Staff metallurgist, Inland Steel Co., East Chicago, Ind.
Pages: 8 Published: Jan 1981
The properties required from free machining steels are machinability and surface finish; detrimental effects are the products of deoxidation. This paper describes the difficulties involved in producing high-carbon or continuously cast free machining steels, and the reasons for the virtual absence of free machining irons. Sulfur and lead as machinability promoters of steels, and the importance of the manganese/sulfur ratio, are considered, along with the forms available, manner of usage, recoveries, and recoveries from remelting scrap. The following topics are also discussed: ASTM specifications; phosphorus and nitrogen as chiefly surface finish promoters; manner of manufacture of ferrophosphorus and its properties and trends as affecting the steelmaker; products available, manner of usage, and recoveries from remelting scrap; nitrided alloys and their ASTM standards, manner of usage, recoveries, and recoveries from remelting scrap; selenium and tellurium as machinability enhancers; and possible future trends in the development of alloys for free machining steels.
free machining steels, ferroalloys, steel deoxidation, sulfur in steel, lead in steel, nitrogen in steel, phosphorus in steel, selenium in steel, tellurium in steel
Paper ID: STP27693S