Study on the Micromechanical Interface Response Behavior of Propellants Based on Nano-Impact Testing

This study utilizes a nano-impact experimental platform to investigate the stress-strain response of propellant interfaces with two different binders, HTPE and GAP. The mechanical behavior of HTPB-AP and GAP-AP interfaces was examined at the nano-scale under varying strain rates, with experiments conducted at rates up to 100 s^-1. These experiments successfully captured the strain rate-dependent mechanical properties of both propellant components and their interfaces. The experimental results align well with the rate-dependent power-law viscoplastic constitutive models developed for HTPE, HTPE/AP, GAP, and GAP/AP interfaces, validating the model's effectiveness in describing the viscoplastic behavior of these materials and their interfaces. The study demonstrates that interfaces generally exhibit lower stress responses compared to bulk materials. HTPE shows higher initial stress responses and more pronounced strain hardening than GAP.