Issue 15

K. V

ogel et alii, Fra

ttura ed Integrit

à Strutturale, 15

(2011) 21-28;

DOI: 10.3221/IG

F-ESIS.15.03

placement u z tive crack len a w  

ces F are sim

dis rela

constant, the gths

reaction for

ulated subje

cted to a wel

l defined cra

ck propagati

on. For diffe

rent

a

a

0

1

0  

1  

(2)

w

w

C(  ) can be i

the

using the equ

compliance

nterpolated,

ation

( ) z u F 

( ) C  

(3)

ratio  of sili

kness t of the

dulus E and

the Poissons

Aft [10

er scaling the ]

compliance

sample, the

Young’s mo

con

with the thic

( 1 ² E t C      the stress inte )

'( ) C  

(4)

function of

nsity coeffic

ient can be d

etermined

the

d C

1 0 0 '( )        

1 2

( ) Y  





(5)

d 

cient Y MIN

g Y MIN

Eq. (1) leads

Its tou

minimum, t ghness.

he stress int

ensity coeffi

c

an be calcula

ted. Insertin

in

to the frac

ture

E X hou and I the pre

PERIMENT

n addition micro-chev divided int particle conc -bonded at r rs. The anne the bottom

to the numer ron-test. Bef o the followi entration ha oom tempera aling conditi of the specim

ical determin ore carrying ng steps. Fir s to be reduc ture afterwar ons can vary en, Fig. 3. B

ation of the out the expe st, all Si wafe ed within a s ds. Before di between dif efore starting

stress intensi riments, the rs are RCA-c pin dryer, aft cing the wafe ferent batche the experim

ty coefficient samples have leaned befor er rinsing the r stacks into s. To initiate ent, the spec

m force is m red. Their pr e low pressu ionised wate hey have to b o studs are e preloaded

easured durin eparation can re plasma. T r. The wafers e annealed f glued on the .

the maximu to be prepa e applying th wafers in de specimens, t the force, tw imen has to b

g a be hen are or 6 top

Figu

re 3 : Preparati

on of the micr

o-chevron-sam

ples.

24