The Effect Of Interface Properties On Elastic Modulus Of In-situ Particales Aluminum Composites

In-situ particle reinforced aluminum matrix composite materials has become one of research hotspots of composite material because of its excellent mechanical properties and physical properties, easy to process and obviously low cost advantage. Interface properties have a significant impact on the elastic modulus of the composite, while the current main research object is adding particles reinforced aluminum matrix composites. In this paper, the in situ particle reinforced aluminum matrix composites microcosmic structure was observed, and the in situ particle reinforced aluminum matrix composites experimental research was conducted on the composite elastic modulus. On the basis of experimental study, the three-dimensional and two-dimensional RVE finite element models have been established. Combined with the mixed law model, the influences of microstructure parameters such as interface on in situ particle reinforced aluminum matrix composites modulus of elasticity have been simulated and calculated. The model is proved to be right by comparing it with the experimental result. And the model is used to simulate the effect of elastic-plastic interface and interface with gradient modulus on modulus of elasticity of in-situ SiCp/7075 Al composite materials. Research contents and research conclusions are as follows:(1)In-situ TiB2/A356 composite material were prepared by melt reaction method, and use JSM-7001 F scanning electron microscopy(SEM) to scan the composite materials. Using electronic universal testing machine for each specimen tensile experiment was carried out, and gets its modulus of elasticity. The three-dimensional and two-dimensional RVE finite element model have been established.Combined with the mixed law model, the effect of interface modulus on in-situTiB2/A356 composite modulus of elasticity has been simulated and calculated, and arrive at the stress and strain field distribution details about composites microstructure cell. The model is proved to be right by comparing it with the experimental result, and the model is used to predict the effect of interface performance on elastic modulus of TiB2/A356 composite materials when the particle volume fraction is larger.(2)And the model is also used to simulate the effect of elastic-plastic interface on modulus of elasticity of in-situ SiCp/7075 composite materials. The elasticity modulus of in-situ aluminum matrix composite increases with the interfacial elasticity modulus increase, and the more particle volume fraction is, the more significant the influence of the interface is. With the increase of particle volume fraction, the value of minimum interface/matrix modulus decreases, and it is not limited to the range of 20%-30%. When the particle volume fraction is greater, compared with pure-elastic interface, elastic-plastic interface can significantly reduce the elastic modulus of the in-situ aluminum matrix composite.(3)Due to the performance of the interface layer is continuous variation with position, this article assumes that the interface modulus as a function, gradient function in numerical calculation, and makes the discretization of the function. For the convenience of using software to characterize interface modulus gradient change, this paper established the containing gradient interface layer ax symmetric RVE model by making interface layer. The prediction results of in-situ aluminum matrix composite elasticity modulus whose interface is gradient modulus is lower than the prediction results of composite modulus with corresponding homogeneous interface layer.