Molecular spectroscopy-based temperature diagnosis of hypervelocity impact products in Al/PTFE reactive structural materials

Abstract

This study proposes a temperature diagnostic method for the reaction products of Al/PTFE reactive structural materials under hypervelocity impact (2.68–4.96 km/s) by integrating molecular spectroscopy theory with experimental data. Hypervelocity impact experiments were conducted using a two-stage light gas gun, and transient spectral measurements captured the radiation spectra of Al/PTFE impacting aluminum plates, revealing characteristic spectral lines of AlO (B2Σ+–X2Σ+) and C2d3Πg−a3Πu. Theoretical calculations employed high-precision ab initio methods (HF/CASSCF/MRCI+Q with the aug-cc-pVQZ-DK basis set) to derive the potential energy curves, transition dipole moment functions, spectroscopic constants, partition functions, and spectral line intensities in the ultraviolet region for AlO. These calculations provide a robust foundation for temperature diagnostics. The results support the analysis of the energy release mechanisms and damage efficiency of Al/PTFE under hypervelocity impact.