Issue 15

P. F. Fuchs et drops of al mber of drop

alii, Frattura ed l PCB build s until failure

Integrità Struttu -ups in the B of the BLD

rale, 15 (2011) LDT. This T.

64-73; DOI: 10 factor was u

.3221/IGF-ESIS.

15.07

BL fict

CBT through itious times-t

the averag o-failure bas

e number of ed on the nu

sed to calcu

late

R E

D ISCUSSIO

SULTS AND

N

T

he resul average perform forcement in lt with glass s used for the ct, regarding nounced, ap sion of desig

ts of the perf of nine m ances for the the surface fibre reinfor IL3 layers, the reinfor parently due n 1, resulting

ormed BLDT easurements six tested bu layers. While ced IL3 layer resulting in a cement of th to the differ in a BLDT p

are present respectively ild-ups. The design 1, ha s, performed worse BLDT e IL3 layers ent material erformance

ed in Fig. 8 i . The resul large gap be ving unreinf worst of all performanc , could be o manufacture in the range o

n terms of d ts show the tween design orced outer l designs. In e compared bserved as s. Design 6 f design 3.

rops until fai desired w s 1 and 2 res ayers (IL3), p design 3 a di to design 1. for designs 1 was a low d

lure. The pill ide range o ults from the erformed ve fferent neat For designs 4 and 2. The ielectric cons

ars represent f board BL influence of ry well, desig epoxy resin and 5 the s effect was tant epoxy r

the DT the n 2, type ame less esin

rein bui wa effe pro ver

Fig

ure 8 : Results

of the BLDT

performed on

six PCB desig

ns. Additiona

l to the averag

e values the st

andard deviati

ons are indicat

ed.

Figure 9 : B

LCBT results

showing the am the standar performed o ented in Fig ude, resulted tested design tter, the faste et-up 1 to b LCBT result

plitude depe d deviations a n three speci . 9 in terms in significant s were very r set-up 1 wa e able to per s of set-up 1

ndence. Addit re indicated. mens for eve of cycles unt longer times similar for s chosen for form a statis . The numbe

ional to the av

erage values

BL Set app per adv Fiv BL

CBT with tw -Up 1 and B lication of th centage, the antage regar e more spec DT results w

o different s LCBT Set-U e lower defle differences ding the mea imens were ere compare

et-ups were p 2 are pres ction amplit between the surement sca tested with s d with the B

ry design. T il failure. As until failure the set-ups. further tests tic evaluatio r of cycles un

he average re expected, se . Nevertheles As set-up 2 . n of the dat til failure in

sults of BLC t-up 2, with s, if expresse did not have a. In Fig. 10 the BLCBT

BT the d in an the was

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