Allvac, an Allegheny Technologies Incorporated company, and joint recipient General Electric Company Corporate Research and Development have been awarded a contract to develop a new technology to enable the production of very large nickel-based superalloy ingots required for the next generation of high-efficiency land-based turbines for power generation. The contract was awarded by the Advanced Technology Program (ATP) of the National Institute of Standards and Technology (NIST), a US Department of Commerce programme. The research effort will be directed toward the development of Clean Metal Nucleated Casting (CMNC), a new processing technology for the efficient casting of large, fine-grained, segregation-free superalloy ingots. The research program began on 1 November 2001 and will continue for a period of four years.
“High efficiency gas turbines are among the most demanding applications for modern metallurgy,” said Jack W. Shilling, Allegheny Technologies executive vice president, strategic initiatives and technology and chief technology officer. “The trend in turbines is toward more efficient designs, which means operating temperatures in excess 600 degrees C. If successful, CMNC is expected to change the process for the casting of superalloys from one of liquid metal processing to one of casting in the semi-solid state, thereby enabling large gains in productivity, small grain size, and compositional uniformity. To work, the liquid metal must be free of oxide contaminants that are commonly introduced by erosion of high-temperature ceramic components used in conventional casting.”
