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The History of Alloy Steels: Part I The widespread use of alloy steels beginning in the early 1900s spurred the need to acquire and share information about heat treating, Metallurgy Lane, which previously had been a guarded art. authored by ASM life member arbon is the single most potent element years before anyone else entered the field. For his Charles R. Simcoe, added to iron, even though it is not work in developing alloy steel and related heat is a yearlong series Cthought of as an alloy because the word treatments and applications, Brustlein deserves dedicated to the early “steel” is defined as carbon in iron. Amounts as to be called the Father of Alloy Steels. history of the U.S. metals small as 0.05% have profound effects on the behav- and materials industries ior of iron, and 0.15 to 0.25% additions are suffi- Nickel steel development along with key cient to make mild structural steel. Most heat While Brustlein was developing chromium milestones and treated alloy steels contain 0.30 to 0.40% C. Carbon steels, other French metallurgists were learning developments. has two characteristics that account for its power- to smelt nickel-containing ore from New Cale- ful effects from such small amounts: It is very low donia, a French territory in the South Pacific. in density, so therefore a great number of atoms are The resulting ferronickel was then used to add present in small amounts (by weight), and its atoms nickel to steel. The production of nickel steel was are smaller than iron atoms, so they do not substi- observed in France in 1888 by James Riley, an tute for iron in the crystal lattice, but take up a Englishman who made arrangements for similar unique position in the holes between the iron steels to be made at The Steel Company of Scot- atoms. It is this interstitial position of carbon atoms land in 1889. He immediately tested these steels in the iron lattice—along with the crystal lattice and reported their properties in the Journal of transformation from face centered cubic (fcc) to the Iron and Steel Institute. One of his steels con- body centered cubic (bcc) on cooling—that makes taining roughly 0.2% C and 5% Ni developed steel such a marvelous material for construction, strength properties of considerable interest for power transmission, and tools in the modern era. many different structural and machine applica- The first alloy steel contained chromium and tions. This steel, processed by rolling and an- was patented in 1865 by American metallurgist nealing, was about 40% stronger than similar Julius Baur and manufactured by the Chrome Steel steel without nickel. Co. of Brooklyn, N.Y. The first alloy steel employed in regular indus- This alloy steel was trial production in the U.S. was 5% nickel steel, never successful, but the used for bicycle chains (1898), followed the next publicity prompted an year by bicycle tubing. The first use of alloy steel in interest in chromium the emerging automotive industry was a 5% nickel alloy steels by French steel axle by Haynes and Apperson. Somewhat metallurgist Henri-Ami later, nickel steels (3.5%) became popular for the Brustlein. He soon structural components of large bridges, including learned that to alloy the Manhattan and Queensboro Bridges in New chromium with steel, York City. In 1900, about 3000 tons of alloy steel the chromium ore were produced in the U.S. needed to be refined to Shortly after nickel steels came into use, more produce a master alloy complex alloy steels containing both chromium of iron-chromium-car- and nickel were being tested by Krupp in Germany bon. This master alloy and by the Compagnie des Forges de la Marine in would readily dissolve France. These nickel-chromium steels could be The first use of alloy into the melt of the cru- hardened in large sections by heat treating so they steel in the U.S. was for cible process, otherwise the recovery of became very popular for armor and large forgings. the axle of the famous chromium would be too erratic to control the After the turn of the century, the straight nickel Ferris Wheel at the 1893 alloy content. Brustlein produced and sold steels rapidly declined in use in favor of the nickel- Chicago World’s Fair. Courtesy of Library of chromium alloy steels for tools, cannon shells, chromium steels and the newly developed Congress. and armor plate over a period of about 15 to 20 chromium-vanadium steels.

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Henry Louis Le Chatelier of France developed high-temperature platinum- platinum/rhodium Queensboro Bridge made of nickel steel, New York City, circa 1908. Courtesy of Library of Congress. thermocouples, useful for measuring Automobiles usher in alloy steel era critical temperatures in steel. It was the automobile that initiated the Age of Alloy Steel. The number of alloy steels used in the auto industry increased throughout the decade of 1910-1920. Walter Jominy, a metallurgist from the University of Michigan who worked for the Stude- baker Automobile Co., published a list of 12 alloy steels in 1920 that he said filled all the needs for building automobiles. World War I provided additional emphasis on the use of alloy steels and on the process of heat treat- ment. The quantity of alloy steel made in the U.S. Henry Clifton Sorby of England, an early reached more than 1 million tons in 1918, and the pioneer of widespread use of alloy steel increased the need to Bicycles at the turn of the century used 5% nickel steel in metallography. both acquire and share information about heat treat- their chains, the first widespread industrial use of an alloy Courtesy of steel. Courtesy of State Library of Queensland. ing, which previously had been a guarded art. University of Sheffield. William Park Woodside, a former blacksmith, began nal of the Iron and Steel Institute of Great Britain. holding meetings in Detroit to exchange information Their work reawakened Sorby’s interest in an area among heat treaters in the early auto industry. These he had worked on more than 20 years earlier. Sorby meetings lead to the formation of a formal group immediately began a new examination of the mi- called the Steel Treaters Club, which eventually be- crostructure of steels. He published his work in the came the American Society for Steel Treating. British Journal of the Iron and Steel Institute in 1887. These early groups formed chapters in various in- This new work by Sorby, along with that of Osmond dustrial regions across the country and published and Martens, is considered the true beginning of the data sheets on the technical aspects of heat treating. field of metallography, the study of the internal Soon they provided a publication called Transactions structure of metals. From this point forward, the for serious researchers to publish their papers. In ever increasing research into how the behavior of 1930, the American Society for Steel Treating pub- metals relates to their structure has been the foun- lished a magazine called Metal Progress (now Ad- dation of our modern technological age. vanced Materials & Processes). It became the most A second major development at this time was a popular source of information in all of metalworking, new measuring tool for high temperatures invented not just heat treating. The society changed its name by Henry Louis Le Chatelier of France, which used in the early 1930s to the American Society for Met- platinum-platinum/rhodium thermocouples. Os- als and later to ASM International. mond immediately put the new thermocouple to use in measuring the so called critical temperatures in The early science of steel steel. These temperatures—where changes were The first interest in examining the nature of steel noted in the rates of cooling or heating—were first came just after the midpoint of the 19th century. pointed out by Russian metallurgist D.K. Tchernoff. Henry Clifton Sorby of Sheffield, England, exam- He stated that steel could not be hardened upon For more ined polished and etched surfaces of meteorites and quenching until it was first heated above the upper- information: several commercial steels during 1863-1866. Sorby most critical temperature. These temperatures were Charles R. Simcoe discovered that the microstructure of steel was believed to represent important internal changes in can be reached at [email protected]. complex and he found an area that he called steel. The study of critical temperatures as a function For more metallurgical “pearly.” Later, Floris Osmond of France and Adolf of a steel’s carbon content lead to the field of binary history, Martens of Germany published their examination phase diagrams, which was the next advance in un- visit metals- of polished and etched surfaces of steel in the Jour- derstanding the complexity of steel. history.blogspot.com.

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