Issue 62

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

epoxy composite may be required. Design of experiment and finite element analysis is required for further to optimize the filler concentration for better specific structural properties.

N OMENCLATURE

a

initial crack length (mm) pre-exponential term specimen thickness (mm) activation energy (J.mol -1 )

A B

E a

dimensionless correction factor related to specimen geometry and flaw size

f(a/W)

normalized geometric function corresponding to mode-I normalized geometric function corresponding to mode-II critical mode-I stress intensity factor (MPa.mm 1/2 ) mode-I component of stress intensity factor (MPa.mm 1/2 ) mode-II component of stress intensity factor (MPa.mm 1/2 )

F I

F II

K IC

K I

K II

applied load (N)

P R

gas constant=8.314 J.mol -1 K -1

span length between the supports (mm)

S

temperature (°K)

T

specimen width (mm)

W

initial sample weight (grams)

W o W t W f

residual sample weight at any temperature “T” (grams)

final sample weight (grams)

Greek letters σ 0

bending stress (MPa)

degree of decomposition=(Wo-Wt)/( Wo-Wf)

α β

heating rate (°C.min -1 )

C ONFLICT OF INTEREST

he authors have no conflicts of interest. [1] Oladele, I.O., Omotosho, T.F., Adediran, A.A. (2020). Polymer-based composites: An indispensable material for present and future applications, International Journal of Polymer Science, 2020, pp. 1–12. DOI: 10.1155/2020/8834518. [2] Palmer, R.J. (2012). History of composites in aeronautics., Wiley Encyclopedia of Composites, 1st ed., Hoboken, USA, John Wiley & Sons, Inc., pp. 1–40. [3] Lee, T.H. (2012). Review of the composite materials application to the solid rocket motor cases, Journal of the Korean Society for Composite Materials, 25(3), pp. 82–89. DOI: 10.7234/kscm.2012.25.3.082. [4] Rubino, F., Nisticò, A., Tucci, F., Carlone, P. (2020). Marine application of fiber reinforced composites: A review, Journal of Marine Science and Engineering, 8(1), p. 26. DOI: 10.3390/jmse8010026. T R EFERENCES

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