Активный тепловой контроль ударных повреждений в композиционных материалах, изготовленных методом 3D-печати

By using the technique of ultrasonic infrared thermography, it is demonstrated that the technology of 3D printing of composite parts allows avoiding the appearance of working hole micro-cracks which are conventional in the case of mechanical processing. The strength of composites toward impact damaging can be evaluated by relative variations of material thermal properties in defect areas. It is assumed that more powerful impacts lead to more severe defects and, respectively, greater variations in composite thermal effusivity and diffusivity. The damage resistance of Kevlar, carbon fiber reinforced polymer (CFRP) and their hybrid was comparatively evaluated. It was found that 15 J impact produced the 4/8 % variations of thermal effusivity/diffusivity in the hybrid composite. The thermal property variations in CFRP and Kevlar were 10/9 % and 15/11 % respectively.