The Finite Element Analysis Of Mechnical Behavior Of Mg-baced Composites Reinforced With Short Fiber

In this disquisition, a finite element model of Mg-matrix composite reinforcedwith short fiber is developed in ansys10.0. used to find the stress and strain statusaround the fiber. By observing the location and intensity of the stress concentration toassess the possibility of cracks.and mainly analysis he effect of the differentparameters of the fiber on the interaction zone and stress saturation region.And whenthe composite have different forms of crack, the stress and strain distribution near thecrack The line elastic material model is used in this atical.The conclutions are as follow:Radius of the fiber determines the size of the interaction zoon between the fiberand the matrix, has nothing to do with the length of the fiber. For the fibers withthe same radius, the length just determines the size of the region of saturation stress.The Radius is greater, the sizes of the interaction regions is greater: the greater thelength, the greater the stress saturated zone. But they both can’t effect the saturationstress. This is consistent with the findings to the aspect ratio.The matching of theelastic modulus between the fiber and the matrix has little impact on the size of theinteraction area, but has significant effect on the stress value in the interactionzoon.The greater the difference of The elasticity modulus the greater the stress in thesame loacation, the stronger the stress concentration, the greater the probability ofcracks in the interaction region. Applied load did not affect the size of the interactionzoon,just linear change the size of the local stress.The shape of the end of the fiber has a great influence on the stress value here。If the fiber ends is flat cross-section,there will be very strong stress concentration atthe edge of the end of the edge, so that the material debonding occurs very early on inhere, and cracks. If the shape of the end to be a spherical or oval,the stressconcentration can be significantly improved.Compared with a flat cross-section end,the maximum stress can be reduced by half. This greatly reduced the probability ofcracks here in the material and thus greatly improve the ability of materials towithstand loads.For the calculation of the elastic modulus of the composite,the loadingconditions has obvioce infuluence on the calculated results.The stress and straindistribution under bending loads was significantly different with the status undertensile load.It does not have the saturation zoon and the interaction zoon. Thelayered stress distribution in fiber radial is found, almost the same shear stress across the entire contact surface..And stress concentration in the fiber end does not exist. Atthe top of the crack there will be a strong stress concentration nuder loading when thecomposite containing cracks.The crack propagation becomes complicated because theadded fiber, thereby enhancing the toughness of the material.