IPC-TM-650 EN 2022 试验方法.pdf - 第697页

5.2.4 Repeat the above cycle to 100 cycles without interrup- tion. 5.2.5 Remove the specimens and allow them to reach labo- ratory conditions as specified in IPC-SM-840. 5.2.6 Evaluation Examine the specimens, on both si…

Scope

This

test method is to determine the physical

endurance of applied polymer solder mask to sudden

changes of high and low temperature excursions to cause

physical fatigue.

Applicable Documents

IPC-CC-830

Qualification

and Performance of Electrical

Insulating Compounds for Printed Board Assemblies

IPC-SM-840

Qualification

and Performance of Permanent

Coating (Solder Mask) for Printed Boards

Test Specimens

3.1 Qualification Testing

Six

IPC-B-25A test boards (see

Figure 1) coated with solder mask and cured in accordance

with solder mask supplier’s recommendations.

3.2

Conformance Testing

Six

IPC-B-25A boards (see Fig-

ure 1) containing the C pattern (‘‘Y’’ pattern) with 0.635 mm

lines/0.635 mm spacing [25.00 mil lines/25.00 mil spacing] or

minimum spacing on the production board, whichever is

smaller, coated with solder mask according to the coating

supplier’s recommendations.

Apparatus

4.1 Chamber

Automatically

controlled dual temperature

environmental test equipment or two separate chambers

capable of maintaining -65° ± 5°C [-85° ± 9°F] and +125° ±

5°C [+257° ± 9°F].

Procedure

5.1 Specimen Preparation

order to test the compatibil-

ity of solder mask with conformal coating, conformal coat

three of the above test specimens with a coating in accor-

dance with IPC-CC-830 and cure in accordance with the

coating supplier’s recommendations

5.2

Test

5.2.1

Place

the test specimens into the test chamber, so that

they do not touch one another, and set the parameters as fol-

lows:

a. Temperature Extremes: as specified in IPC-SM-840 ± 5°C

[± 9°F].

b. Dwell Time at Temperature Extremes: 15 minutes

c. Transfer Time: Less than two minutes

d. Number of Cycles: 100

5.2.2

Activate

the test chamber and begin testing.

5.2.3

One

thermal cycle consists of the following:

a. Expose the specimens to the high temperature for 15 min-

utes.

b. Transfer the specimens to the low temperature in less than

two minutes.

c. Expose the specimens to the low temperature for 15 min-

utes.

d. Transfer the specimens to the high temperature in less

than two minutes.

IPC-2673-1

Figure

1 IPC-B-25A Test Board

2215

Sanders Road

Northbrook, IL 60062-6135

IPC-TM-650

TEST

METHODS MANUAL

Number

2.6.7.3

(Supersedes

2.6.7.1 for Solder Mask Test)

Subject

Thermal Shock - Solder Mask

Date

07/00

Revision

Originating Task Group

Solder Mask Performance Task Group (5-33b)

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.

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5.2.4

Repeat

the above cycle to 100 cycles without interrup-

tion.

5.2.5

Remove the specimens and allow them to reach labo-

ratory conditions as specified in IPC-SM-840.

5.2.6

Evaluation

Examine the specimens, on both sides,

for all visual requirements of IPC-SM-840 using 10X magnifi-

cations (Referee of 30X magnifications).

Note: The presence of cracks in solder mask is not a suffi-

cient reason for rejection unless the conformal coating has

also cracked. Report findings and support results with the

photographs, if appropriate.

IPC-TM-650

Number

2.6.7.3

Subject

Thermal

Shock - Solder Mask

Date

07/00

Revision

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Scope

This

test is performed for the purpose of determin-

ing whether plated-through holes can withstand the thermo-

dynamic effects of the extreme heat to which they may be

exposed during the assembly, rework, or repair process.

Applicable Documents

J-STD-001

Requirements

for Soldered Electrical and Elec-

tronic Assemblies

J-STD-004

Requirements

for Soldering Fluxes

IPC-2221

Generic

standard on Printed Board Design

IPC-TM-650

Test Methods Manual

2.1.1

Microsectioning

2.1.1.2 Microsectioning – Semi or Automatic Technique

Microsection Equipment (Alternate)

Test Specimen

3.1

The

test specimen shall be a printed board, a portion of

a printed board or a test coupon as described in IPC-2221,

which allows for microsection evaluation of both the largest

component holes and the smallest holes on the board.

3.2

The

test specimen shall be removed from a printed

board or test coupon as specified in IPC-TM-650, Method

2.1.1 or Method 2.1.1.2, prior to precondition bake.

Apparatus or Material

4.1

Drying

oven capable of maintaining a uniform tempera-

ture between 121C to 149 °C [250 °F to 300 °F].

4.2

Solder

pot, electrically heated, thermostatically con-

trolled, of sufficient size, containing at least 0.9 kg of

Sn60Pb40 or Sn63Pb37 solder conforming to the contami-

nant level specified in J-STD-001.

4.3

Thermocouple

indicator or other devices to measure the

solder temperature 19 mm ± 6.4 mm [0.748 in ± 0.252 in]

below the surface.

4.4

Desiccator

with suitable desiccant.

4.5 Microscope

(100X to 200X magnification).

4.6

Stop

Watch or Timer.

4.7

Rosin

Flux, type ROL1 per J-STD-004, or flux agreed

upon between customer and vender.

4.8

Tongs.

4.9

Suitable

solvent for flux removal following the thermal

stress such as isopropyl alcohol.

Procedure

5.1

The

test specimen shall be conditioned by drying in an

oven for an appropriate period at 121 °C to 149 °C [250 °F to

300 °F] to remove the moisture in the specimen. For referee

purposes, a dry for a minimum of six hours at 121 °C to

149 °C [250 °F to 300 °F] shall be used. Thicker or more com-

plex specimens may require longer baking times.

5.2

Place

the test specimen in a desiccator on a ceramic

plate to cool to room temperature.

5.3

Remove

the test specimen from the desiccator using

tongs. Flux coat the surface and plated-through holes to

insure solder filling.

5.4

Verify

that the temperature of the solder (at a probe

depth of 19 mm ± 6.4 mm [0.748 in ± 0.252 in] from the sur-

face of the solder) is maintained at one of the following speci-

fied test conditions (see 6.1):

(a)

Test Condition A (default)

288

°C ± 5 °C [550 °F ± 9 °F]

(b)

Test Condition B

260

°C ± 5 °C [500 ° ± 9 °F]

(c)

Test Condition C

232

°C ± 5 °C [450 °F ± 9 °F]

5.5

Remove

the dross from the solder pot surface and lay

the test specimen on the solder for 10 seconds +1, -0 sec-

onds (see 6.2).

5.6 Using

tongs, carefully remove the test specimen from

the solder and place it on a piece of insulator to cool to room

temperature (see 6.3).

5.7

Evaluation

2215

Sanders Road

Northbrook, IL 60062-6135

IPC-TM-650

TEST

METHODS MANUAL

Number

2.6.8

Subject

Thermal

Stress, Plated-Through Holes

Date

05/04

Revision

Originating Task Group

Rigid Printed Board Performance Task Group

(D-33a)

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.

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TION CONNECTING

ELECTRONICS INDUSTRIES

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