Developing into the future.
That was the premise of Professor Carl R. Loper, Jr. of the University of Wisconsin-Madison, who delivered the Edgar J. Hoyt Memorial Lecture at the 96th AFS Casting Congress.
"No aspect of the industry has escaped this far-reaching reformation," he said. "It has encompassed all metals cast, all processes of casting, management and marketing."
He cited the discovery of ductile iron and the advent of the Foundry Educational Foundation (FEF) as examples of the industry's coming of age.
Ductile iron marked the emergence of a new and revolutionary engineering material, while FEF revealed the industry was making an equally revolutionary commitment to generations of young people planning metalcasting careers.
Loper, who is a professor of materials science and engineering, said these two events served as postwar platforms to launch programs for the technological advancement of commercial casting production around the world.
"Today, we can look back on those events," he said, "and their near 45 years of existence, as examples to our industry in order to learn from them as we prepare for future foundry development and growth."
Discovery of Ductile Iron
Ductile iron was an intellectual achievement that changed the application of iron castings, according to Loper.
"Ductile cast iron was discovered through development carried out at the International Nickel Co. during the Second World War by Keith D. Millis and Albert P. Gagnebin," he noted.
Development of the iron began after chromium metal (an essential alloying agent) became scarce in the early years of the war. The process included adding zirconium, cerium, bismuth, copper, lead, tellurium, magnesium and columbium to a Ni-Hard base alloy.
Magnesium as a deoxidizer posed a problem because of its violent reaction to iron in the nickel-base alloy.
"However, as most researchers have to achieve experience one way or another," Loper said, "the experiment with magnesium was permitted to go ahead."
Surprisingly, it produced 5 in. of clear chill in a 6-in.-tall casting, with the remaining inch mottled.
The process was documented in February 1942 and eventually patented. In the next year, magnesium was tested in gray iron, and analysis showed excellent tensile properties and a microstructure that was entirely spheroidal.
Forty-four years ago, BCIRA made the first public disclosure of a procedure whereby flake graphite could be converted into spheroidal graphite in cast iron "through a process involving the treatment of low sulfur hypereutectic cast iron with cerium prior to casting."
Subsequent investigations showed that magnesium was equally effective in creating nodular graphite in gray iron, Loper said.
In the next decades, academic and practical studies were conducted on how nodule count, residual elements and sulfur affect the production of ductile iron. Research has delved into section size sensitivity, solidification control and monitoring, gating and risering, and proper equipment and processing.
DI Research Pendulum
Despite ductile iron's importance to U.S. and Canadian foundries, research data on the metal has been transferred from North America to other countries. This is confirmed by an analysis of the origin of investigative literature on the subject, according to Loper.
He said that from 1960-1990, the percentage of foreign authors of ductile iron papers in the AFS Transactions rose from 10.1% to 42.4%. Although this wasn't necessarily bad, it points to the increasing inadequacy of technical education and research in the U.S., Loper said.
One agent important to redressing this situation is FEF, which was established in 1947 to assure the inclusion of cast metal technology in the curricula of engineering schools, he said. FEF originally included five universities but has grown to include 29 institutions of higher education in its program.
The industry also is fortunate in that it has developed, nurtured and used a program of educational training and continuing education provided by the Cast Metals Institute, Loper said. The professor also cited the AFS chapters for recognizing education's importance.
The industry's future requires a positive response to the need for education in the industry, Loper said. It must provide opportunities for training as well as finding ways to encourage and provide the facilities for instruction.
He concluded by issuing a challenge to the industry: "Are the foundrymen of today prepared to provide the tools, train the people, develop and apply the technologies, and offer the leadership necessary to ensure when we look back at our development and growth 20 years from today, that it will show that the fruits of their vision were at least as successful as we have seen it today?"
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|Title Annotation:||96th AFS Casting Congress Milwaukee; ductile iron|
|Date:||Jun 1, 1992|
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