Science. 1990 Sep 21;249(4975):1406-9. doi: 10.1126/science.249.4975.1406.
Real-time synchrotron diffraction has been used to monitor the phase transformations of highly exothermic, fast self-propagating solid combustion reactions on a subsecond time scale down to 100 milliseconds and in some instances to 10 milliseconds. Three systems were investigated: Ti + C --> TiC; Ti + C + xNi --> TiC + Ni-Ti alloy; and Al + Ni --> AlNi. In all three reactions, the first step was the melting of the metal reactants. Formation of TiC in the first two reactions was completed within 400 milliseconds of the melting of the Ti metal, indicating that the formation of TiC took place during the passage of the combustion wave front. In the Al + Ni reaction, however, passage of the wave front was followed by the appearance and disappearance of at least one intermediate in the afterburn region. The final AlNi was formed some 5 seconds later and exhibited a delayed appearance of the (210) reflection, which tends to support a phase transformation from a disordered AlNi phase at high temperature to an ordered CsCl structure some 20 seconds later. This new experimental approach can be used to study the chemical dynamics of high-temperature solid-state phenomena and to provide the needed database to test various models for solid combustion.
实时同步加速器衍射已被用于在亚秒级（低至 100 毫秒，某些情况下甚至低至 10 毫秒）时间尺度上监测高放热、快速自蔓延固体燃烧反应的相变。研究了三个系统：Ti + C --> TiC；Ti + C + xNi --> TiC + Ni-Ti 合金；以及 Al + Ni --> AlNi。在所有三个反应中，第一步是金属反应物的熔化。在前两个反应中，TiC 的形成在 Ti 金属熔化后的 400 毫秒内完成，这表明 TiC 的形成发生在燃烧波前通过的过程中。然而，在 Al + Ni 反应中，波前通过后，在后燃区至少出现了一种中间产物。最终的 AlNi 是在 5 秒后形成的，并且表现出（210）反射的延迟出现，这倾向于支持在高温下从无序 AlNi 相到大约 20 秒后有序 CsCl 结构的相变。这种新的实验方法可用于研究高温固态现象的化学动力学，并提供测试各种固体燃烧模型所需的数据库。
