Impregnation of fibrous fillers with polymeric binders 6. Effect of parameters of ultrasound treatment on strength properties of wound fibrous composites

Conclusion Tests of annular PCM specimens — fiberglasses and organoplastics formed by the method of wet winding using low-frequency ultrasound — were conducted. Three alternate US-impregnation schemes were investigated. Optimal alternate schemes and insonification parameters were established experimentally: frequency, amplitude, intensity, and time. Optimization was carried out on the basis of investigation of the relationships between the values of the tensile, compressive, bending, and interlayer-shear strengths, and also the relative content of filler as a function of treatment parameters. It was shown that deviation of insonification parameters from the optimal leads to a reduction in strength characteristics, as well as to a different character of specimen failure in tension and interlayer shear.The effect of US modification in producing PCM is provided by an increase in structural uniformity, and improvement of the strength and production characteristics of the polymer matrix, as well as by a reduction in the composite's effectiveness as a result of a reduction in the content of air inclusions and improvement of the binder's distribution across the section of the filler.For previous communication, see 9].Translated from Mekhanika Kompozitnykh Materialov, No. 4, pp. 724–731, July–August, 1989.