Boron nitride insulating material

Patent · Sun Jan 01 04:00:00 EST 1978

OSTI ID:863153

Cavin, O Burl ^[1]; McCulloch, Reginald W ^[2]; Clark, David L ^[3]

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1. Knoxville, TN
2. Concord, TN
3. Clearwater, FL

High temperature BN-insulated heaters for use as fuel pin simulators in reactor thermal hydraulic test facility studies comprise a cylindrical housing and a concentric heating element disposed within the housing and spaced apart from the housing to define an annular region therebetween. The annular region contains BN for providing electrical resistance and thermal conductivity between the housing and the heating element. The fabrication method of this invention comprises the steps of cold pressing BN powder at a pressure of 20 to 80,000 psig and a dwell time of at least 0.1-3 seconds to provide hollow cylindrical preforms of suitable dimensions for insertion into the annular region, the BN powder having a tap density of about 0.6-1.1 g/cm.sup.3 and an orientation ratio of at least about 100/3.5. The preforms are inserted into the annular region and crushed in place.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4106186
• OSTI ID: 863153
• Country of Publication: United States
• Language: English

Related Subjects

/29/219/264/338/
000
1-3
100
20
6-1
80
annular
annular region
apart
bn
bn-insulated
boron
boron nitride
cm
cold
cold pressing
comprise
comprises
concentric
conductivity
contains
crushed
cylindrical
cylindrical housing
define
density
dimensions
disposed
dwell
dwell time
electrical
electrical resistance
element
element disposed
fabrication
fabrication method
facility
fuel
heaters
heating
heating element
hollow
hollow cylindrical
housing
hydraulic
inserted
insertion
insulating
insulating material
material
method
nitride
orientation
powder
preforms
pressing
pressure
provide
providing
providing electrical
psig
ratio
reactor
reactor thermal
region
resistance
simulators
spaced
spaced apart
steps
studies
suitable
tap
temperature
temperature bn
therebetween
thermal
thermal conductivity
thermal hydraulic
time