Can hydrogen pass through the coating of a composite panel to reach the base layer?
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The medium contains hydrogen, so hydrogen-induced cracking must be considered for the raw materials. So, with this type of composite panel whose cladding is S30408, is it still necessary to conduct hydrogen-induced cracking tests on the base layer?
It is necessary to consider conducting hydrogen-induced cracking tests at the grassroots level.
Last time, one character was missing; it wasn’t necessary to consider conducting hydrogen-induced cracking tests at the grassroots level.
Thank you. Hydrogen won’t pass through the coating to reach the base layer, right?
It mainly depends on the operating conditions, such as the hydrogen partial pressure and operating temperature. Theoretically, stainless steel linings are used for corrosion protection, but they are not very effective against hydrogen; hydrogen can pass through the stainless steel and reach the underlying layer. In other cases, hydrogen-induced cracks form at the joint surfaces, which is what is commonly referred to as delamination.
1 Hydrogen will pass through the coating. 2 There is a risk of hydrogen stripping; generally, the thickness for cladding is 6.5 mm, while that for composite materials is usually 3 mm. 3 The hydrogen-induced cracking experiment is conducted in a wet hydrogen sulfide environment, so that experiment should not be carried out. But the hydrogen stripping experiment should be done.
One more question: why is it said that hydrogen can pass through the coating? Will hydrogen pass through the base layer?
Where else can I find relevant information?
You can consult the Nelson curve, which shows the hydrogen resistance conditions and effects for various metals (steels).
The Nelson curve doesn’t involve hydrogen passing through stainless steel, right? The guy just now said that hydrogen can pass through stainless steel layers; I’m quite interested and would like to find out where that claim comes from.
S30408 austenitic stainless steel can be used as a hydrogen-resistant steel for high temperatures