Rheological model for viscous flow densification during supersolidus liquid phase sintering

Author:

German R.M.1

Affiliation:

1. Center for Advanced Vehicular Systems, Mississippi State

Abstract

A model is derived for the viscous flow densification of prealloyed powders heated to just over the solidus temperature, a process termed supersolidus liquid phase sintering. The model builds from the viscous flow concepts first introduced by Frenkel with a new porosity effect. Viscous flow densification starts with the formation liquid on the grain boundaries inside the particles, with subsequent spreading of liquid to form a capillary bond between contacting particles. Pores lower the initial semisolid viscosity, but as densification progresses the viscosity increases. On the other hand, viscosity decreases higher temperatures increase. Densification is induced by the capillary force acting against the semisolid system, but densification is delayed until the particles sufficiently softened from liquid spreading on the grain boundaries. Thus, both viscosity and strength vary with the liquid content and particle microstructure. Distortion in sintering traces to an excess of liquid that lowers the skeletal rigidity, mainly due to grain growth with a concomitant release of grain boundary liquid. This often occurs after full densification is achieved. This modification to the model includes the correction for porosity effects on viscosity. The model is compared with data on a 316L stainless steel doped with boron, subjected to in situ densification and slumping observations. .

Publisher

National Library of Serbia

Subject

Materials Chemistry,Metals and Alloys,Condensed Matter Physics,Ceramics and Composites

Cited by 17 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3