Assignment of chapter 3 Table 2.1 Typical Mechanical Properties of a Unidirectional Lamina (SI System of Units) Glass/ Boron/ Property Symbol Units epoxy epoxy Graphite/ epoxy Fiber volume fraction V 0.45 0.50 0.70 Longitudinal elastic modulus E GPa 38.6 204 181 Transverse elastic modulus E GPa 8.27 18.50 10.30 Major Poisson's ratio V12 0.26 0.23 0.28 Shear modulus G12 GPa 4.14 5.59 7.17 Ultimate longitudinal tensile strength (ult MPa 1062 1260 1500 Ultimate longitudinal compressive strength (ult MPa 610 2500 1500 Ultimate transverse tensile strength (0%)ult MPa 31 61 40 Ultimate transverse compressive strength (0%)ulk MPa 118 202 246 Ultimate in-plane shear strength (512)ult MPa 72 67 68 Longitudinal coefficient of thermal expansion m/m/C 8.6 6.1 0.02 Transverse coefficient of thermal expansion m/m/"C 22.1 30.3 22.5 Longitudinal coefficient of moisture expansion Transverse coefficient of moisture expansion B m/m/kg/kg 0.00 0.00 0.00 m/m/kg/kg 0.60 0.60 0.60 (Source: Reprinted with permission from Tsai, S. W. and Hahn, H. T., Introduction to Composite Materials, Technomic Publishing Co., Inc., Lancaster, PA, Table 1.7, p. 19; Table 7.1, p. 292; Table 8.3, p. 344.) 3-1 Predict four elastic constants for Graphite/epoxy lamina with V=0.70, using Rectangular block RVE model Halphin and Tsai model respectively. E=230; E =3.4; E = 22; G = 12 (GPa) v f12 = 0.3 v = 0.3 3-2 Find out of a glass/epoxy lamina with V=0.45. E, = 85GPa, v = 0.2, (})ult E=3.4GPa, v, 1550MPa, ()ult 35MPa = m 0.3, (0)=72MPa, (tm)ult = 34MPa 3-3 Find (of a glass/epoxy lamina with V=0.45, using Transverse matrix fracture mode, Fiber extension micro-buckling mode, Fiber shear micro-buckling mode and Shear failure of fiber and matrix model respectively. E = 85GPa, v = 0.2, (07) ult = 1550MPa, (f)ult m m == = 34MPa E = 3.4GPa, v = 0.3, (m) ult = 72MPa, (m)ult Shear failure of fiber and model: (ult = 2[()ults + (Tm)ult Vm] f 35MPa matrix 3-4 Find ul and ult of a glass/epoxy lamina with V=0.45, using rectangular block model, Empirical formula and Empirical simple estimation, respectively. E = 85GPa, v, = 0.2, (07) ult = 1550MPa, (t)ult E=3.4GPa, v, = m = 35MPa = 0.3, (0%) = 72MPa, (tm)ult = 34MPa