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Title: Measurement of Heat Flux at Metal-Mold Interface during Casting Solidification

Abstract

All previous studies on interfacial heat transfer coefficient have been based on indirect methods for estimating the heat flux that employed either inverse heat transfer analysis procedures or instrumentation arrangements to measure temperatures and displacements near the metal-mold interface. In this paper, the heat transfer at the metal-mold interfaces is investigated using a sensor for the direct measurement of heat flux. The heat flux sensor (HFS) was rated for 700oC and had a time response of less than 10 ms. Casting experiments were conducted using graphite molds for aluminum alloy A356. Several casting experiments were performed using a graphite coating and a boron nitride coating. The measurement errors were estimated. The temperature of the mold surface was provided by the HFS while the temperature of the casting surface was measured using a thermocouple. Results for the heat transfer coefficients were obtained based on measured heat flux and temperatures. Four stages were clearly identified for the variation in time of the heat flux. Values of the heat transfer coefficient were in good agreement with data from previous studies.

Authors:
 [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1003632
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: International Journal of Cast Metals Research; Journal Volume: 19; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALLOYS; ALUMINIUM; BORON NITRIDES; CASTING; COATINGS; GRAPHITE; HEAT FLUX; HEAT TRANSFER; SOLIDIFICATION

Citation Formats

Sabau, Adrian S. Measurement of Heat Flux at Metal-Mold Interface during Casting Solidification. United States: N. p., 2006. Web. doi:10.1179/136404606225023390.
Sabau, Adrian S. Measurement of Heat Flux at Metal-Mold Interface during Casting Solidification. United States. doi:10.1179/136404606225023390.
Sabau, Adrian S. Sun . "Measurement of Heat Flux at Metal-Mold Interface during Casting Solidification". United States. doi:10.1179/136404606225023390.
@article{osti_1003632,
title = {Measurement of Heat Flux at Metal-Mold Interface during Casting Solidification},
author = {Sabau, Adrian S},
abstractNote = {All previous studies on interfacial heat transfer coefficient have been based on indirect methods for estimating the heat flux that employed either inverse heat transfer analysis procedures or instrumentation arrangements to measure temperatures and displacements near the metal-mold interface. In this paper, the heat transfer at the metal-mold interfaces is investigated using a sensor for the direct measurement of heat flux. The heat flux sensor (HFS) was rated for 700oC and had a time response of less than 10 ms. Casting experiments were conducted using graphite molds for aluminum alloy A356. Several casting experiments were performed using a graphite coating and a boron nitride coating. The measurement errors were estimated. The temperature of the mold surface was provided by the HFS while the temperature of the casting surface was measured using a thermocouple. Results for the heat transfer coefficients were obtained based on measured heat flux and temperatures. Four stages were clearly identified for the variation in time of the heat flux. Values of the heat transfer coefficient were in good agreement with data from previous studies.},
doi = {10.1179/136404606225023390},
journal = {International Journal of Cast Metals Research},
number = 3,
volume = 19,
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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