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Title: Modeling and processing of liquid-phase-sintered γ-TiAl during high-density infrared processing

Abstract

A new method for the rapid processing of thin gage sheet of traditionally difficult-to-process materials, such as y-TiAl, has been modeled and experimentally developed. The method uses high density infrared (HDI) rapid heating of a plasma arc lamp to liquid-phase sinter powder metal compact precursors to structures of varying densities. Material properties for precursor y-TiAl compacts were effectively chosen or determined and then used with a finite-volume heat-transfer modeling code to model the process. With the aid of the model, processing parameters were determined that allowed for a temperature gradient across the sheet that would produce a liquid-phase cast structure on the surface, residual powder on the backside, and a middle layer solid + liquid zone. Temperature and phase fields were predicted through the thickness of the sheet using the model. Fine grain, lamellar structured materials were produced in the liquid-phase-sintered zone.

Authors:
 [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
1003633
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Metallurgical and Materials Transactions A; Journal Volume: 37; Journal Issue: 4
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; HEAT TRANSFER; HEATING; LIGHT BULBS; PLASMA; PRECURSOR; PROCESSING; SIMULATION; TEMPERATURE GRADIENTS; THICKNESS

Citation Formats

Sabau, Adrian S, and Blue, Craig A. Modeling and processing of liquid-phase-sintered γ-TiAl during high-density infrared processing. United States: N. p., 2006. Web.
Sabau, Adrian S, & Blue, Craig A. Modeling and processing of liquid-phase-sintered γ-TiAl during high-density infrared processing. United States.
Sabau, Adrian S, and Blue, Craig A. Sun . "Modeling and processing of liquid-phase-sintered γ-TiAl during high-density infrared processing". United States. doi:.
@article{osti_1003633,
title = {Modeling and processing of liquid-phase-sintered γ-TiAl during high-density infrared processing},
author = {Sabau, Adrian S and Blue, Craig A},
abstractNote = {A new method for the rapid processing of thin gage sheet of traditionally difficult-to-process materials, such as y-TiAl, has been modeled and experimentally developed. The method uses high density infrared (HDI) rapid heating of a plasma arc lamp to liquid-phase sinter powder metal compact precursors to structures of varying densities. Material properties for precursor y-TiAl compacts were effectively chosen or determined and then used with a finite-volume heat-transfer modeling code to model the process. With the aid of the model, processing parameters were determined that allowed for a temperature gradient across the sheet that would produce a liquid-phase cast structure on the surface, residual powder on the backside, and a middle layer solid + liquid zone. Temperature and phase fields were predicted through the thickness of the sheet using the model. Fine grain, lamellar structured materials were produced in the liquid-phase-sintered zone.},
doi = {},
journal = {Metallurgical and Materials Transactions A},
number = 4,
volume = 37,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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