IPC-TM-650 EN 2022 试验方法--.pdf - 第653页

specimen between layers of absorbent paper and r oll three or four times. Re peat until there i s no apparent absorption by the paper. Place immediately into the tared weighing bottle, cover the bottle, weigh and record …

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1 Scope
This test method defines the procedures to deter-
mine the moisture absorption properties of metal clad or
unclad flexible dielectrics.
2 Applicable Documents
None
3 Test Specimen
Prepare three specimens 10 cm x 10 cm
[approx.4 in x 4 in].
4 Apparatus
4.1 Test Chamber
Oven capable of maintaining the speci-
men at 105 - 110 °C [221 - 230 °F].
4.2 Analytical Balance
Analytical balance having an accu-
racy of ± 0.001 gram.
4.3 Miscellaneous
4.3.1
Vessel for holding distilled water
4.3.2
Etcher
4.3.3
Chemical etchants
4.3.4
Desiccator - Capable of holding 30% RH at 23 °C ±
2 °C [73.4 °F ± 3.6 °F]
4.3.5
40 mm dia. x 125 mm long (minimum size) glass-
stoppered evaluating bottles
4.3.6
Absorbent, lint-free paper
4.3.7
25-30 mm [approx. 5-6 in] wide, 25 mm [approx.1 in]
diameter, elastomeric (70-80 durometer hardness Shore A)
roller
4.3.8
Dry polyethylene film that is cut larger in size than
work area
4.3.9
Hard, flat, non-absorbent surface (e.g., plate glass)
4.3.10
Distilled Water
4.3.11
Thermometer for distilled water
5 Procedure
5.1 Preparation
5.1.1
If the specimen under test is a metal clad dielectric,
proceed to 5.1.2. If it is an adhesive coated dielectric, lami-
nate it with a release sheet next to adhesive or laminate to
copper foil using time, temperature, and pressure, which will
impart a normal state of cure to the adhesive. If the specimen
is a bare dielectric, proceed directly to 5.1.3.
5.1.2
Etch away all copper from the specimen using the
chemical etchants and etcher and wash thoroughly with dis-
tilled water.
5.1.3 Weighing Bottle Tare Weight
Dry a weighing bottle
and its glass stopper for each specimen at 105 °C - 110 °C
[221 °F - 230 °F] for a minimum of one hour. Immediately
place both the bottle and its stopper in a desiccator, allow
both to cool to room temperature, stopper the bottle and then
weigh and record to nearest 0.001 gram. Return each stop-
pered weighing bottle to desiccator.
5.2 Test
5.2.1
Dry the specimen(s) from 5.1.3 in an oven at 105 °C -
110 °C [221 °F - 230 °F] for one hour ± 5 minutes. Place each
specimen in a tared weighing bottle, re-stopper and then
weigh to nearest 0.001 gram. Repeat the drying cycle at least
once or until constant weight is reached. Record this constant
weight. Return weighing bottles to desiccator.
5.2.2
Immerse the specimen for 24 hours - 0 minutes/+30
minutes in a container filled with distilled water at a tempera-
ture of 23 °C ± 2 °C [73.4 °F ± 3.6 °F]. Specimens should rest
individually on edge, supported by a racking system in the
container and
be in surface-to-surface contact with
each other.
5.2.3
Remove the specimens individually from the water and
lay on a panel of dry polyethylene film, which, in turn, is laid on
a flat surface. Using an elastomeric roller, roll the surface of
the specimen three or four times in one direction until the sur-
face is free of water. Turn the specimen over on a dry area of
the polyethylene film and repeat the preceding step. Place the
3000 Lakeside Drive, Suite 309S
Bannockburn, IL 60015-1249
IPC-TM-650
TEST METHODS MANUAL
Number
2.6.2
Subject
Moisture Absorption, Flexible Printed Wiring
Date
2/12
Revision
D
Originating Task Group
Flexible Circuits Test Methods Subcommittee
(D-15)
Association
Connecting
Electronics
Industries
shall
not
Material
/n
this
Test
Methods
Manual
was
voluntarily
established
by
Technical
Committees
of
I
PC.
This
material
/s
advisory
only
and
"s
use
or
adaptation
，
s
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
/s
for
the
convenience
of
the
user
and
does
not
imply
endorsement
by
IPC.
Page
1
of
2
specimen between layers of absorbent paper and roll three or
four times. Repeat until there is no apparent absorption by the
paper. Place immediately into the tared weighing bottle, cover
the bottle, weigh and record to the nearest 0.001 gram.
NOTE:
This is the most critical part of the test. Care must be
given to removing moisture from the specimens. Limit time
between removal from water to putting in weighing bottle to
≤30 seconds.
5.3 Evaluation
Calculate the water absorption for each
specimen as follows:
Percent of Absorption =
W
2
− W
1
W
1
x 100
where:
W
1
= weight before immersion (see 5.2.1)
W
2
= weight after immersion (see 5.2.3)
Average the results of the three specimens and report this
average to nearest 0.1%.
NOTE:
If the range of results for the three individual speci-
mens exceeds1%, the test must and
be repeated.
Number
2.6.2
Subject
Moisture Absorption, Flexible Printed Wiring
Date
2/12
Revision
D
IPC-TM-650
shall
Page
2
of
2
Figure 4 Tolerances for Terminal-Peak Sawtooth Shock Pulse
Figure 5 Tolerance Limits for Measuring System Frequency Response
IPC-TM-650
Page 5 of 5
SYSTEM
INCLUDING
TRANSDUCER
Number
3.8
Subject
Mechanical
Shock,
Connectors
Date
7/75
Revision
A
IPC-3-8-4
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FREQUENCY
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IPC-3-8-5