Advanced metallic alloys for the fossil fuel industries

Abstract

The fossil fuel industries are currently in crisis, for some rather strange reasons. The introduction of new technologies for extracting oil and gas has resulted in a decrease in market share for some of the middle eastern countries. They have therefore flooded the market with cheap oil in order to force the more expensive producers out of business. This has had consequences on investment in research and development because the focus shifts to survival rather than to the extreme engineering required to exploit more difficult deposits. Nevertheless, this crisis is necessarily a temporary affair and the need for better materials will not diminish in the long term.This special issue contains a number of papers on steels used in the manufacture of a variety of pipes. The American Petroleum Institute classifies linepipe steels as Grade A, B and X, 1 where the last grade has the most stringent requirements specified, with particular attention to toughness. The letter 'X' refers to chemical compositions containing chromium, copper, molybdenum, nickel, silicon, niobium, titanium, vanadium and zirconium either singly or in combination along with nitrogen and/or phosphorus if desired. It also represents a 10-20 ksi spread between the minimum yield and tensile strengths. The two digits after 'X' specify the minimum yield strength requirement of the steel in ksi 2 ; X80 therefore has a minimum yield strength of 80 ksi (555 MPa). In practice, the ultimate tensile strength of X80 is usually in the range 700-750 MPa 3 and will be dependent on the test orientation. 4