IPC-TM-650 EN 2022 试验方法.pdf - 第229页

Note: For flexural fatigue tests lasting in excess of 1000 cycles, the adhesive tape attachment needs to be substantial enough to prevent relative sliding of specimen and sample holder as a result of the cyclic flexure m…

Scope

Ductility

values are determined by measuring the

bulge height on a Mullen bulge tester or equivalent. Measure-

ments are made in mm.

Applicable Documents

None

Test Specimen

Three

clean, smooth pieces of copper

foil 10 cm x 10 cm area or any non-overlapping equivalent

areas.

Apparatus

Mullens

Bulge Tester by B. F. Perkins & Son,

Inc., Model A to be 10 RPM at large shaft between gear box

and diaphragm, or equivalent.

Procedure

5.1 Preparation

Raise

upper clamping ring by rotating the

hand wheel. Place a 10 cm x 10 cm by 0.15 mm thick steel

plate that is perfectly flat over the diaphragm and lower the

upper clamping ring applying sufficient pressure to prevent

slippage. Zero the dial indicator. Raise the upper clamping

ring and remove the 10 cm x 10 cm by 0.15 mm steel plate.

NOTE:

The

above operation should be done once every

eight-hour shift.

Start the motor and move the ball-handled control lever to the

right to be certain that the diaphragm is returned to its start-

ing position.

5.2

Test

5.2.1

Place a sample of the copper foil to be tested over the

diaphragm with the matte side up.

5.2.2

Lower

the clamping ring, applying sufficient pressure

to prevent slippage of the sample between the plates.

5.2.3 Move

the ball-handled control lever to the left. The

operator should keep his hand on the lever in readiness to

stop or reverse the machine at any time during the test and

when the test is complete. During the test, the operator

should be watching the dial indicator and, at the instant burst-

ing occurs, should note the reading on the dial indicator and

the ball-handled control lever should be moved as far to the

right as it will go and be released. This will return the dia-

phragm to its starting position and automatically shut off the

pump.

5.3

Evaluation

5.3.1

Record

the reading from the dial indicator.

5.3.2

Rotate

the hand wheel to raise the clamping ring and

remove the sample. Avoid overlapping of the clamping areas

and disregard any single reading that is not reasonably con-

sistent with those taken in neighboring areas, and repeat the

test.

The

Institute for Interconnecting and Packaging Electronic Circuits

2215 Sanders Road • Northbrook, IL 60062-6135

IPC-TM-650

TEST

METHODS MANUAL

Number

2.4.2

Subject

Ductility

of Copper Foil

Date

3/76

Revision

Originating Task Group

N/A

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.

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Note:

For

flexural fatigue tests lasting in excess of 1000

cycles, the adhesive tape attachment needs to be substantial

enough to prevent relative sliding of specimen and sample

holder as a result of the cyclic flexure movements.

5.2

Test Procedure

5.2.1

Mount

mandrels to flex tester, adjust the support

roller positions for a clearance of 1.27 mm [0.05 inch] (shim

provided) between rollers and mandrels.

Note:

For

the ductility test, it is important that the specimens

fail between 30 and 500 cycles. Mandrels with 2.0 or 1.0 mm

[0.079 or 0.040 inch] diameter are suggested but for some

samples, mandrel diameters different from these diameters

might be necessary. Larger mandrel diameters result in longer

cyclic life and smaller diameters in shorter life.

5.2.2

Mount

test specimen between mandrels, attach relay

leads with alligator clips to foil weight wing nut to form ‘‘slip-

off’’ electrical connections, plug relay leads into relay jacks,

set counter to zero, and start flex tester.

5.2.3 Complete

separation of the foil specimen constitutes

failure and the flex tester stops automatically when the drop-

ping foil weight dislodges the alligator clips from the wing nut.

5.2.4

Record

cycles-to-failure indicated on counter.

5.3

Evaluation

5.3.1 Ductility Test

5.3.1.1

Calculate

the ductility for each specimen by itera-

tively solving the formula below:

−0.6

0.75

+ 0.9

[

exp(D

)

0.36

]

(0.1785

log

)

−

21+t

= 0

where:

fatigue ductility, inch/inch (x100,%)

cycles-to-failure

ultimate tensile strength, psi

E = modulus of elasticity, psi

core thickness, inch

t = specimen micrometer thickness, inch

1 = mandrel radius of curvature, inch within 0.005 mm

[0.0002 inch]

Note:

Determine

per Test Method 2.4.18 of IPC-TM-

650. Determine E during the test for S

unloading and

reloading after about 2% elongation and measuring the slope

of the reloading curve.

Note:

The

determination of E foils is not a straightforward

procedure. It is therefore suggested that for specification pur-

poses standard values of E be adopted. For copper foil such

standard values might be: E(CF−E)=12x10

psi

for electro-

deposited foil, E(CF−W)=16x10

psi

for wrought (rolled) foil.

Note:

The

calculator program described in paragraph 6.2

solves the ductility formula and conveniently prompts for all

necessary input parameters.

5.3.1.2

Report

the average ductility from at least three

specimens.

5.3.2

Fatigue Test

The

number of cycles to failure, is the

flexural fatigue life in fully reversed bending for the bend radius

corresponding to the radius (1/2 diameter) of the test man-

drels used. An average flexural life from at least three speci-

mens should be reported.

5.3.3

Fatigue Behavior

The

fatigue behavior of a sample

can be obtained by determining the flexural fatigue life with a

number of different-diameter mandrels. Plotting the results in

a strain range versus fatigue life Manon-Coffin plot log ∆ε =

[2t

/(21 +

t)] versus log N

)

allows intra- and extrapolation to

other bend radii or fatigue lives.

IPC-2421-2

Figure

2 Fatigue ductility ﬂex tester

IPC-TM-650

Number

2.4.2.1

Subject

Flexural

Fatigue and Ductility, Foil

Date

3/91

Revision

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5.3.4

The

flexural fatigue life at bend radii other than man-

drel radius can also be obtained by evaluating the ductility for-

mula for the flex life in cycles-to-failure using the fatigue duc-

tility determined in 5.3.1.2 and the desired bend radius.

6.0 Notes

For

further technical details, reference the mate-

rial shown below.

6.1 Document

in paragraph 2.0 (IPC-TP-204).

6.2 Engelmaier,

W., ‘‘Fatigue Ductility for Foils and Flexible

Printed Wiring,’’ Program No. 1883D HP-67/97 User’s

Library, Hewlett Packard Co., Corvallis, Oregon, 1978.

6.3

Engelmaier,

W., ‘‘Fatigue Ductility Flex Tester,’’ Drawing

L520163, Bell Telephone Laboratories, Inc., Whippany, New

Jersey, 1978.

6.4

Test Equipment Sources

The

equipment sources

described below represent those currently known to the

industry. Users of this test method are urged to submit addi-

tional source names as they become available, so that this list

can be kept as current as possible.

6.4.1

Fatigue

Ductility Flex Tester, Universal Tool & Machine

Inc., 171 Coit St., Irvington, NJ 07111; 201-374-4400.

6.4.2

JDC

Precision Sample Cutter, Model JDC 125-N or

equal.

IPC-TM-650

Number

2.4.2.1

Subject

Flexural

Fatigue and Ductility, Foil

Date

3/91

Revision

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