Faculty Awards for Women Scientists and Engineers

美国国家科学基金会女科学家和工程师奖 认可得奖者在教学方面的卓越表现 和学术，以及潜在的研究，学术 专业，以及未来科学家和工程师的教育。 费伯博士在该奖项下的研究是针对 理解脆性材料的力学行为。 复相陶瓷和陶瓷的一个普遍特征- 金属系统的残余应力。 这种压力是由于 热膨胀不匹配的应变， 在加工过程中变形。 这种极端的压力 可以作为失败的来源，或者，可以增强 材料的抗断裂性取决于符号， 地点和压力的大小 鉴于关键的 残余应力的作用，这是必不可少的知道， 这些压力的大小和轮廓，以帮助我们 理解多相材料的断裂和增韧。 本研究的目的是表征残留 两种陶瓷基系统中的应力，特别是 其中残余应力通过施加 外部应力或热处理。 两个系统 提出：（1）碳化硅-二硼化钛复合材料， 其上的应力诱导微裂纹和应力消除 最近观察到微裂纹;和（2）氧化锆 在金属基材上的热障涂层， 高温暴露后残余应力发生变化。 x射线 衍射，必要时，中子衍射将是 用于测量残余应力的主要工具。 残余 应力分布及其在应力或热处理后的变化 将与测量的机械性能相关。

The NSF Faculty Awards for Women Scientists and Engineers recognizes the high quality of the awardee's record in teaching and scholarship, as well as potential research, the academic profession, and the education of future scientists and engineers. Dr. Faber's research under this award is directed at understanding the mechanical behavior of brittle materials. A ubiquitous feature of multiphase ceramics and ceramic- metal systems is residual stress. Such stresses are present due to thermal expansion mismatch strains that cannot be accommodated by deformation during processing. Such stresses in the extreme may serve as a source of failure, or alternatively, may enhance the fracture resistance of the material depending on the sign, the locale, and the magnitude of the stress. Given the pivotal role of residual stresses, it is essential to know both the magnitude and the profile of these stresses to aid in our understanding of fracture and toughening in multiphase materials. It is the aim of this study to characterize residual stresses in two ceramic-based systems, in particular, systems where residual stresses are altered through the application of an external stress or a thermal treatment. Two systems are proposed: (1) a silicon carbide - titanium diboride composite in which stress-induced microcracking and stress-relief on microcracking has recently been observed; and (2) zirconia thermal barrier coatings on metallic substrates in which the residual stresses change after high temperature exposure. X-ray diffraction and, when necessary, neutron diffraction will be the primary tools used to measure residual stresses. The residual stress profile and its change after stressing or heat treatment will be correlated to measured mechanical properties.