Patent ID: 8328958

Claim:
A steel composition, comprising: carbon (C) between about 0.15 and 0.40 wt. %; manganese (Mn) between about 0.1 and 1 wt. %; chromium (Cr) between about 0.4 and 1.5 wt. %; molybdenum (Mo) between about 0.1 and 1.5 wt. %; wherein the average packet size, d packet of the steel composition, the precipitate size of the steel composition, and the shape factor of the precipitates are selected to improve the sulfur stress corrosion resistance of the composition; wherein the average packet size, d packet of the steel composition is less than about 3μm; wherein the composition possesses precipitates having a particle diameter, d p , greater than about 70 nm and which possess an average shape factor of greater than or equal to about 0.62; and wherein the shape factor is calculated according to 4Aπ/P 2 , where A is area of the particle projection and P is the perimeter of the particle projection.