Abstract: A low carbon plus nitrogen, free-machining, austenitic stainless steel having improved machinability and excellent corrosion resistance. The steel composition in weight percent is carbon plus nitrogen up to about 0.06, chromium 16 to 20, nickel 6 to 14, manganese up to 0.60, sulfur 0.15 to 0.50, silicon up to about 1, phosphorus up to about 0.20, molybdenum up to about 1 and balance iron.

Abstract: A chromium-nickel-copper, age-hardenable martensitic stainless steel having improved machinability in the solution-treated and also in the age-hardened condition. The steel has carbon plus nitrogen up to 0.08%, preferably 0.05 or 0.035% for purposes of improved machinability.

Abstract: A powder-metallurgy method for producing tubular product having at least one surface and preferably an internal surface thereof clad with an alloy different from and preferably more resistant to destructive media than the material from which the remainder of the tubing is constructed. An assembly is constructed of a metal tubing having an internal surface to be clad and a tubular insert mounted generally axially within the tubing in spaced-apart relation to the internal surface thereof, which provides a generally annular cavity between the internal surface of the tubing and the tubular insert. This cavity is filled with metal particles of a composition to be clad on the tubing internal surface. The cavity is sealed and the assembly is heated to an elevated temperature at which it is forged to compact the metal particles introduced to the cavity to substantially full density and metallurgically bond the particles to the internal surface of the tubing to provide a desired destructive-media resistant cladding.