Grain Refinement through Thermal Cycling in an Fe-Ni-Ti Cryogenic Alloy.
Abstract
A thermal cycling technique which allows the grain refinement of Fe-12Ni-0.25Ti alloy in four cycles has been developed. The process consists of alternate annealing in gamma range and (alpha + gamma) range with intermediate air cooling. The transformation, microstructures and cryogenic mechanical properties on each cycling step are described. Due to the ultrafine grain size, the ductile-brittle transition temperature of this ferritic alloy in Charpy impact testing was suppressed below 6K. In fracture toughness testing at 77K, the mode of fracture was altered from brittle quasi-cleavage to complete ductile rupture through the grain refining. (Modified author abstract)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1974
- Accession Number
- AD0775510
Entities
People
- J. W. Morris Jr.
- Shilei Jin
- V. F. Zackay
Organizations
- University of California, Berkeley