With the increasingly widespread application of rubber in many fields,there is a growing demand for quantitative characterization of temperature-dependent mechanical properties in high-temperature service environments...With the increasingly widespread application of rubber in many fields,there is a growing demand for quantitative characterization of temperature-dependent mechanical properties in high-temperature service environments.The critical tearing energy is an important criterion for determining whether rubber materials will experience tearing instability,while tear strength is a key parameter for rubber materials to resist tearing.It is necessary to quantitatively characterize their evolution with temperature.Current theoretical research mainly relies on fitting a large amount of experimental data,which is not convenient for engineering applications.Therefore,in this work,a temperature-dependent critical tearing energy model is firstly developed based on the force-heat equivalence energy density principle.This model considers the equivalent relationship between the critical tearing energy required for crack instability propagation and the thermal energy stored in the rubber material.It is demonstrated that our model has higher prediction accuracy when compared to other models.Furthermore,combining with the Griffith fracture theory,temperature-dependent tear strength models applicable to three different crack modes are separately established.These models are validated using experimental data for Mode I opening cracks and ModeⅢtearing cracks,and good consistency is achieved.Additionally,a quantitative analysis of the influence of elastic modulus on tear strength at different temperatures is conducted.This work provides a reliable way for predicting temperature-dependent tearing instability behavior and offers beneficial suggestions for improving the tear strength of rubber materials at different temperatures.展开更多
基金the National Natural Science Foundation of China(12172069)the Graduate Scientific Research and Innovation Foundation of Chongqing(CYS23078)for their support in this research.
文摘With the increasingly widespread application of rubber in many fields,there is a growing demand for quantitative characterization of temperature-dependent mechanical properties in high-temperature service environments.The critical tearing energy is an important criterion for determining whether rubber materials will experience tearing instability,while tear strength is a key parameter for rubber materials to resist tearing.It is necessary to quantitatively characterize their evolution with temperature.Current theoretical research mainly relies on fitting a large amount of experimental data,which is not convenient for engineering applications.Therefore,in this work,a temperature-dependent critical tearing energy model is firstly developed based on the force-heat equivalence energy density principle.This model considers the equivalent relationship between the critical tearing energy required for crack instability propagation and the thermal energy stored in the rubber material.It is demonstrated that our model has higher prediction accuracy when compared to other models.Furthermore,combining with the Griffith fracture theory,temperature-dependent tear strength models applicable to three different crack modes are separately established.These models are validated using experimental data for Mode I opening cracks and ModeⅢtearing cracks,and good consistency is achieved.Additionally,a quantitative analysis of the influence of elastic modulus on tear strength at different temperatures is conducted.This work provides a reliable way for predicting temperature-dependent tearing instability behavior and offers beneficial suggestions for improving the tear strength of rubber materials at different temperatures.