A laminated [0/90/0/90]s graphite/epoxy beam is 1 mm thick, is 20 mm wide, and has 0.125 mm thick plies. The lamina properties are E1 = 180 GPa, E2 = 10 GPa, ν12 = 0.28, G12 = 7 GPa Xt = 1700 MPa, Xc = 1400 MPa, Yt = 40 MPa, Yc = 230 MPa (a) Determine the flexural modulus of the beam (b) How could the flexural modulus be improved without changing the ply materials, the number of plies, or the ply orientations? (c) Using the Maximum Stress Criterion for each ply, determine the magnitude of the maximum allowable bending moment that the beam can withstand. Which ply fails first?

A laminated [0/90/0/90]s graphite/epoxy beam is 1 mm thick, is 20 mm wide, and has 0.125 mm thick plies. The lamina properties are E1 = 180 GPa, E2 = 10 GPa, ν12 = 0.28, G12 = 7 GPa Xt = 1700 MPa, Xc = 1400 MPa, Yt = 40 MPa, Yc = 230 MPa (a) Determine the flexural modulus of the beam (b) How could the flexural modulus be improved without changing the ply materials, the number of plies, or the ply orientations? (c) Using the Maximum Stress Criterion for each ply, determine the magnitude of the maximum allowable bending moment that the beam can withstand. Which ply fails first?

Materials Science And Engineering Properties

1st Edition

ISBN:9781111988609

Author:Charles Gilmore

Publisher:Charles Gilmore

Chapter12: Composite Materials

Section: Chapter Questions

Problem 2CQ

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