Issue 61

E. Ashoka et alii, Frattura ed Integrità Strutturale, 61 (2022) 473-486; DOI: 10.3221/IGF-ESIS.61.31

6

A l 6 0 6 1 - 3 W t% S i C - 9 W t% C e n o s p h e r e B /W = 0 . 5

a /W = 0 . 3 a /W = 0 . 4 a /W = 0 . 5 a /W = 0 . 6

5

4

3

2

Load,kN

1

0

0

1

2

3

4

5

D i s p l a c e m e n t ,m m

Figure 7: Load vs. CMOD curves for Al6061+3wt% SiC+ 9wt% Cenosphere. Figs. 5 to 7 reveals that the load carrying capacity of the said hybrid composite decreases with increase in a/W ratios for all the compositions. For the said Al6061-SiC/Cenosphere composites and a/W ratios, the provisional fracture toughness K Q has been determined using the empirical equations [37-40] by considering the values of critical load (P Q ) and dimensions of CT specimens.

13.0 13.2 13.4 13.6 13.8 14.0 14.2 14.4 14.6 14.8 15.0

Al6061-3wt% SiC-3wt% Cenosphere Al6061-3wt% SiC-6wt% Cenosphere Al6061-3wt% SiC-9wt% Cenosphere

Fracture Toughness MPam 1/2

0.30

0.35

0.40

0.45

0.50

0.55

0.60

a/W

Figure 8: Variation of fracture toughness vs. a/W ratio . Fig.8 shows the fracture toughness of Al6061-SiC/Cenosphere hybrid composite with increasing a/W ratio. From the Fig.8 it is observed that increment in the crack length to width ratio reduces the fracture toughness of the Al6061-

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