PSI - Issue 14

Arun Kumar Singh et al. / Procedia Structural Integrity 14 (2019) 720–728 Arun Kumar Singh et al./ Structural Integrity Procedia 00 (2018) 000–000

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Table 5. Plane strain fracture toughness (K IC , MPa√m).

P max (N)

K 1c MPa√m

K max MPa√m

S No.

Specimen Name

Sample Size

Depth of Cut (a) (mm)

Notch root radius (ρ) (μm)

a/W

P Q (N)

Width (W) (mm) 10.25 10.20 10.25 10.25 10.20 10.25 10.25 10.20 10.25

Thickness (B) (mm)

1 HY4.5SP01 HY4.5SP02 HY4.5SP03 2 HY5.0SP01 HY5.0SP02 HY5.0SP03 3 HY6.0SP01 HY6.0SP02 HY6.0SP03

5.70 5.70 5.50 5.70 5.60 5.60 5.70 5.60 5.50

4.5 4.5 4.5 5.0 5.0 5.0 6.0 6.0 6.0

340 340 340 340 340 340 340 340 340

0.439024 0.441176 0.439024 0.487805 0.490196 0.487805 0.585366 0.588235 0.585366

126.57 122.02 113.09

129.19 134.16 118.76

1.941 1.888 1.798 1.369 1.541 1.662 1.551 1.283 1.475

1.982 2.076 1.888 1.518 1.679 1.839 1.734 1.600 1.649

69.89 76.86 84.55 62.73 50.29 57.56

77.23 83.78 93.54 70.11 62.73 64.37

5. Conclusions i.

An optimization approach, based on the Box-Behnken design of experiments and surface response method, has been used for optimization of process parameters for moulding of UHMWPE and p-aramid based hybrid composite. ii. The optimum flexural strength 62.75 MPa obtained at the following process parameters: 120 o C temperatures, 12.7 minutes time and 14.2 MPa pressure. iii. The fracture toughness has been found independent of the ρ below the ρ 0 of 340 µm for the UHMWPE and p-aramid based hybrid composite and increases linearlywiththesquarerootofnotchrootradiusfor ρ greater than 340 µm. iv. The K Ic of the hybrid compositehas been determined to be 1.52MPa√m. In the hybrid composite of materials the ratio K Ic /σ f found to be the same. This clearly reveals that, the fracture behaviour is controlledby LEFM. References Annadurai G., Sheeja, R.Y.,1998.“Use of Box-Behnken design of experiments for the absorption of vertofix red using biopolymer” Bioprocess Engineering 18, 463-466. Aslan, N., Cebeci, Y.,2006.“Application of Box-Behnken design and response surface metholodgy for modelling of some Turkish coals” Mining engineering department, Cumhuriyet University, Turkey, Science Direct. Bolotin, V.V., 2001.“Mechanics of delaminations in laminate composite structures” Mechanics of Composite Materials 37(5/6), 367–380. Bahramiana, N., Ataib, M., Reza, M., 2015.“Ultra-high-molecular-weight polyethylene fiber reinforced dental composites: Effect of fiber surface treatment on mechanical properties of the composites”Dental Materials 31, 1022–1029. Box, G.E.P., Behnken, D.W., 1960. “Some new three level design for the study of quantitative variables” Technometrics, 2, 455-475. Box, G.E.P., Draper, N.R., 1959. “A basis for the selection of a response surface design” J American Stat. Assoc, 54, 622-654. Box, G.E.P., Hunter, J.S.,1957.“Multifactor experimental design for exploring response surfaces” Ann. Math. Statistics 28, 195-241. Damani, R., Gstrein, R. and Danzer, R., 1996.“Critical notch root radius in SENB-S fracture toughness testing” J. European Ceramic Society 16(7), 695–702. Eugenio, D., Azevedo, S., Sergio, F., M., 1999.“Notch sensitivity of carbon/epoxy fabric laminates” Composite Science Technology, 59(8), 1143–1151. Hancox, N. L., 1981.“Fibre Composite Hybrid Material” Applied Science Press, London. Kim, B.W., Mayer, A.H., 2003.“Influence of fiber direction and mixed-mode ratio on delamination fracture toughness of carbon/epoxy laminates” Composite Science Technology 63(5), 695–713. Lagace, P. A., 1986.“Notch sensitivity of graphite/epoxy fabric laminates” Composite. Science Technology 26(2), 95–117. Mallick, P. K., 2010.“Fiber-reinforced composites: materials, manufacturing, and design” CRC press. Miao, C., Hamad, W.Y., 2013.“Cellulose reinforced polymer composites and nanocomposites: a critical review” Cellulose 20, 2221–2262. Marissen, R., 2011.“Design with ultra strong polyethylene fibers” Material Sciences and Applications 02, 319–330.