Abstract
Most of structural FRP components are now compression-molded using SMC (Sheet Molding Compound). SMC are, however, characterized by considerable variations of the mechanical properties of molded parts. The advanced utilization of SMC demands to clearify the main factors controlling the variation of SMC properties. This paper deals with three kinds of SMC laminates of which charge ratios were 30, 60 and 90 percents. The main results obtained in this work are summarized as follows;
(1) SMC laminates showed the anisotropy of tensile strength which is directly related to the direction and also to the extent of SMC flow in molding. The relation between the anisotropy of laminate and material flow was complicated due to a localization phenomenon in SMC flow.
(2) The average and the coefficient of variation of the tensile strength of SMC laminates were calculated by use of the mixture laws of strength and its variation in FRP and were found to agree with the experimental data. The sensitivities of each variable on the tensile strength of SMC were computed. The simplified mixture laws of strength and its variation of SMC were proposed, which consist of the variables having high sensitivity.
