Numerical Analysis On Tensile And Fatigue Properties Of Particles Modified Epoxy Composites

With the progress of science and technology,epoxies as one of the most commonly used epoxy polymer matrixes exhibit a lot of excellent mechanical properties by its amorphous and highly cross-linked characteristics,which help polymer matrix composites develop rapidly in civil engineering field,such as modified waterproofing,modified epoxy paint and so on.However the development of epoxies also subjects to certain restrictions due to its brittleness,pooring to resist crack initiation and growth in practice applications,and it is easier to fail before stress reaching the ultimate strength,especially under cyclic loading.In recent years,by adding all kinds of particles to modify the properties of epoxy resin has brought new opportunities for its development.In order to analyze the mechanism and variation on the epoxy resin modified by particles,the studies in this paper are as follows:Firstly,Written random distribution and automatic generating particles program in Python interface language,for ABAQUS finite element analysis software called to generate a two-dimensional representative volume element?RVE?model,based on Monte-Carlo method.Cohesive unit is used to simulate the weak interface for analyze the tensile properties of epoxy composites modified by nano-SiO₂ particles,under uniaxial tensile loading,nano-TiO₂and submicron rubber?LR?respectively,in terms of particle size and particle content in detail.And then,the model was verified to be effective by comparison with the related experimental results.Secondly,in view of the single-phase particles modified epoxy composites show some insufficient in individual aspects.Three mechanical indicators Young's modulus,tensile strength and elongation at break were used to analyze and forecast the properties of two-phase particles modified epoxy composites for"SiO₂+TiO₂","Si O₂+LR","TiO₂+LR",and to find its advantages by comparing to the single-phase particles modified situation.Finally,the effect of particles complex content proportion and particle diameter ratio were studied and analyzed at high and low fatigue stress for the"SiO₂+LR"and"TiO₂+LR"two-phase particles modified epoxy composites'fatigue properties,under sine wave cycle fatigue load,depending on corrected Miner law from fatigue damage accumulation theory,to find out the factors controlling the fatigue life of the composites.