Recent progress on impact induced reaction mechanism of reactive alloys

In recent years, in order to improve the destructive effectiveness of munitions, the use of new types of destructive elements is an important way to improve destructive effectiveness. As a new type of reactive material, reactive alloy contains a large portion of reactive metal elements (Al, Mg, Ti, Zr, etc.), which breaks up under high-velocity impact conditions, generating a large number of high-temperature combustible fragments, which undergo a violent combustion reaction with air. Compared with traditional metal polymers (Al-PTFE) and other reactive composites, it has higher density and strength, excellent mechanical properties and broader application prospects. Currently, researchers have mainly investigated the impact energy release mechanism of reactive alloys through impact tests, and found that there are several important stages in the process of the material from fragmentation to reaction, i.e., impact fragmentation of the material, rapid heating and combustion reaction. This paper focuses on three problems that need to be solved in the impact-induced energy release process of reactive alloys, namely: the fragmentation mechanism and size distribution law of the fragments produced by the impact of the material on the target, the relationship between the transient temperatures and the size of the fragments, and the reaction temperatures and size thresholds of the fragments to undergo the chemical reaction. The current status of the research of the above problems is reviewed, some potential directions to reveal the impact induced reaction mechanism of reactive alloy is discussed.