Component Shape Retention in Liquid Phase Sintering of Prealloyed Powders

预合金粉末液相烧结中的部件形状保持

• 批准号: 9610280
• 负责人: Randall German
• 金额: $ 29.26万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-03-01 至 2000-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9610280&HistoricalAwards=false
• 关键词: Component; Shape; Retention; Liquid; Phase

9610280 German New research on supersolidus liquid phase sintering (SLPS) addresses three topics. The first examines microstructural evolution during heating and sintering. A current model of the process makes assumptions on the rate of grain growth, liquid film thickness, shrinkage rate, semisolid particle viscosity, and causes of distortion. These assumptions are addressed by experimentation performed on model systems using microstructure measurements from quenched samples and in situ testing. The goal is to increase the model reality and to recognize any behavior between systems. The second topic is the prediction of final component size and shape. A computational prediction for the loss of structural rigidity as liquid spreads on the grain boundaries needs verification. Furthermore, gradients in grain size, particle size, packing density, substrate friction, and heat transfer need to be included in the final component size and shape predictions. The third activity extends the model to several other processing conditions (bimodal-sized powders, powders of differing compositions, high viscosity systems, reactive systems). %%% Success in this research should positively impact the use of the SLPS process to produce full density, complex shapes via powder metallurgy. A research target is tool steels where there are opportunities to use SLPS in the near net-shape production of high performance tooling. ***

9610280德国关于Supersolidus液相烧结（SLP）的新研究介绍了三个主题。 第一个检查在加热和烧结过程中的微观结构演变。 该过程的当前模型对晶粒生长速率，液体膜厚度，收缩率，半固体颗粒粘度和失真原因进行了假设。 这些假设是通过使用淬灭样品和原位测试的微观结构测量对模型系统进行的实验来解决的。 目的是增加模型现实并认识系统之间的任何行为。 第二个主题是最终组件大小和形状的预测。 随着液体在晶界扩散的结构刚度丧失的计算预测需要验证。 此外，需要包括在最终的组件尺寸和形状预测中的晶粒尺寸，粒径，堆积密度，底物摩擦和传热的梯度。 第三个活动将模型扩展到其他几种处理条件（双峰大小的粉末，不同组成的粉末，高粘度系统，反应性系统）。 在这项研究中，成功​​的成功应对SLP工艺的使用积极影响通过粉末冶金产生全密度，复杂形状。 研究目标是工具钢，其中有机会在高性能工具的近乎净形生产中使用SLP。 ***