Issue 53

K. Afaf et alii, Frattura ed Integrità Strutturale, 53 (2020) 66-80; DOI: 10.3221/IGF-ESIS.53.06

57% degradation of tensile strength, 10% increase in the strain at break, and 62% drop in Young's modulus. For the same duration, exposure of PMMA to solar (UV) radiation leads to a 50% drop in the stress at break and a 30% reduction in the strain at break, with a 47% drop in Young's modulus.

(a) (b) Figure 11: Effect of the duration of exposure to solar (UV) radiations on the mechanical properties of PMMA: (a) Stress at break, (b) Modulus of elasticity.

(a) (b) Figure 12: Effect of the duration of exposure to artificial (UV) lamp radiations on the mechanical properties of PMMA: (a) Stress at break, (b) Modulus of elasticity .

(a) (b) Figure 13: Comparing the effects of exposure time of PMMA to solar (UV) radiations and artificial (UV) lamp radiations on its mechanical properties: (a) Modulus of elasticity; (b) Stress at break.

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