Abstract: The alloys of the present invention provide austenitic, paramagnetic materials with high strength, ductility, and yield strength and good corrosion resistance in media with high chloride concentrations. Alloys of the present invention were developed because of the need by oilfield industries for superior materials. The alloys of the present invention may be used in drilling string components, and the tests performed demonstrate that such alloys exhibit properties balanced for very high yield strength, magnetic permeability, and corrosion resistance superior in every respect to presently available paramagnetic, high strength, corrosion resistant austenitic stainless steels.

Abstract: The alloys of the present invention provide austenitic, paramagnetic materials with high strength, ductility, and yield strength and good corrosion resistance in media with high chloride concentrations. Alloys of the present invention were developed because of the need by oilfield industries for superior materials. The alloys of the present invention may be used in drilling string components, and the tests performed demonstrate that such alloys exhibit properties balanced for very high yield strength, magnetic permeability, and corrosion resistance superior in every respect to presently available paramagnetic, high strength, corrosion resistant austenitic stainless steels.

Abstract: The present invention relates to a fully austenitic, nonmagnetic stainless steel which maintains the carbon concentration of the final steel near the solubility limit for carbon in the steel and adds columbium in an amount sufficient to stabilize the steel by columbium's preferential scavenging of carbon over chromium. This preferential scavenging substantially eliminates chromium carbide formation at grain boundaries in the solid solution of the final stainless steel product. A highly preferred stainless steel consists essentially of, by weight:16-20% Manganese,12-15% Chromium,5.0% Molybdenum max.,2.5% Nickel max.,1.0% Copper max.,0.75% Silicon max.,0.2-0.5% Nitrogen,0.04% Phosphorus max.,0.01% Sulfur max.,0.035% Carbon max.,Columbium at a concentration of at least ten times the Carbon concentration, andthe remainder being essentially Iron with incidental impurities.

Abstract: The present invention relates to a fully austenitic, nonmagnetic stainless steel which maintains the carbon concentration of the final steel near the solubility limit for carbon in the steel and adds columbium in an amount sufficient to stabilize the steel by columbium's preferential scavenging of carbon over chromium. This preferential scavenging substantially eliminates chromium carbide formation at grain boundaries in the solid solution of the final stainless steel product. A highly preferred stainless steel consists essentially of, by weight:16-20% Manganese,12-15% Chromium,5.0% Molybdenum max.,2.5% Nickel max.,1.0% Copper max.,0.75% Silicon max.,0.2-0.5% Nitrogen,0.04% Phosphorus max.,0.01% Sulfur max.,0.035% Carbon max.,Columbium at a concentration of at least ten times the Carbon concentration, andthe remainder being essentially Iron with incidental impurities.