Dynamic Fracture Analysis Of Functionally Graded Materials Using Peridynamic Theory

The major difference between functionally graded materials and traditional materials,including composites,is the gradient distribution of material properties with respect to spatial coordinates,thereby eliminating the obvious interface problems in composites where different materials are combined.At the same time,however,it also causes the complexity of the mechanical analysis of functionally graded materials.With the field FGMs applied more widely,studies on the mechanical properties of FGMs is also essential,especially in the fracture behavior under dynamic loads of research.This paper is based on bond-based peridynamics of FGMs simulation analysis,and achieved the following results:(1)A positive weighting function and an inverse weighting function mode are proposed in order to make more reasonable use of the Young's modulus and fracture toughness of the functionally graded material.The convergence analysis of the functionally graded materials was analyzed based on peridynamics.Selecting different micro-modulus functions to analyze the influence of the weighting function on its results.By contrast Triangle micro modulus is preferably in the simulation stability,better performance for FGMs simulations using the inverse weighted function model.(2)An optimized weighted peridynamics model is used to analyze the lower reaction mechanism and damage of FGMs under dynamic tensile load.The influence of the initial crack length and position on the failure of the specimen was analyzed.The initial single crack length had a significant effect on the specimen damage,but had little effect on the crack path.And from the stress cloud diagram,the stress wave propagates faster on the larger side of the material parameter.(3)The influence of the initial model of the double crack fracture,the stress wave propagation parameter larger side of the material faster,can be found in the gradient material parameters significantly large side stress crack tip stress concentration occurs first.The double crack tip stress field interacts with each other,causing the crack path to deflect.When double cracks are staggered,they are significantly easier to crack and break than double cracks on the same side of the model.(4)By analyzing the gradient form as a linear function,an exponential function,and a trigonometric function,it is found that the gradient function form has a greater influence on the double-crack model.In the initial single crack,the triangular function is distinct from the linear and exponential functions;in the initial double cracks,the three gradient forms are all significantly different.Under conditions described by the same model and type of load,and reasonable arrangement of parameters in the form of a distribution gradient material can effectively improve the mechanical properties of the material.