Abstract: An alloy and alloy product has about 1.3% to 1.7% by weight concentration of silicon, along with iron, alloying elements, and inevitable impurities and exhibits improved resistance to hydrogen embrittlement and sulfide stress cracking in an intensive hydrogen-charged medium wherein H from the medium acts as an alloying element. The alloy is characterized by an Fe--Si--H system wherein Fe is a donor element with respect to Si and Si is an acceptor element with respect to Fe. Further, the alloying elements are Fe--Si noninteractive elements with respect to Fe and Si, such that the presence of the alloying elements are not donor or acceptor elements with respect to Fe or Si. In several alloy compositions, the alloy has between about 1.38% to 1.63% weight Si. The alloy may further include between about 0.10% to 0.25% weight of C. In one particular alloy, the alloy composition includes about 0.18% of C; although, in one alloy product, an alloy is used having about 0.16% to 0.24% weight of C.