Strain-rate dependent dynamic constitutive model of tempered glass

Tempered glass is essentially different from float glass in dynamic mechanical properties, although it is toughened float glass made by physics and they have the same chemical composition. The dynamic mechanical properties of tempered glass are investigated in this paper by using the modified techniques of the Split Hopkinson Pressure Bar (SHPB), and the curves of stress-strain are obtained in various strain rates. Experimental results show that tempered glass is sensitive to strain rates and its dynamic curves of stress-strain are nonlinear. Further study reveals the phenomenon of “pseudo-plastic yield” is completely different from that of ductile materials, and dynamic Young’s modulus and dynamic compressive strength of tempered glass increase with the increasing strain rates. Based on the damage mechanics theory, a kind of constitutive model with damage of tempered glass is given. A strain rate-dependent constitutive model with damage of tempered glass is created by the use of polynomial fitting, according to SHPB experimental results.