Armco Inc.

William J Scumacher

James N Cordea

Harshad V Sheth

Mark J Gore

A nonmagnetic austenitic stainless steel and articles produced therefrom, such as drill collars, having a 0.2% yield strength of at least 690 N/mm.sup.2 (100 ksi), excellent resistance to intergranular stress corrosion, good ductility, good corrosion resistance, very low magnetic permeability (less than 1.004) and resistance to galling and wear which is typically at least 50% better than found in previous drill collars, the steel and articles consisting essentially of, in weight percent, from greater than 0.05% to about 0.10% carbon, greater than 18% to about 22% manganese, about 12.5% to about 17% chromium, about 1.5% to about 5% nickel, about 0.2% to about 0.4% nitrogen, about 0.2% to about 0.7% vanadium, about 1% maximum copper, about 1% maximum molybdenum, about 2% to about 4% silicon, about 0.05% maximum phosphorus, about 0.03% maximum sulfur and balance essentially iron.

Growing community of inventors

Monroe, OH, United States of America

William J Scumacher