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A D V A N C E D M A T E R I A L S & P R O C E S S E S | J A N U A R Y 2 0 1 6 3 6 METALLURGY LANE Metallurgy Lane, authored by ASM life member Charles R. Simcoe, is a continuing series dedicated to the early history of the U.S. metals and materials industries along with key milestones and developments. PIONEERS IN METALS RESEARCH—PART IV EDGAR BAIN PIONEERED THE STUDY OF THE REACTION OF AUSTENITE TO LOWER TEMPERATURE PHASES DURING ISOTHERMAL TRANSFORMATION, RESULTING IN A NEW PHASE NAMED IN HIS HONOR — BAINITE. A fter finishing high school in Mar- ion, Ohio, Edgar C. Bain enrolled at The Ohio State University in Columbia University taught by William Campbell and Henry Marion Howe. He taught at Wisconsin for one hardening they proposed was that the formation of tungsten carbide at 1100°F keyed the slip to increase the hardness. Bain also studied the crystal struc-

chemical engineering in 1908. His initial interest inmetallography began in a class where he saw photomicrographs of fer- rite, pearlite, and martensite. Bain would follow this field of science throughout his career. His first job after graduation was with the National Bureau of Standards in Washington. Aftera fewyears, he returned to Ohio State to work on an advanced degree, where he took the only course offered in metallography and metallurgy. Before he earned his master’s degree, his department head recommended him as an instructor at the University of Wiscon- sin teaching metallography and pyrome- try. Due to his limited knowledge, he first took a summer course in these subjects. He selected the laboratory course at

year, then accepted a research posi- tion at the B.F. Goodrich Co. When the U.S. entered WWI, Bain joined the army where he worked in chemical warfare research. After his discharge, he joined General Electric’s National Lamp Works where he worked under Zay Jeffries. His first assignment was to investi- gate the problem of failed dies of high- speed steel during the wire drawing of tungsten. He studied the mechanism of secondary hardening, which was still a mystery after 20 years of use. Bain and Jeffries published their results in a fa- mous paper on the “Red Hardness of High-Speed Steel” in Iron Age magazine in 1923. They combined the principles of precipitation hardening by Paul Dyer Merica with a mechanism of slip for rows of atoms to slide past one another for plastic deformation. The secondary

ture of metal solid solutions using x-ray diffraction, a new tool. Previous theory taught by Howe at Columbia and Al- bert Sauveur at Harvard stated there were patches of crystal structure of the solvent and other patches with the sol- ute. Bain’s results for copper and zinc (brass) showed for the first time that the solute atoms of a different crystal structure simply replaced solvent at- oms at random without changing the crystal structure. After four years of working with Jeffries at GE, Bain joined Atlas Steel in Dunkirk, N.Y., where he worked on high- speed and other alloy tool steels with Marcus Grossmann. This was an espe- cially productive time for Bain as he was now pursuing a career studying transfor- mation during steel heat treatment and the effect of alloy additions. Alloy steels were becoming ever more important with the expanded production of auto- mobiles and farm machinery, but un- derstanding heat treatment and alloying elements had made little progress. In July 1924, Bain joined the Union Carbide and Carbon Corp., a producer of ferroalloys including ferrochromium. During the summer of 1927, he took a leave from his work and visited steel plants, laboratories, and universities in Europe with Grossmann. They met with some early researchers who had done the first studies on tool steels, alloy steels, and the transformation of austenite.

American metallurgist Edgar C. Bain, of bainite fame. Courtesy of Library of Congress.

From left to right, Marcus Grossmann and Edgar Bain of Atlas Steel Corp., Dunkirk, N.Y., circa 1923. Courtesy of ASM.