As the UK and Ireland accelerate toward a hydrogen economy to meet net-zero targets, the safe containment of this unique element is paramount. Hydrogen presents significant metallurgical challenges that, if ignored, lead to catastrophic system failure. At NVFCL, we provide FITOK fluid system components engineered specifically to withstand these harsh conditions.

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The Dual Challenge of Hydrogen Containment

Hydrogen handling requires managing the element in both liquid and gaseous states, each affecting metal integrity differently:

• Low-Temperature Embrittlement: Liquid hydrogen must be stored at -252.9°C. At these cryogenic temperatures, many metals lose ductility and become brittle, making them prone to cracking.
• Hydrogen Embrittlement: In its gaseous state at ambient temperatures, diatomic hydrogen molecules (H2​) can dissociate into atomic hydrogen (H). These tiny atoms diffuse into the metal lattice, accumulating at grain boundaries and stress points, drastically reducing the material’s fatigue resistance.

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Material Selection for Hydrogen Infrastructure

Building lasting hydrogen systems requires a strict “materials matter” approach. Not all stainless steels are created equal when facing hydrogen.

 Austenitic Stainless Steel is the Gold Standard

Austenitic stainless steels, such as those used in FITOK’s 6-Series and 20-Series components, feature a face-centered cubic (FCC) crystal structure. This structure provides naturally high ductility and moderate strength, making it the premier choice for resisting both low-temperature and hydrogen-induced embrittlement.

 Ferritic and Duplex Steels Present Higher Risk

Ferritic, low-alloy, and duplex stainless steels are significantly more susceptible to cracking. Using high-strength materials that lack the proper austenitic stability can lead to rapid fatigue failure, especially under cyclic loading conditions.

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The Critical Role of Fatigue Resistance

While many focus on ductility (the ability to stretch before breaking), fatigue resistance is the real-world priority. Hydrogen handling systems are subject to constant vibration and pressure cycling.

Hydrogen atoms accelerate the accumulation of localized plastic damage. If the wrong grade of steel is used, these repeated stresses lead to:

• Safety Hazards: Uncontrolled leaks in high-pressure environments.
• Financial Loss: Increased downtime and frequent component replacement.
• Environmental Impact: Escaping hydrogen undermines the sustainability goals of the project.

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Why NVFCL and FITOK?

As the exclusive authorised distributor, NVFCL ensures that your hydrogen projects are built with FITOK’s specially formulated, high-nickel stainless steels. These materials are specifically designed to minimise the risks of hydrogen diffusion and maintain structural integrity across extreme temperature gradients.