The point impact damage characteristics of panels made of chopped-glass-fiber- reinforced sheet molding compounds are evaluated qualitatively and quantitatively. In stead of the traditionally used dent depth, the surface damage area is identified as the primary parameter to characterize the impact damage of the SMC panels. Three techniques—radiographic, ultrasonic and crack enhancement—are used to measure the damage areas. The relative merits of the three methods are discussed.
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