Accession Number:

ADA188682

Title:

Development of Metastable Processing Paths for High Temperature Alloys

Descriptive Note:

Annual technical rept. 9 Feb-30 Sep 1987

Corporate Author:

NATIONAL BUREAU OF STANDARDS GAITHERSBURG MD METALLURGY DIV

Personal Author(s):

• Boettinger, William J.

Report Date:

1987-09-30

Pagination or Media Count:

40.0

Abstract:

The possibility of developing new processing strategies for high temperature intermetallic compounds is being investigated. In particular rapid solidification followed by controlled heat treatment may provide new and unusual microstructures of multiphase materials. This report describes research performed at NBS to develop predictive models for solubility extension and metastable phase formation of intermetallic compounds and research to improve the phase diagram modeling of systems involving ordered phases. Theory has been clarified to treat the interface shape stability for intermetallic compounds during solidification. Using modified variables to describe the phase diagram near an intermetallic compound the solidification conditions required to avoid microsegregation have been obtained. Experimental research has been conducted on three intermetallic systems, Aluminum niobium, Nickel aluminum-nickel titanium, and Titanium aluminum to gain experimental data base for theoretical model development using melt spinning and examination by transmission electron microscopy.

Descriptors:

• *ALUMINUM ALLOYS
• *INTERMETALLIC COMPOUNDS
• *NICKEL
• *NIOBIUM
• *PROCESSING
• *TITANIUM
• CONTROL
• ELECTRON MICROSCOPY
• EXPERIMENTAL DATA
• GAIN
• HEAT RESISTANT ALLOYS
• HEAT TREATMENT
• HIGH TEMPERATURE
• INTERFACES
• MATERIALS
• MELTS
• METASTABLE STATE
• MICROSTRUCTURE
• MODELS
• PATHS
• PHASE
• PHASE DIAGRAMS
• PREDICTIONS
• QUICK REACTION
• SHAPE
• SOLIDIFICATION
• SOLUBILITY
• SPINNING(INDUSTRIAL PROCESSES)
• STABILITY
• STRATEGY
• THEORY
• TRANSMITTANCE

Subject Categories:

• Fabrication Metallurgy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE