Two Stages of SHS Process

In the after-burning zone, the fourth stage takes place - it is endothermic transition of s-TaNhex to 5-TaN(,ui3- 5-TaN(,ui, is thermodynamically stable only at high temperatures and can be retained after combustion due to very rapid cooling, in fact in a quenching mode. 

It should be noted that 5-TaN(,ui, has never been produced by conventional methods. We were the first who synthesized it by tantalum combustion in liquid nitrogen [56]. Its structure was investigated by Shekhtman using X-ray 

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