Rapid Solidification Processing and Powder Metallurgy of Al Alloys.
Abstract
During the second year of the program, there have been five areas of emphasis. These are: 1) the development of a model to describe the mechanism of formation of rapidly solidified Al alloys (i.e. zones A and B); ii) the processing of particulate whose microstructure consists entirely of zone A; iii) the microstructures of rapidly solidified particulate of alloys based on Ai-8Fe; iv) the identification of metastable phases which form in some of the Al alloys studied; and v) dynamic compaction of particulate. A simple model for the formation of rapidly solidified hyper-eutectic Al alloys has been developed. This model is based on the degree of undercooling achieved prior to nucleation and the extent to which recalescence effects may be inhibited by a rapid rate of heat-extraction. Zone A microstructures form when the temperature is lowered to below that of the extended alpha-Al liquidus where primary Al may be nucleated. The microstructures of rapidly solidified Al-Ni and Al-Co alloys may be interpreted satisfactorily by this model.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 29, 1984
- Accession Number
- ADA148427
Entities
People
- H.L. Fraser
Organizations
- University of Illinois Urbana–Champaign