IPC-TM-650 EN 2022 试验方法-- - 第402页

Figure 15 T est Fixture Construction, Older Design IPC-TM-650 Page 23 o f 25 r 50.11 Q ] 0 0 r Dim ”B” — 76.76 - 73.58 - 72.67 69.49 - 66.32 - 17.75 14.58 6.65 3.48 3.05 hole, 2 places Drill & tap for #4-40 screw, 4 …

Users of this test method should apply the principles outlined

in E-691 to generate the data specific to their laboratory and

materials, or between specific laboratories. The principles

would then be valid for such data.

7.4.2

Concept of r and R (Reference ASTM D5045, Section

11.2). If Sr and SR have been calculated from a large enough

body of data, and for test results that were averages from

testing three specimens, the following information applies.

7.4.2.1

Repeatability, r (comparing two test results for the

same material, obtained by the same operator using the same

equipment on the same day). The two test results should be

judged not equivalent if they differ by more than the r value for

that material.

7.4.2.2

Reproducibility, R (comparing two test results for the

same material, obtained by different operators using different

equipment on the same day). The two test results should be

judged not equivalent if they differ by more than the R value

for that material.

7.4.2.3

Any judgement in accordance with the above would

have an approximate 95 % (0.95) probability of being correct.

7.4.3 Bias

There are no recognized standards by which to

estimate bias of these test methods.

7.4.4 Keywords (Reference ASTM D 5045, Section 12)

• Critical-strain energy release rate

• Energy-to-break

• Fracture toughness

• Plane-strain fracture toughness

References

(1) Brown, W. F., Jr., and Srawley, J. E., “Plane Strain Crack

Toughness Testing of High Strength Metallic Materials,” ASTM

STP 410, ASTM, 1966, p.1.

(2) “Fracture Toughness Testing and Its Applications,” ASTM

STP 381, ASTM, April 1965, p.30.

(3) Srawley, J. E., “Wide Range Stress Intensity Factor

Expressions for ASTM E399 Standard Fracture Toughness

Specimens,” International Journal of Fracture Mechanics, Vol.

12, June 1976, p.475.

(4) Newman, J. C., “Stress Analysis of Compact Specimens

Including the Effects of Pin Loading,” ASTM STP 560, ASTM,

1974, p.105.

(5) Williams, J. G., “Fracture Mechanics of Polymers,” Ellis

Horwood/Wiley, 1985.

(6) Towers, O. L., “Stress Intensity Factors, Compliances and

Elastic η

Factors for Six Test Geometries,” The Welding Insti-

tute, March 1981.

Number

2.4.52

Subject

Fracture Toughness of Resin Systems for Base Materials

Date

07/13

Revision

Page 8 of 8

IPC-TM-650

Figure 15 Test Fixture Construction, Older Design

IPC-TM-650

Page 23 of 25

50.11

]

Dim

”B”

—

76.76

73.58

72.67

69.49

66.32

17.75

14.58

6.65

3.48

3.05

hole,

places

Drill

tap

for

#4-40

screw,

places

Drill

tap

for

#1-72

screw,

places

17.75

v—

14.58

!■*—

6.65

•-

548

—

1.40

—

6.35

DETAIL

aluminum

one

req'd

26.64—

10.44

—

7.26

——

—

4.09

—

3.17

—

Nate:

Specimen

nominal

thickness

1.27

1.57

Dimension

"A"

for

base

plate

4.78

5.08

Dimension

"A"

for

base

plate

4.47

4.78

K3F

mrn

17.75

14.58

17.75

14.58

6.65

3.48

3.05

hole,

places

DETAIL

aluminum

one

req'd

Drill

3.05

countersink

for

screw,

places

Drill

2.06

countersink

for

screw,

places

—

76.76

一

73.58

72.67

69.49

66.32

—

50.11

26.64

10.44

7.26

——

4.09

—

3.17

6.65

3.48

二

及

=K5F

册

1.40

6.35

PC-2555-15

Number

2.5.5.5

Subject

Stripline

Test

for

Permittivity

and

Loss

Tangent

(Dielectric

Constant

and

Dissipation

Factor)

X-Band

Date

3/98

Revision

r-TTHn

29.0

996L

R7Z

5.3.2

If there is a metal heat spreader on the BGA, it must

be left in place until after the dye-drying step (5.11).

5.4

Section out the desired component area leaving about

19 mm to 38 mm [0.75 in to 1.5 in] of board around the part.

If the board is small enough to fit the pull fixture, leave the

board intact.

5.4.1

A diamond sectioning saw is recommended to per-

form this step. Other sectioning equipment (e.g., diamond

saw, milling tool, water jet, etc.) can be used if it does not

induce stress on the sample area.

5.5

A detailed visual examination under stereomicroscope is

required at this stage. If needed, clean the sectioned part with

only water and compressed air. It is important to not use sol-

vent for this step.

5.5.1

A thorough visual examination can detect signs of

mechanical damage/stress, which are indicated by fractured/

broken-up flux around the SMT solder joint (see Figure 1 and

Figure 2).

5.5.2

If the SMT part utilizes corner-applied adhesive which

was not easily visible before, examine it now. Document the

glue coverage per IPC-7095 or as determined between the

lab and the customer.

5.5.3

Document the findings in lab notes and with photos.

5.6

Clean any flux residue from around the SMT solder joints

using the appropriate flux remover.

Isopropyl alcohol is not acceptable due to its inability to

dissolve flux.

5.6.1

The sectioned part/board area should be submerged

in liquid flux remover for at least one hour. The goal is to fully

remove the flux residue. The exact amount of time the part/

board is submerged depends on the sample conditions.

5.6.1.1

Approximately two to three times during soak, gen-

tly swirl the beaker containing the sectioned part for at least

20 seconds. This will aid the flux solvent in removing the flux

ring residue.

5.6.2

Reworked samples may require additional time in the

liquid flux remover.

5.6.3

Examine the sample under a microscope to determine

if additional time is needed to remove the flux ring.

5.6.4

After using the liquid flux remover, use a spray can flux

remover to thoroughly flush all four sides of the component.

5.6.4.1

Removing all flux residues and other particles/oils

enables the dye to penetrate the fractures.

5.6.4.2

Failure to completely remove the flux from around

the solder joint will prevent dye penetration and give false indi-

cations of a good solder joint.

5.7

Use low-pressure compressed air to blow off excess flux

solvent.

5.7.1

If desired, perform a final rinse with isopropyl alcohol

or acetone at this time.

5.8

Pour the dye into a small tray until the sectioned sample

is completely immersed in the dye.

5.8.1

If dye is being reused, ensure it has sufficient viscos-

ity. Viscosity is critical to the ability of the dye to penetrate into

cracks within the parts being dyed. If there are any concerns

with dye viscosity, discard the old dye and use fresh, new

dye.

5.9

Place the tray containing the sectioned sample into a

vacuum chamber.

5.9.1

Draw a 67.7 kPa [20 in Hg] vacuum for three to four

minutes.

5.9.2

Partially vent and then reapply vacuum to the chamber

to aid in dye penetration.

5.9.3

Leave the part submerged in dye for a minimum of 30

minutes with a constant vacuum of 67.7 kPa [20 in Hg].

5.9.3.1

Do not exceed 67.7 kPa [20 in Hg] of vacuum at any

time, or the dye will start to boil off.

5.10

Vent the vacuum chamber slowly and remove the

sample from the tray.

5.10.1

Allow the excess dye to drain off the sample.

Number

2.4.53

Subject

Dye and Pull Test Method (Formerly Known as Dye and Pry)

Date

8/2017

Revision

Page 2 of 11

IPC-TM-650

Note: