IPC-TM-650 EN 2022 试验方法-- - 第715页

IPC-TM-650 Page 2 of 2 Number 2.6.11.1 Revision Subject Hydrolytic Stability - Conformal Coating Date 07/00 5.2 Evaluation 5.2.1 During testing, examine the test specimens at 28th, 56th and 84th days. Prior to examining …

100%1 / 824
IPC-CC-830
FED-STD-141
Note:
75 mm
[2.95 in]
4.7 mm
[0.185 in]
38 mm
[1.50 in]
19 mm
[0.748 in]
6.30 mm [0.248 in]
2.3
0.13 mm DIA
[0.091
0.005 in DIA]
Hole 0.75
0.08 mm DIA
[0.029
0.003 in DIA]
0.75 mm [0.029 in MIN]
0.75 mm
008 mm [0.029 in 0.003 in MIN]
0.75 mm [0.029 in MIN]
3.2 mm
[0.126 in]
25
1.5 mm
[0.984
0.059 in MIN]
3.8
0.13 mm DIA
[0.150
0.005 in DIA]
HOLE 1.3
0.08 mm DIA
[0.051
0.0031 in DIA]
Figure 1 ‘‘Y’’ Shape Pattern
Material in this Test Methods Manual was voluntarily established by Technical Committees of IPC. This material is advisory only
and its use or adaptation is entirely voluntary. IPC disclaims all liability of any kind as to the use, application, or adaptation of this
material. Users are also wholly responsible for protecting themselves against all claims or liabilities for patent infringement.
Equipment referenced is for the convenience of the user and does not imply endorsement by IPC.
Page 1 of 2
Number
r
ASSOCIATION
CONNECTING
/
ELECTRONICS
INDUSTRIES
221
5
Sanders
Road
Northbrook,
IL
60062-6135
IPC-TM-650
TEST
METHODS
MANUAL
1
Scope
This
test
method
is
to
determine
the
resistance
of
the
applied
conformal
coating
to
reverting
to
liquid
when
exposed
to
high
humidity
at
a
specific
temperature
and
time
condition
for
each
class.
This
test
method
is
to
evaluate
the
quality
of
the
coated
printed
boards
under
storage
conditions
(nonoperating).
2
Applicable
Documents
Qualification
and
Performance
of
Electrical
Insu¬
lating
Compound
for
Printed
Board
Assemblies
Method
4061
(Dry-Through
For
Varnish,
Lac¬
quers
And
Enamels)
3
Test
Specimens
Five
coated
shape
patterns
(see
Figure
1)
containing
two
resistors,
one
with
marking
ink
and
one
with
color
code
bars,
coated
with
conformal
coating
per
the
coating
supplier's
recommendations.
2.6.11.1
(Supersedes
2.6.1
1B
for
Conformal
Coating
Test)
Subject
Hydrolytic
Stability
-
Conformal
Coating
Date
07/00
Revision
Originating
Task
Group
Conformal
Coating
Task
Group
(5-33a)
4
Equipment
4.1
Desiccator
At
least
25
cm
[9.84
in]
in
diameter
4.2
Potassium
Sulfate
Reagent
grade
potassium
sulfate
4.3
Cotton
Swabs
4.4
Oven
Capable
of
maintaining
temperature
up
to
1
00℃
[212°F]-
4.5
Test
Chamber
Capable
of
maintaining
a
constant
tem¬
perature
of
85°
±
2
℃
[185°
±
3.6°F]
with
95
±
4%
relative
humidity
4.6
Soldering
Iron
If
applicable
4.7
High
Temperature
Silicone
Grease
5
.0
Procedures
5.1
Desiccator
Method
5.1.1
Prepare
a
saturated
solution
of
distilled
or
deionized
water
and
potassium
sulfate
(35
grams
per
100
cm3)
at
a
temperature
of
85°
土
2
℃
[185°
±
3.6°F].
Pour
the
solution
into
the
desiccator
just
below
the
ceramic
plate.
Crystals
of
potassium
sulfate
should
remain
visible
in
the
saturated
solu¬
tion
during
testing.
Relative
humidity
is
not
to
exceed
98%.
5.1.2
Place
four
of
the
five
test
specimens
on
the
ceramic
plate
in
the
desiccator
so
that
they
are
not
touching
each
other.
The
fifth
specimen
is
used
as
a
control.
5.1.3
Seal
the
desiccator
with
high
temperature
silicone
grease
and
close
the
desiccator.
5.1.4
Place
the
desiccator
in
the
oven
maintained
at
85°
±
2
℃
[185°
土
3.6°F].
5.1.5
Allow
the
desiccator,
containing
the
test
specimens,
to
remain
in
the
oven
for
1
20
days.
IPC-TM-650
Page 2 of 2
Number
2.6.11.1
Revision
Subject
Hydrolytic
Stability
-
Conformal
Coating
Date
07/00
5.2
Evaluation
5.2.1
During
testing,
examine
the
test
specimens
at
28th,
56th
and
84th
days.
Prior
to
examining
the
test
specimens,
they
shall
be
returned
to
25℃
[77°F]
and
50%
relative
humid¬
ity
for
two
hours.
Evaluate
the
specimens
for
evidence
of
reversion
as
indicated
by
softening,
chalking,
blistering,
crack¬
ing,
tackiness,
loss
of
adhesion
or
liquefaction.
Evaluate
also
legibility
of
the
markings
on
the
board
and/or
the
resistors.
5.2.2
After
the
1
20-day
aging
period,
the
panels
shall
be
returned
to
25℃
[77°F]
and
50%
relative
humidity
and
held
for
seven
days.
The
specimens
shall
be
evaluated
and
compared
with
the
control
specimen
as
per
5.2.1.
The
specimens
shall
also
be
tested
for
tackiness
in
accordance
with
Method
4061
(Dry-Through
For
Varnish,
Lacquers
And
Enamels)
of
FED-
STD-141.
5.3
Chamber
Method
5.3.1
Place
four
of
the
five
test
specimens
into
the
test
chamber,
by
placing
them
in
a
rack
or
hanging,
so
that
they
do
not
touch
each
other.
The
fifth
specimen
is
held
as
a
con¬
trol.
Close
the
chamber
door.
5.3.2
Set
the
chamber's
parameters
at
85°
±
2
℃
[185°
±
3.6°F]
and
95
±
4%
relative
humidity.
Activate
the
test
cham¬
ber
and
begin
testing.
5.3.3
Allow
the
specimens
to
remain
in
the
test
chamber
for
1
20
days.
5.4
Evaluation
5.4.1
During
testing,
examine
the
test
specimens
at
28th,
56th
and
84th
days.
Prior
to
examining
the
test
specimens,
they
shall
be
returned
to
25℃
[77°F]
and
50%
relative
humid¬
ity
for
two
hours.
Evaluate
the
specimens
for
evidence
of
reversion
as
indicated
by
softening,
chalking,
blistering,
crack¬
ing,
tackiness,
loss
of
adhesion
or
liquefaction.
Evaluate
also
legibility
of
the
markings
on
the
board
and/or
the
resistors.
5.4.2
After
the
1
20-day
aging
period,
the
panels
shall
be
returned
to
25℃
[77°F]
and
50%
relative
humidity
and
held
for
seven
days.
The
specimens
shall
be
evaluated
and
compared
with
the
control
specimen
as
per
5.2.1
.
The
specimens
shall
also
be
tested
for
tackiness
in
accordance
with
Method
4061
(Dry-Through
For
Varnish,
Lacquers
And
Enamels)
of
FED-
STD-141.
IPC-TR-476
MIL-P-55110
Figure 1
The Institute for Interconnecting and Packaging Electronic Circuits
2215 Sanders Road • Northbrook, IL 60062-6135
Material in this Test Methods Manual was voluntarily established by Technical Committees of the IPC. This material is advisory only
and its use or adaptation is entirely voluntary. IPC disclaims all liability of any kind as to the use, application, or adaptation of this
material. Users are also wholly responsible for protecting themselves against all claims or liabilities for patent infringement.
Equipment referenced is for the convenience of the user and does not imply endorsement by the IPC.
Page 1 of 2
回
IPC-TM-650
TEST
METHODS
MANUAL
Number
2.6.13
Subject
Assessment
of
Susceptibility
to
Metallic
Dendritic
Growth:
Uncoated
Printed
Wiring
Date
Revision
10/85
Originating
Task
Group
N/A
1
.0
Scope
This
test
method
will
demonstrate
a
relative
degree
to
which
uncoated
printed
wiring
boards
are
suscep¬
tible
to
dendritic
growth
due
to
the
presence
of
ionic
residues
and
condensed
moisture.
This
test
method
is
particularly
suit¬
able
for
printed
wiring
board
manufacturing
process
control.
2
.0
Applicable
Documents
How
to
Avoid
Metallic
Growth
Problems
on
Electronic
Hardware
Printed
Wiring
Boards
3
.0
Test
Specimens
Test
pattern
is
chosen
from,
but
not
restricted
to
e.g.,
MIL-P-551
10
type
"Y”
pattern
with
a
pair
of
conductors
having
typically
15-30
mils
separation
(See
Figure
1).
A
pair
of
parallel
conductors
on
an
uncoated
production
printed
wiring
board,
with
spacing
between
conductors
of
approximately
15-30
mils
is
suitable
as
well.
4
.0
Equipment/Apparatus
4.1
Power
Supply
A
de
power
supply
capable
of
providing
a
metered
0-20
V
de,
and
100
milliamps
current.
4.2
Microscope
50-100
power
microscope
and
means
of
providing
direct
and/or
indirect
lighting
on
specimen.
4.3
Miscellaneous
Items
DI
water
sample
(2
o
乙)
kept
in
a
plastic
bottle,
eye
dropper,
a
1/2
watt-
1
0K
ohm
current
limit¬
ing
resistor
and
a
stop
watch.
5
.0
Procedure
5.1
Preparation
5.1.1
Attach
a
wire
to
each
of
the
conductors
on
the
"Y”
pattern
test
board,
or
to
corresponding,
parallel
conductors
on
a
production
PWB.
5.1.2
Connect
a
10K
resistor
in
series
to
the
power
supply
as
shown
in
Figure
1.
The
resistor
will
limit
the
current
to
1
.5
milliamp
maximum.
5.1.3
Place
the
board
for
viewing
on
the
microscope,
so
that
the
parallel
conductors
are
in
view.
Provide
lighting
that
will
illuminate
the
test
board
on
top
and/or
underneath.
5.1.4
Using
the
eye
dropper,
place
a
drop
of
DI
water
across
the
conductors
that
are
in
view
under
the
microscope,
at
least
0.5
inch
away
from
the
place
where
external
wires
are
attached
to
parallel
conductors.
Adjust
power
supply
to
15
V
and
turn
the
power
supply
on.
Simultaneously
start
the
stop¬
watch.
5.1.5
Carefully
observe
the
action
using
the
microscope.
Adjust
the
power
of
the
microscope
so
the
entire
water
area
is
in
view.
5.1.6
Bubbles
may
appear
within
about
5
seconds.
This
is
hydrogen
evolution-electrolysis
of
water.
5.1.7
Depending
on
PWB
ionic
cleanliness
level
and
the
characteristics
of
the
PWB
surface,
there
may
be
a
dendritic
(tree-like)
growth
from
the
negative
to
positive
conductor,
appearing
within
a
typical
(for
a
given
board)
but
generally
very
broad
time
span
of
a
few
seconds
to
several
minutes.
5.1.8
The
condition
of
dendritic
growth
is
much
easier
to
observe
with
an
artificial
light
source
placed
under
the
test
board.
A
clear
demonstration
of
the
dendritic
growth
can
be
performed
if
tap
water
containing
ionic
contamination
is
used
in
place
of
DI
water
(see
paragraph
5.1
.4).
5.1.9
Once
the
dendritic
growth
has
reached
the
positively
charged
conductor,
most
action
will
cease;
turn
off
the
stop¬
watch.
The
elapsed
time
is
a
relative
measure
of
susceptibility
of
the
PWB
in
question
to
undergo
dendritic
growth
under
high
humidity
(condensed
moisture)
environment.
At
least
ten