MODELING OF CONSOLIDATION OF NANO-SIZE POWDERS

纳米粉体固结的建模研究作者：Eugene a . Olevsky，圣地亚哥州立大学该研究项目旨在发展纳米粉体固结的广义理论。该模型方法考虑了纳米粉末烧结后期典型的团聚现象、可能的原位损伤发展和晶粒生长的不稳定性。确定性（连续介质力学）和随机方法都用于分析材料的行为。实验输入减少到最小数量的自由烧结和烧结锻造试验，以确定纳米粉末的本构特性。所发展的理论概念将通过三种不同类型的纳米粉末材料：金属、陶瓷和金属-陶瓷复合材料进行实验来验证。所开发的计算机代码将能够预测和优化宏观形状畸变、密度、团聚特性、晶粒尺寸和晶粒形态空间分布。提议的努力包括在线过程（巩固）控制的基础，用于纳米材料相关行业的广泛纳米粉末组件设计。该项目的实现将为在加工过程中纳米结构的演变提供重要的见解，并且从实用的角度来看，将有机会降低由于固化优化而产生的高生产成本。该计划有望为圣地亚哥州立大学通用机械工程课程的材料工程领域的进步做出贡献。将开设一门新的粉末加工力学研究生课程。本科生和研究生都将参与理论和实验研究。学生将参与与PI合作优化纳米粉末巩固的当地工业实习。该项目将有助于加强与加州大学圣地亚哥分校的联合博士课程。

MODELING OF CONSOLIDATION OF NANO-SIZE POWDERSPI: Eugene A. Olevsky, San Diego State UniversityThe research program is aimed at the development of a generalized theory of consolidation of nano-powders. This model approach takes into consideration the agglomeration phenomena, possible in-situ damage development and instability of the grain growth typical for final stages of the nano-powders sintering. Both deterministic (continuum mechanics) and stochastic approaches are used for the analysis of the material behavior. The experimental input is reduced to a minimal number of free sintering and sinter-forging tests necessary to determine the constitutive properties of nano-powders. The developed theoretical concepts will be verified by the experiments conducted with three different types of nano-powder materials: metals, ceramics and metal-ceramic composites. The developed computer codes will enable the prediction and optimization of macroscopic shape distortions, density, agglomerate characteristics, grain size and grain morphology spatial distributions. The proposed effort includes the basis of an on-line process (consolidation) control for a wide range of nano-powder component designs, which are used in nano-materials related industries. Realization of the project will provide an important insight on in-processing nano-structures evolution and, from the practical point of view, will render a chance to lower still high production costs due to the optimization of consolidation.The proposed program is expected to contribute to the advancement of the Materials Engineering area of the general Mechanical Engineering curriculum of the San Diego State University. A new graduate course on Mechanics of Powder Processing will be developed. Both undergraduate and graduate students will participate in the theoretical and experimental investigations. Students will be involved in internships by local industries collaborating with PI on optimization of nano-powder consolidation. The project will contribute to the enhancement of the Joint Doctoral Program with University of California, San Diego.