Quantitative Analysis And Investigation On Geometrical Morphology Of Pore In CFRP

Ultrasonic attenuation method is pursued in non-destruction testing of CFRP (Carbon Fiber Reinforced Polymer) porosity, but in the model the pore was assumed as circle, ellipse and disc shaped, therefore, the theoretical analysis result didn't agree with the experimental investigation. One important reason is that, the assumption deviates from the actual situation of pores geometrical morphology in present model. According to the latest study, the influence of geometrical morphology on strength and stiffness show differently. Much work has been done in the study of morphology, but there is much limitation. First of all, porosity excessive 2.5% in many studies, but the research is not enough under condition of porosity 2.5%, in the next place, the actual morphology of pores is much more complex, included many factors and content, lots of data statistical and metallographic observations will be needed, furthermore, in the most of study, rarely on the statistical and randomness of pore morphology.Based on analysis and summary on pore morphology investigation, the method of hot pressing was employed to prepare the 16-groups CFRP samples with porosity ranging from 0.03% to 4.96%, about 11-groups sample which porosity under 2.5%, and take 320 metallographs. Accepted the method of metallographic observation and statistical analysis respectively, the size, shape, number, location and distribution of pore have been investigated in CFRP. The result indicated that:(1)The range of length and equivalent width of pore are about 4-400μm and 2-100μm respectively.0.03%=P<0.5%, they centre at 10-50μm and 10-30μm respectively; 0.5%