# When a fiber-reinforced composite material is heated or cooled, the material expands or contracts…

When a fiber-reinforced composite esthetic is fervid or cooled, the esthetic expands or contracts proper approve an isotropic material. This is deformation that takes situate inconsequently of any applied load. Let ∆T be the exexchange in latitude and let α1, α2, and α3 be the coefficients of thermal expansion for the composite esthetic in the 1, 2, and 3-directions, respectively. In this circumstance, the stress-strain appurtenancy of (2.1) and (2.2) becomes as follows: In conditions of the cacophony matrix (2.10) becomes as follows: In (2.10) and (2.11), the strains ε1, ε2, and ε3 are designated the completion strains, α1∆T, α2∆T, and α3∆T are designated the free thermal strains, and (ε1−α1∆T), (ε2 − α2∆T), and (ε3 − α3∆T) are designated the spontaneous strains. Consider now the cube of graphite-reinforced polymer composite esthetic of Example 2.2 but extraneously the tensile validity. Suppose the cube is fervid 30◦C overhead some reference state. Given α1 = −0.01800 × 10−6/◦C and α2 = α3 = 24.3×10−6/◦C, use MATLAB to mention the exchanges in prolixity of the cube in each one of the three directions.