Issue 14

M.

Merlin, Frattura

ed Integrità Str

utturale, 14 (20

10) 64-74; DOI

: 10.3221/IGF-ES

IS.14.07

Si 0.181 0.179 0.825 Table 1 : ds have been 1. As it can ar has a sphe spot that g order to ha specific thick ility is the le fails or becom

Fe 0.121 0.120 0.115 Average chem manufactur be noted, th rical riser (fe enerates high ve the same ness accordi ngth of the b es seriously

Cu

M

n

Mg

Cr <0.01 <0.01 <0.01 the alloys stud ture-Edward four bars o determines a the contra ar is constra itself. A use cy of the allo

Ni T <0.003 0.1 <0.003 0.2 <0.003 0.2 ied in the pres s design and f different le n abrupt sect ction of the ined at the e ful paramete y to generate

i

Zn

Al bal. bal. bal.

Alloy A Alloy B Alloy C

4.22

0.4

6

<0.01

91

0.07

6.33

0.4

6 <0.01 5 <0.01 ons (wt.%) of g to the Cou composed of side, which esses due to metal, each b th of the bar r the tenden

21

0.069

5.95 0.4 ical compositi ed accordin e casting is eder) on one tensile str quantity of ng to the leng ar; the greate damaged.

24

0.069

ent work.

Th dep pou of sol des tea tha

e sand moul icted in Fig. ring. Each b a local hot idification. In igned with a ring susceptib t completely

the wood ngths produc ion change w alloy along nd by a flan r for the eval hot tears, th

models used ed in one si ith the prese the bar du ge that has b uation of the e shorter the

are ngle nce ring een hot bar

Figure 1 : W nalysis of the ion and coo ly and by a liq der. For exa in the same f

ood model of castings ling, the cas uid penetran mple, a phot igure.

the casting rea

lised to evalua

te the hot tear

ing behaviour

of the alloys.

No Aft ins the is a

n-destructive a er solidificat pected visual spherical fee lso depicted

tings were e t test. Attent o of one cast

xtracted from ion has been ing has been

the sand paid to the m reported in F

moulds; the ost critical z ig. 2; a zoom

cracks on a one, that is t of a compl

ll the bars w he hot spot n etely cracked

ere ear bar

Figure 2

: Photo of a c

asting produce

d in Alloy B w

ith a pouring

temperature o

f 760°C.

66