ZG
supplies
custom
Metalized
Alumina
Ceramics
engineered
for
demanding
applications
requiring
high
vacuum,
high
voltage,
and
high
pressure
performance.
These
precision
metallized
ceramics
serve
as
critical
components
in
power
grid
tubes,
vacuum
interrupters,
RF
windows,
metallized
rings,
and
various
specialized
insulators
and
sensors.
Material
Properties
Alumina
stands
as
one
of
the
most
widely
utilized
engineering
ceramic
materials,
delivering
exceptional
hardness,
superior
wear
resistance,
and
outstanding
electrical
insulation
characteristics.
Our
high-purity
alumina
ceramics
(94-96%
Al₂O₃)
form
the
foundation
of
our
products,
with
alternative
ceramic
materials
available
to
meet
specific
application
requirements.
Manufacturing
Process
Our
standard
metalized
alumina
ceramics
employ
molybdenum-based
paints
followed
by
precision
nickel
plating.
A
specialized
coating
formulation
containing
molybdenum
and
manganese
particles
combined
with
glass
additives
and
volatile
carriers
is
meticulously
applied
to
the
ceramic
surface
through
hand-painting,
spraying,
or
robotic
application
methods.
Following
air
drying,
the
coating
undergoes
controlled
firing
in
a
wet
hydrogen
environment
at
temperatures
ranging
from
1450°-1600°C.
This
process
yields
a
robust
"glassy"
metallic
coating
measuring
300-500
micro-inches
(7.6-12.7
microns)
thick,
ensuring
exceptional
bond
strength
between
the
metallized
layer
and
ceramic
substrate.
The
fired
coating
is
subsequently
plated
with
a
0.001-0.003
inch
(25.4-76.2
microns)
nickel
layer.
The
nickel
plating
undergoes
sinter-firing
at
850-950°C
in
a
dry
hydrogen
atmosphere,
producing
a
finished
metallic
surface
optimized
for
brazing
with
standard
braze
filler
metals.
Advantages
of
Ceramics
-
Low
dielectric
loss
with
optimal
dielectric
constant
-
High
thermal
conductivity
for
efficient
heat
dissipation
-
Compatible
thermal
expansion
coefficients
between
ceramics
and
metals
-
Exceptional
bonding
strength
between
metal
layer
and
ceramic
substrate
-
High
operating
temperature
capability,
withstanding
extreme
temperature
cycles
and
normal
operation
at
500-600°C
-
Superior
electrical
insulation
properties
with
high
breakdown
voltage
resistance
Technical
Specifications
|
Tensile
Strength,
Kovar
Cup
Method
|
>
20,000
psi,
avg.
(138N/mm²)
|
|
Helium
Leak
Rate
|
<
10⁻⁹
cc/sec
|
|
Thermal
Shock
Resistance
(room
temperature
to
850°C)
|
Will
not
burst
or
leak
after
five
operations
|
Product
Gallery
