Gasless Combustion in Ti-xSi Powder Mixtures

摘要

Gasless combustion in the Ti-Si system was investigated by high-speed video recording (250 frames per second) followed by frame-by-frame treatment of the records. Steady-state combustion was observed when the combustion temperature, T_c, was above the melting points of Ti and Si. Two different modes of unsteady combustion were found when T_c was higher than the melting point of Si but lower than the melting point of Ti: (1) combined quasi-spinning combustion at Ti excess and (2) meso-scintillating combustion at Si excess. The combustion faded when the adiabatic combustion temperature, T_(ad), became close to a lowest melting point in the system. All of the observed combustion modes can be rationalized in terms of a micro-heterogeneous model. Proposed are the methods for experimental diagnostics of 3D combustion waves inside an opaque sample and distinguishing between truly spinning, quasi-spinning, and other combustions modes.