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Industrial metal parts

Heat Treatment

Air Liquide draws on its extensive knowledge and technical expertise in heat treatment to provide customers with competitive gas solutions that are safe, reliable and fine-tuned to their needs. Our staff is on hand to support and optimise customers’ processes and control their costs.

Heat Treatment at a Glance

Metals, primarily steels, make up our trains, automobiles, machines… even our table cutlery. Before being used, they must be transformed through cutting, welding, or forming: a critical step in this transformation is heat treatment.

Heat treatment is a sequence of heating operations applied to metals - sheets, tubes, wires or parts - to improve their mechanical properties, by modifying their structure or composition. An inert gas, usually nitrogen, is combined with active gases like hydrogen, cracked methanol, natural gas or propane to create the heat treatment atmosphere inside the furnace.

It is most frequently applied to make metals - such as carbon steel, stainless steel, copper, aluminium, and titanium alloys - harder, more ductile, or more resistant. Heat treatment requires the use of dedicated gas combinations.


“With ALNAT™ we are able to improve our customers’ heat treatment processes, optimizing parameters and reducing deviations in the atmosphere.”

Laurent Coudurier, International Senior Expert

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What is the ALNAT™ offer?

ALNAT™ is Air Liquide’s dedicated offer for heat treatment applications. It includes the delivery of gases and gas-handling equipment, as well as different services for customers related to the generation, use and control of atmospheres in industrial heat-processing furnaces.

Heat treatment of metals requires a lot of expertise. There are many different processes where the gaseous atmosphere inside the production equipment plays a key role in final product specifications. Our customers know they can exchange with our experts on issues such as quality control, performance improvement, equipment reliability and safety. Part of our offer is a process audit of the customer´s heat-treatment furnaces that allows us to then offer customized solutions for troubleshooting, quality management, cost reduction or qualification of new products.

How does ALNAT™ improve customer performance?

In short, we lower the operating costs through optimizing processes. With ALNAT™ we are able to improve our customers’ heat treatment processes, optimizing parameters and reducing deviations in the atmosphere. This in turn improves the quality control for production and reduces costs (because non-quality has a high cost). Furthermore, we make their gas usage more efficient, and make recommendations to our customers about preventive maintenance. This helps them reduce possible disturbances while improving productivity throughput.

How does Air Liquide prepare customers for the challenges of tomorrow?

There are many challenges on the horizon, such as the development of new advanced materials, not least of which are titanium alloys in aeronautics, or ultra-high strength steels in automotive. Light-weighting is very important, particularly in transportation, to reduce fuel consumption and emissions. These will impact on heat treatment processes. Meeting increased quality requirements is another challenge, as is compliance with different Quality Management standards like NADCAP in the aerospace industry or CQI-9 for carmakers. For all these challenges, we work closely with our customers to develop new technologies and solutions.


Our Gas Solutions

At Air Liquide, our comprehensive offer is backed by a network of worldwide specialists to help execute challenging heat treatment projects. When it comes to heat treatment, we guarantee our customers a controlled atmosphere in terms of safety, efficiency, and reliability. Our offer covers a wide range of solutions, including annealing, brazing, carburising, cryogenic treatments and more.

Our primary offer for these heat treatment solutions is ALNAT™, a packaged offer that includes gas delivery, appropriate gas handling equipment, and further value-added services.

We provide customers with process and safety audits to optimise the usage of heat treatment furnaces and assist in trouble-shooting. Additionally, we train heat treatment personnel to ensure smooth and efficient processes.