PSI - Issue 3

A.A. Ahmed et al. / Procedia Structural Integrity 3 (2017) 498–507 Author name / Structural Integrity Procedia 00 (2017) 000–000

507

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 since the stress vs. strain curves generated by testing the plain specimens (Fig. 5) were seen to be all characterised by a remarkable level of linearity up to the ultimate tensile stress, the mechanical behaviour of the investigated 3D printed PLA can be modelled successfully by directly using a simple linear-elastic constitutive law.

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 0 10 20 30 40 50 60 70 80 90 +2S D -2S D K c =3.2 MPa·m 1/2

K C [MPa ∙ m 1/2 ]

Deposition Angle,  p [  ]

Fig. 8. Influence of manufacturing angle  p on K C .

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