmentally-friendly of all heat treatments.

What machining allowances need to be taken into account for vacuum deposition operations?

Vacuum deposits are of the order of a few microns, and are applied to finished parts. As a result, every precaution must be taken to anticipate deformation. Dimensional tolerance must take into account the extra thickness created by the deposit itself (a few microns).

What machining allowances need to be taken into account for heat treatment operations?

Heat treatment reveals different levels of stress from previous stages (manufacturing). These stress relaxations can lead to deformations that must be anticipated at the time of machining. In the case of heat treatment in the mass (quenching, tempering), these extra thicknesses depend on the dimensions of the part, but are of the order of a few tenths to 1 mm.

To limit the level of deformation, it is advisable to carry out a stabilization treatment on the blank.

What do I need to know when consulting a customer or placing an order for vacuum deposits?

Nature of steel or carbide, if steel treated, please specify the treatments carried out. Desired characteristics (hardness), quantities of parts per shipment and per year, drawings of the part and specifications. If possible, how the part will be used and its final purpose.

What do I need to know when requesting or placing an order for heat treatment?

Type of steel, desired steel characteristics (hardness), quantity of parts per shipment and per year, part drawings and specifications. If possible, the operating mode of the part and its final use.

What are the elements of heat treatment? 

To carry out a heat treatment, we first need to take into account the part's use and the mechanical stresses it will have to withstand in its environment. Depending on these factors, the material/treatment pairing is defined.

Why is heat treatment used in industry?

Heat treatment is one of the only ways to improve the mechanical strength of metals, and therefore their performance. Alloys such as steel, stainless steel, aluminum, titanium and copper all have improved mechanical strength, wear resistance, seizure resistance and corrosion resistance thanks to heat treatment.

What are the main types of heat treatment?

There are two main types: softening treatments to improve the shaping or machining of parts, modify or improve the metallurgical structure or defragilize certain mechanisms. Hardening treatments in the mass or on the surface to improve the mechanical performance of components.

How is heat treatment carried out? 

Heat treatment is carried out using furnaces. There are air, atmosphere, vacuum, plasma and induction furnaces.

When should a heat treatment be carried out?

Heat treatment is required when the mechanical performance of the alloys in their natural state needs to be increased. Depending on the type of treatment, heat treatment can be carried out on raw, rough or finished machined parts.

Why heat treatment?

Either to improve mechanical performance such as tensile strength, impact strength, wear, seizure or to soften the metal to make it more malleable (machinability, shaping).

What is heat treatment?

It's an operation that modifies the internal structure of an alloy to change its properties. In general, there are 3 phases: heating, holding at temperature and slow or rapid cooling (in this case called quenching).

What types of parts are typically processed by low-pressure carburizing at Thermi Lyon?

Parts requiring a high degree of cleanliness (e.g. holes, bores, finished parts), highly machined parts sensitive to deformation, stainless steel parts, etc.

Why are vacuum furnaces used in low-pressure carburizing? 

Vacuum furnaces guarantee the absence of air, and therefore oxygen, in the furnace. So there is no oxidation. What's more, the low-pressure carburizing process operates at a very low pressure compared with atmospheric pressure, hence the use of vacuum pumps to reach this pressure level.

What advantages does low-pressure carburizing offer for industries such as the automotive industry?

Cleanliness and a lower level of deformation enable us to make financial savings by eliminating the need for subsequent washing or sandblasting operations, and by reducing the number of repeat machining operations.

How does low-pressure carburizing differ from traditional carburizing?

Low-pressure carburizing uses furnaces with electric heating, very small quantities of carburizing gas and often neutral gas cooling. Traditional carburizing uses furnaces with gas heating, an atmospheric pressure carburizing atmosphere and oil quenching.

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.

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 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...

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 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 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.

Do you have a question or a need?

Our team can advise you on the feasibility of your project and the processes best suited to your needs.

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