Liu J P, Kirchhoff J, Zhou L, Zhao M, Grapes M D, Dale D S, Tate M D, Philipp H T, Gruner S M, Weihs T P, Hufnagel T C
Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.
Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853, USA.
J Synchrotron Radiat. 2017 Jul 1;24(Pt 4):796-801. doi: 10.1107/S1600577517008013. Epub 2017 Jun 15.
A technique for measuring interdiffusion in multilayer materials during rapid heating using X-ray reflectivity is described. In this technique the sample is bent to achieve a range of incident angles simultaneously, and the scattered intensity is recorded on a fast high-dynamic-range mixed-mode pixel array detector. Heating of the multilayer is achieved by electrical resistive heating of the silicon substrate, monitored by an infrared pyrometer. As an example, reflectivity data from Al/Ni heated at rates up to 200 K s are presented. At short times the interdiffusion coefficient can be determined from the rate of decay of the reflectivity peaks, and it is shown that the activation energy for interdiffusion is consistent with a grain boundary diffusion mechanism. At longer times the simple analysis no longer applies because the evolution of the reflectivity pattern is complicated by other processes, such as nucleation and growth of intermetallic phases.
描述了一种利用X射线反射率在快速加热过程中测量多层材料中互扩散的技术。在该技术中，样品被弯曲以同时实现一系列入射角，散射强度记录在快速高动态范围混合模式像素阵列探测器上。多层材料的加热通过硅衬底的电阻加热实现，并由红外高温计监测。作为示例，给出了以高达200 K s的速率加热的Al/Ni的反射率数据。在短时间内，互扩散系数可由反射率峰值的衰减速率确定，结果表明互扩散的激活能与晶界扩散机制一致。在较长时间，由于反射率图案的演变因其他过程（如金属间相的形核和生长）而变得复杂，简单分析不再适用。
