IPC-TM-650 EN 2022 试验方法.pdf - 第737页

3.6.2 Report the results of the visual examination evaluation in 3.4.9. 4 Dielectric Strength Using ASTM D-149 Test Procedure 4.1 Specimen Preparation 4.1.1 Prepare a specimen of the metal-clad flexible base material lar…

3.4.2 Measure the flexible base dielectric thickness and the

metal thickness of the twelve specimens by micrometer, cali-

per or similar following the stabilization period in 3.4.1. Nomi-

nal metal thickness to be tested is either 1 oz or 34.3 µm

[1350 µin] thick (preferred) or

⁄

oz or 17.1 µm [680 µin] thick.

3.4.3 On the specimens stabilized in 3.4.1, measure and

verify that the conductor widths are 3.2 mm ± 0.15 mm

[0.126 in ± 5.9 µin].

3.4.4 Examine the twelve specimens measured in 3.4.3

using normal or corrected 20/20 (also termed 6/6 or 1.0)

vision, and discard any peel strips showing the presence of

any wrinkles, cracks, blisters, or loose conductors. Twelve

specimens are required for the test, so any specimens not

meeting this criterion shall be replaced.

3.4.5 Per IPC-TM-650, TM 2.4.13, Method B, subject the

specimens examined in 3.4.4 to pre-drying and then solder

float.

3.4.6 Examine the specimens subjected to solder float in

3.4.5 using normal or corrected 20/20 (also termed 6/6 or 1.0)

vision. Discard any peel strips showing the presence of any

wrinkles, cracks, blisters, or loose conductors. Verify that at

least twelve good specimens remain.

3.4.7 Place six specimens into an air-circulating oven at the

desired Service Temperature value. The oven temperature

shall be held at a tolerance of ± 3°C [5.4 °F]. The specimens

are to continuously remain in the oven for 1000 hours, -0

hours / +12 hours.

3.4.8 After being aged per 3.4.7, the test specimens shall

be cooled to room temperature at standard ambient labora-

tory conditions. After being cooled to room temperature, the

thermally aged (oven conditioned) specimens shall be sub-

jected to a stabilization period of a minimum of 24 hours at

23 °C ± 2 °C [73.4 °F ± 3.6 °F] and 50% ± 5% RH.

3.4.9 After the stabilization period in 3.4.8, examine the

specimens using normal or corrected 20/20 (also termed 6/6

or 1.0) vision, and record the presence of any wrinkles,

cracks, blisters, or loose conductors, or any delamination.

3.5 Measurement of Peel Strength

3.5.1

AABUS, test specimens may have rigid reinforcement

material attached to all twelve specimens that were subjected

to the solder float in 3.4.5, including those six specimens that

were additionally subjected to thermal aging in 3.4.7. The rigid

reinforcement material shall not be attached prior to condi-

tioning and aging. The attachment of the rigid reinforcement

material depends on a number of factors, including the type of

peel test apparatus as described in IPC-TM-650, Method

2.4.9. If the rigid reinforcement material is to be utilized, it

should be adhered to the specimens using double-faced

adhesive tape or appropriate adhesive system to the back

side of the specimens.

If the test specimens are generated from double-clad flexible

base materials with metal remaining on the non-test side, the

additional rigid reinforcement material is unnecessary and

should not be used.

3.5.2 Measure the peel strength of the twelve conductors

per the procedures outlined in IPC TM-650, Method 2.4.9.

Specifically, peel the etched copper conductors away from

the dielectric at a 90° angle and at a 50.8 mm [2 in] per min-

ute crosshead speed.

3.6 Document and Report Results

3.6.1

Calculate the average peel strength of the six speci-

mens that were only exposed to the solder float (i.e., only as

per 3.4.5 and not exposed to the thermal aging of 3.4.7). Do

the same for the six thermally aged specimens per 3.4.7. Cal-

culate the ratio of the ‘‘thermally aged’’ average peel

strengths divided by the solder-floated only average peel

strength to determine the percentage retention of peel

strength. Record this number to ± 1% accuracy.

[Ave. of Six (6) Peel Strengths of Thermally Aged Specimens]

[Ave. of Six (6) Peel Strengths of Solder Floated-Only Specimens

x100=%ofPeel Strength Retained

IPC-2-6-21-2

Figure 2 Use of Adhesive Bonding Film to Form Test

Specimen

1 oz ED or RA Copper Foil Test Surface

(Shiny side toward the adhesive)

1 oz ED Copper Foil with Treated Matte

Side Inward as Support Material

Adhesive Bonding Film

IPC-TM-650

Number

2.6.21

Subject

Service Temperature of Metal-Clad Flexible Laminate, Cover

Material and Adhesive Bonding Films

Date

6/11

Revision

Page3of5

3.6.2 Report the results of the visual examination evaluation

in 3.4.9.

Dielectric Strength Using ASTM D-149 Test Procedure

4.1 Specimen Preparation

4.1.1

Prepare a specimen of the metal-clad flexible base

material large enough [approximately 400 mm x 500 mm

[approx. 16 in x 20 in]] to prepare at least twelve test speci-

mens each of 80 mm x 80 mm [approx. 3.0 in x 3.0 in]. Cover

materials shall be prepared per 3.2. Adhesive bonding films

shall be prepared per 3.3 where copper foil is used on both

sides of the adhesive bonding film.

4.1.2 Remove (etch) all metal from both surfaces of the

400 mm x 500 mm [approx. 16 in x 20 in] specimen by stan-

dard industry practice. Rinse the etched material thoroughly.

Cut the minimum of twelve test specimens to their nominal

size of 80 mm x 80 mm [approx. 3.0 in x 3.0 in].

4.2 Conditioning and Aging Procedure

4.2.1

After generating the minimum of twelve specimens as

described in 4.1.1, all specimens shall be subjected to a sta-

bilization period of a minimum of 24 hours at 23 °C±2°C

[73.4 °F ± 3.6 °F] and 50% RH ± 5% RH.

4.2.2 Examine at least twelve specimens using normal or

corrected 20/20 (also termed 6/6 or 1.0) vision, and record

any presence of any wrinkles, cracks or blisters. Discard those

specimens showing the presence of any wrinkles, cracks or

blisters.

4.2.3 Six specimens examined in 4.2.2 shall be placed into

an air-circulating oven at the desired Service Temperature

value. The oven temperature shall be held at a tolerance of ±

3 °C [± 5.4 °F]. The specimens are to continuously remain in

the oven for 1000 hours, -0 hours / +12 hours.

4.2.4 After being oven-conditioned as described in 4.2.3,

the test specimens shall be cooled to room temperature at

standard ambient laboratory conditions. After being cooled to

room temperature, the oven-conditioned specimens shall be

subjected to a stabilization period of a minimum of 24 hours

at 23 °C ± 2° C [73.4 °F ± 3.6 °F] and 50% ± 5% RH.

4.2.5 After the stabilization period in 4.2.4, examine the six

specimens that had been subjected to the oven- conditioning

using normal or corrected 20/20 (also termed 6/6 or 1.0)

vision, and record the presence of any wrinkles, cracks or

blisters.

4.3 Measurement of Dielectric Strength

4.3.1

The six specimens that were not subjected to the

oven-conditioning in 4.2.3 shall be subjected to the dielectric

strength test per ASTM D-149. (These measurements shall

be considered the ‘‘as-received’’ dielectric strength values.)

4.3.2 The ‘‘thermally aged’’ (oven-conditioned) specimens

examined in 4.2.5 shall be tested for dielectric strength

according to the conditions outlined in 4.3.1. (These measure-

ments shall be considered the ‘‘thermally-aged’’ dielectric

strength values.)

4.4 Evaluation of Results

4.4.1

Calculate the average dielectric strength of the six

‘‘as-received’’ specimens as measured in 4.3.1. Calculate the

average dielectric strength of the six ‘‘thermally aged’’ speci-

mens as measured in 4.3.2. Calculate the ratio of the average

value of the ‘‘thermally aged’’ dielectric strength divided by

the average value of the ‘‘as-received’’ dielectric strength to

determine the percentage retention of dielectric strength.

Record this number to ± 1% accuracy.

[Ave. of Six (6) Diel. Strengths of ‘‘Thermally Aged’’ Specimens]

[Ave. of Six (6) Diel. Strengths of ‘‘As Received’’ Specimens

x100=%ofDielectric Strength Retained

IPC-TM-650

Number

2.6.21

Subject

Service Temperature of Metal-Clad Flexible Laminate, Cover

Material and Adhesive Bonding Films

Date

6/11

Revision

Page4of5

5 Data Reporting

5.1

Report both percent values calculated in sections 3.6.1

and 4.4.1. The Service Temperature value, in units of °C,

shall be based upon the lesser of the two reported percent

values calculated in sections 3.6.1 and 4.4.1.

6 Notes

6.1

For specimen preparation, test results may vary

between specimens where the copper remains and those that

have had the copper removed from the nontest side. If the

flexible base material is supplied as single-clad and double-

clad, both must be tested.

6.2 For specimen preparation, test results may vary for the

same flexible base material, depending whether it is tested as

single- or double-clad.

6.3 Suitable procedures must be used to ensure that solder

does not remain on the test specimens after solder float.

6.4 For flexible base materials other than polyimide, the tem-

perature of the solder pot may be other than 288 °C [550 °F],

AABUS.

IPC-TM-650

Number

2.6.21

Subject

Service Temperature of Metal-Clad Flexible Laminate, Cover

Material and Adhesive Bonding Films

Date

6/11

Revision

Page5of5