RUI: Ultrasonic Study of Phase Transitions in Metals

采用直接电磁产生超声技术研究了马氏体相变温度附近镍铝合金中速度和衰减的前驱体效应。该技术不仅可以探测材料的体，还可以探测材料的表面，并将获得有关声子相互作用和与引起转变的缺陷相关的应变场的有价值的信息。为了确定这些合金中晶格稳定的条件，将测量弹性常数随静水压力和单轴压力的变化。与合作者的进一步研究将采用中子衍射工作来进一步表征研究项目中使用的单晶结构。

A direct electromagnetic generation of ultrasound techniques is used to study precursor effects in the velocity and attenuation in Nickel-Aluminum alloys near the martensitic phase transformation temperature. This technique probes not only the bulk but also the surface of the materials and will yield valuable information about both the interaction of phonons and the strain fields associated with the defects which cause the transformation. The variation of the elastic constants with hydrostatic and uniaxial pressure will e measured in order to determine the conditions for lattice stability in these alloys. Additional studies with collaborators will employ neutron diffraction work to further characterize the structure of single crystals used in the research project.