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德国超固相烧结（SLPS）的新研究涉及三个主题。第一个研究在加热和烧结过程中微观结构的演变。该过程的当前模型对晶粒生长速率、液膜厚度、收缩率、半固态颗粒粘度和变形原因进行了假设。这些假设是通过使用淬火样品的微观结构测量和原位测试对模型系统进行的实验来解决的。目标是增加模型的真实性，并识别系统之间的任何行为。第二个主题是最终零件尺寸和形状的预测。液体在晶界上扩散时结构刚度损失的计算预测需要验证。此外，晶粒尺寸、颗粒尺寸、堆积密度、衬底摩擦和传热的梯度需要包括在最终的组件尺寸和形状预测中。第三种活动将模型扩展到其他几种加工条件（双峰尺寸粉末，不同成分粉末，高粘度体系，反应体系）。这项研究的成功将对SLPS工艺通过粉末冶金生产全密度、复杂形状的应用产生积极影响。研究目标是工具钢，其中有机会在高性能工具的近净形状生产中使用SLPS。＊＊＊