Method of making corrosion resistant austenitic steel
AssigneeAllegheny Ludlum Industries, Inc.
InventorAlbert G. Hartline, III
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Abstract
A substantially non-porous, austenitic stainless steel that is resistant to chloride pitting and a method of making it are disclosed. The steel includes from 21-45% manganese, from 10-30% chromium, from 1-4% nickel, from 0.85-3% nitrogen, up to 2% silicon, up to 1% carbon and the balance iron and residuals. In addition to containing elements within the above-noted composition ranges, the alloys must be such that: 1. % Cr + 0.8(%Mn) - 11.8(%N - 0.1) - 1.23(%Ni) .gtoreq. 28.5 ##EQU1## The steels are cast and worked to avoid a dwell period in the temperature range 1000.degree.-1600.degree.F.
Claims1
A method for producing a substantially nonporous austenitic stainless steel which comprises compositing an alloy consisting essentially of about 21-45% manganese, about 10-30% chromium, about 1-4% nickel, about 0.85-3% nitrogen, up to 1% carbon, up to 2% silicon, and the balance iron and residuals, wherein the composition is such that:
- 1. %Cr + 0.8(%Mn) - 11.8(%N - 0.1) - 1.23(%Ni) = 28.5 ##EQU3## melting said materials to form a homogeneous liquid phase and solidifying the resultant liquid phase by air cooling or quenching in the temperature range from about 1000.degree.-1600.degree.F.
Dependencies are inferred from the claim text.