Issue 62

Y. S. Rao et alii, Frattura ed Integrità Strutturale, 62 (2022) 240-260; DOI: 10.3221/IGF-ESIS.62.17

The toughness of each composite specimen K IC as per ASTM D5045 according to pure mode-I loading is estimated using Eqn. (1) [54]. The factor f(a/W) in Eqn. (1) was computed by Eqn. (2) [55,56]. The K I and K II are the stress intensity components determined as per ASTM E1820 according to the mixed-mode I/II loading by Eqn.s (3) and (4) [55,57]. The values of normalized geometric function F I and F II are 0.3193 and 0.0715 respectively for the present case is estimated by interpolation based on the value found in the literature [57,58]. The bending stress in Eqns. (3) and (4) was computed by Eqn. (5).

max 3/2 P S a BW W

     

(1)

K = .f

IC

   

   

   

   

1/2

2

      a W

      a

a

      a

      a

  

3

1.99-

1-

2.15-3.93 +2.7

W W

W W

      f a = W

(2)

3/2

2a

a

  

  

  

2 1+ 1

W W

I 0 I K = σ F Π a

(3)

II 0 II K = σ F Π a

(4)

2 3PS 2W B

(5)

0 σ =

Sl.no.

hBN

MoS 2

1/D (nm -1 )

d-spacing (nm)

h k l

1/D (nm -1 )

d-spacing (nm)

h k l

1

5.90

0.34

(0 0 2)

7.41

0.27

(1 0 1)

2

9.01

0.22

(1 0 0)

8.80

0.23

(0 1 2)

3

9.73

0.21

(1 0 1)

12.68

0.16

(0 1 5)

4

11.18

0.18

(1 0 2)

13.07

0.15

(0 0 9)

5

14.90

0.13

(1 0 4)

14.83

0.13

(1 0 7)

6

16.04

0.12

(1 1 0)

15.95

0.12

(1 1 0)

7

17.04 - Table 3: The interplanar spacing of hBN and MoS 2 based on the SAED pattern. 0.11 (1 1 2) - -

R ESULTS AND DISCUSSION

Morphology of fillers he hBN-ethanol and MoS 2 -ethanol homogenously dispersed solution was prepared, and a drop was taken on a carbon-coated copper grid and morphology was studied by the HRTEM. The HRTEM images at various magnifications of hBN and MoS 2 fillers are shown in Fig. 2. It is found that most of the hBN resembles 2D disk and (Fig. 2(a-b)) few of flake type (Fig. 2(c)). The hBN size is between 52-201 nm (Fig. 2(b)) and spacing between the layers is 0.34 nm corresponds to the (002) lattice plane (Fig. 2(d)). The HRTEM images of MoS 2 filler shown in Fig. 2(f-i). It T

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