Effects of chromium and tungsten on sulfide stress cracking in high strength low alloy 125 ksi grade casing steel

•Reducing the Cr content and adding W produced enhanced SSC resistance.•The coarse and semi-continuous M7C3 carbides were eliminated in the 0.5Cr steel.•W increased the tempering resistance and suppressed the coarsening of carbides.•The addition of W decreased the permeability and effective diffusivity of hydrogen.