Experiment and numerical simulation of curing process of cast PBX

To research the change rule of temperature field and stress field in the curing process for cast PBX (Polymer Bonded Explosive, PBX), the temperature field in the curing process of cast PBX under 60℃ was tested by Bragg gratings. The numerical simulation of temperature fields and stress fields under different heat transfer coefficient during curing process of the cast PBX explosive were conducted by finite element method. Results show that in the first stage of curing reaction, the temperature of the grain is higher than 60℃. The temperature in the central portion of the grain reach 65℃. The decreasing trend of temperature is revealed from the center to internal wall of the mold. Largest temperature gradient appears at the 3.88×10⁵ s. Stress concentration area is mainly located in the bottom of the grain. The effective stress concentration area and the maximum effective stress enlarge with increasing the heat transfer coefficient between model and grain. When the value of heat transfer coefficient is 12 W·m^-2·K^-1, the grain has the maximum stress concentration area at 3.88×10⁵s and the maximum effective stress is 6.69 kPa.