RESEARCH DIRECTED TOWARD THE DEVELOPMENT OF A WROUGHT SUPERALLOY.
Abstract
A program was initiated to develop a wrought alloy with superior properties at 1600 F for utilization in turbine wheel applications. The approach taken was to determine the kind and amount of alloying elements needed to produce the desired target requirements in a nickel or cobalt base system. The mechanical property goals at 1600 F included a tensile strength of 150,000 psi and a rupture life of 100 hours with an applied stress of 70,000 psi. Through the addition of varying amounts of numerous alloying elements in both simple and complex analyses it was possible to formulate a nickel base alloy with strength capabilities significantly better than the strongest wrought commercial alloys available with satisfactory ductility. The alloy developed contains significant quantities of molybdenum, tungsten, and tantalum in combination with aluminum and titanium in proportions that contributed to solid solution strengthening, gamma prime precipitation and stable carbide formations without producing excessive amounts of intermetallic phases in undesirable morphologies. The alloy also shows good thermal stability at 1600 F for times up to 2000 hours and in addition exhibits oxidation characteristics comparable with a number of commercial nickel base alloys. Although not meeting completely the target requirements of the program, the alloy offers considerable promise if additional work is conducted to optimize fabrication, strength and stability characteristics on a commercial size basis. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1966
- Accession Number
- AD0807290
Entities
People
- F. J. Rizzo
- L. W. Lherbier