Boron nitride insulating material

Patent · Sun Jan 01 00:00:00 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 (United States)
• 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

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