Dissociation Behavior Of Tyre Rubber Under Ultra-high Water Jet Impact

With the rapid development of China’s automobile industry in recent years, the annual amount of waste radial tires also increased year by year, the ability to effectively deal with the recovery and recycling is related to recycling of resources and environmental pollution control. Therefore, this paper will use pressure water jet test method for radial tires crushing. Crushing process mechanism is complex, the material stress state and the dissociation behavior during the process of crushing is discussed.Finite element numerical simulation method is used to study the tread rubber stress distribution during water jet impingement process, analyzed the material crushing characteristics. Using scanning electron microscopy, the relationship between material stress distribution, fracture surface morphology and dissociation way is analyzed, and preliminarily verified the existence of brittle fracture. The rubber stress-strain data over a wide range of strain rates is obtained by split Hopkinson pressure bar test (SHPB).By analyzing the dynamic response, a dynamic constitutive model is built based on Mooney-Rivlin. And do statistical analysis to experimental data using SPSS, the dynamic constitutive model parameters are fitted. Further analysis of the mechanical properties, the stress wave propagation criterion and microscopic, the material brittle fracture is verified. And analyzed the formation of fine rubber powder.The results show that:The material generated debacle under compressive stress during crushing, jet’s sustained injection to the crack resulted tensile failure. Section morphology shows the presence of damage along the grain and transgranular fracture, crack propagation area showed typical radial brittle fracture surface. SHPB test results show materials exhibit nonlinear stress-strain relation, yield stress increases with strain rate increased from89MPa345MPa, with a strain rate hardening effect and brittle fracture characteristics, according to the analysis of stress wave propagation criterion, material particle velocity is more than2500m/s at the maximum compressive stress larger than the ductile-brittle transition critical velocity, indicating that ductile-brittle transition occurs in the material. Therefore, ultra-high pressure water jet technology can make rubber material more than200mesh ultra-fine powder at a brittle state.