Fundamental Studies on Field Activated Sintering for Advanced Materials Manufacture

先进材料制造场活化烧结的基础研究

• 批准号: 9978699
• 负责人: Joanna Groza
• 金额: $ 29.35万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-10-01 至 2003-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9978699&HistoricalAwards=false
• 关键词: Fundamental; Studies; Field; Activated; Sintering

The goal of this research is to address the scientific and engineering fundamentals for a new generation of field activated sintering technique (FAST) for multi-scale powders and exploit the benefits of electrical field to develop a commercially viable manufacturing process. Previous research has demonstrated that the FAST process is able to consolidate difficult to sinter powders and achieve full densification with minimal grain growth on a limited scale. This method can reduce the number of processing steps, eliminate the need for sintering aids, and can be scaled up. However, there is a lack of basic understanding, and thus the control of field effects. Therefore, the proposed work is aimed at advancing the scientific base of the new technology by modeling field effects in sintering coupled with a thorough understanding of processing-microstructure-property relationship. The specific research will comprise: (1) development of constitutive models to quantify the conduction of electrical current through sintering compacts; (2) extension of classical models for neck growth and density evolution to account for the coupling between electrical field, temperature and pressure; (3) optimization of field processing conditions to provide particular manufacturing benefits - reduced number of manufacturing steps, flexibility in powder handling, scale up capability, and (4) application of FAST for processing advanced materials (e. g., nanocrystalline). It is anticipated that the results of this research program will not only enhance the scientific foundation of field assisted sintering phenomena but also provide quantitative insights into the relevant mechanisms for developing cost effective, large scale FAST manufacturing processes for the U.S. industry. Educational opportunities for graduate and undergraduate students include coursework and lab modules for netshape processing of sintered product with this new technology at the two institutions involved.

这项研究的目标是解决新一代多尺度粉末的场活化烧结技术(FAST)的科学和工程基础，并利用电场的优势开发出一种商业上可行的制造工艺。以前的研究表明，快速工艺能够固结难烧结的粉末，并在有限规模上以最小的晶粒长大实现完全致密化。这种方法可以减少工艺步骤，消除对烧结助剂的需要，并且可以放大。然而，缺乏基本的认识，因此缺乏对场效应的控制。因此，拟议的工作旨在通过对烧结场效应的建模以及对工艺-组织-性能关系的透彻理解来提高新技术的科学基础。具体的研究将包括：(1)开发本构模型，以量化通过烧结体的电流传导；(2)扩展颈长和密度演变的经典模型，以考虑电场、温度和压力之间的耦合；(3)优化现场工艺条件，以提供特殊的制造好处--减少制造步骤的数量、粉末处理的灵活性、扩大能力，以及(4)将FAST应用于加工先进材料(例如纳米晶体)。预计该研究项目的结果不仅将增强现场辅助烧结现象的科学基础，还将为美国工业开发具有成本效益的大规模快速制造工艺的相关机制提供量化的见解。研究生和本科生的教育机会包括两个相关机构的课程作业和实验模块，用于使用这种新技术对烧结产品进行网状加工。