Materials used in the design of hydrogen containment structures

6 Materials used in the design of hydrogen containment structures 

Low-alloy and carbon steels represent the bulk of structural metals, and we refer to them collectively here as ferritic steels to distinguish them from the 

Although low values of CE are specified to prevent martensite formation in welds [31], these regions are often still harder than the surrounding pipeline base metal. As documented in Section 3.4.1, higher hardness (i.e. higher yield strength) makes steel welds more susceptible to hydrogen embrittlement. 

Strain hardening is an effective method of strengthening austenitic stainless 

Alloy composition appears to be the primary distinguishing feature for hydrogen embrittlement resistance among the austenitic stainless steels. In particular, hydrogen embrittlement resistance increases with nickel content and several studies have demonstrated critical nickel content in the range of 10-12 wt% nickel [11,12,60], below which the embrittlement susceptibility increases dramatically, as demonstrated by the tensile ductility data in Fig. 

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