The fracture behavior of polymer-bonded explosive(PBX) seriously affects the safety and reliability of weapon system.The effects of interface debonding and initial meso-damage on the fracture behavior of PBX under qua...The fracture behavior of polymer-bonded explosive(PBX) seriously affects the safety and reliability of weapon system.The effects of interface debonding and initial meso-damage on the fracture behavior of PBX under quasi-static tension are studied using numerical method.A twodimensional representative volume element(RVE) is established based on Voronoi model in which the component contents could be regulated and the particles are randomly distributed.A nonlinear damage model of polymer matrix relative to matrix depth between particles is constructed.The results show that the simulated strain-stress relation is coincident with experiment data.It is found that interface debonding leads to the nucleation and propagation of meso-cracks,and a main crack approximately perpendicular to the loading direction is generated finally.The interface debonding tends to occur in the interface perpendicular to the loading direction.There seems to be a phenomenon that strain softening and hardening alternatively appear around peak stress of stress and strain curve.It is shown that the initial damages of intragranular and interfacial cracks both decrease the modulus and failure stress,and the main crack tends to propagate toward the initial meso-cracks.展开更多
Interface debonding between particle and matrix in composite propellant influences its macroscopic mechanical properties greatly. For this, the laws of interface cohesive damage and failure were analyzed. Then, its mi...Interface debonding between particle and matrix in composite propellant influences its macroscopic mechanical properties greatly. For this, the laws of interface cohesive damage and failure were analyzed. Then, its microscopic computational model was established. The interface mechanical response was modeled by the bilinear cohesive zone model. The effects of interface properties and particle sizes on the macroscopic mechanical behavior were investigated. Numerical simulation of debonding damage evolution of composite propellant under finite deformation was carried out. The debonding damage nucleation, propagation mechanism and non-uniform distribution of microscopic stress-strain fields were discussed. The results show that the finite element simulation method based on microstructure model can effectively predict the trend of macroscopic mechanical behavior and particle/matrix debonding evolution process. It can be used for damage simulation and failure assessment of composite propellants.展开更多
文摘The fracture behavior of polymer-bonded explosive(PBX) seriously affects the safety and reliability of weapon system.The effects of interface debonding and initial meso-damage on the fracture behavior of PBX under quasi-static tension are studied using numerical method.A twodimensional representative volume element(RVE) is established based on Voronoi model in which the component contents could be regulated and the particles are randomly distributed.A nonlinear damage model of polymer matrix relative to matrix depth between particles is constructed.The results show that the simulated strain-stress relation is coincident with experiment data.It is found that interface debonding leads to the nucleation and propagation of meso-cracks,and a main crack approximately perpendicular to the loading direction is generated finally.The interface debonding tends to occur in the interface perpendicular to the loading direction.There seems to be a phenomenon that strain softening and hardening alternatively appear around peak stress of stress and strain curve.It is shown that the initial damages of intragranular and interfacial cracks both decrease the modulus and failure stress,and the main crack tends to propagate toward the initial meso-cracks.
基金Sponsored by the General Armament Department Advanced Research Project (20101019)
文摘Interface debonding between particle and matrix in composite propellant influences its macroscopic mechanical properties greatly. For this, the laws of interface cohesive damage and failure were analyzed. Then, its microscopic computational model was established. The interface mechanical response was modeled by the bilinear cohesive zone model. The effects of interface properties and particle sizes on the macroscopic mechanical behavior were investigated. Numerical simulation of debonding damage evolution of composite propellant under finite deformation was carried out. The debonding damage nucleation, propagation mechanism and non-uniform distribution of microscopic stress-strain fields were discussed. The results show that the finite element simulation method based on microstructure model can effectively predict the trend of macroscopic mechanical behavior and particle/matrix debonding evolution process. It can be used for damage simulation and failure assessment of composite propellants.
