A critical evaluation and extension of internal state variables consititutive models.pdfVIP

下载本文档

5
0
约3.39万字
约 15页
2017-04-13 发布于江苏
举报
版权申诉

A critical evaluation and extension of internal state variables consititutive models.pdf

1、本文档共15页，可阅读全部内容。
2、有哪些信誉好的足球投注网站（book118）网站文档一经付费（服务费），不意味着购买了该文档的版权，仅供个人/单位学习、研究之用，不得用于商业用途，未经授权，严禁复制、发行、汇编、翻译或者网络传播等，侵权必究。
3、本站所有内容均由合作方或网友上传，本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺！文档内容仅供研究参考，付费前请自行鉴别。如您付费，意味着您自己接受本站规则且自行承担风险，本站不退款、不进行额外附加服务；查看《如何避免下载的几个坑》。如果您已付费下载过本站文档，您可以点击这里二次下载。
4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等，请点击“版权申诉”（推荐），也可以打举报电话：400-050-0827(电话支持时间：9:00-18:30)。
5、该文档为VIP文档，如果想要下载，成为VIP会员后，下载免费。
6、成为VIP后，下载本文档将扣除1次下载权益。下载后，不支持退款、换文档。如有疑问请联系我们。
7、成为VIP后，您将拥有八大权益，权益包括：VIP文档下载权益、阅读免打扰、文档格式转换、高级专利检索、专属身份标志、高级客服、多端互通、版权登记。
8、VIP文档为合作方或网友上传，每下载1次，网站将根据用户上传文档的质量评分、类型等，对文档贡献者给予高额补贴、流量扶持。如果你也想贡献VIP文档。上传文档

A critical evaluation and extension of internal state variables consititutive models

Pergamon International Journal of Plasticity, Vol. 11, No. 4, pp. 33 i-345, 1995 Copyright ? 1995 Elsevier Science Ltd Printed in the USA. All rights reserved 0749-6419/95 $9.50 + .00 0749-6419(95)00002-X A C R I T I C A L E V A L U A T I O N A N D E X T E N S I O N O F I N T E R N A L STATE V A R I A B L E S C O N S T I T U T I V E M O D E L S HuI LI,* SUNIL SAIGAL,* P. T. WAN~,I and H. R. PIEI-ILER* *Carnegie Mellon University and tALCOA Technical Center (Communicated by Michael G. Stout, Los Alamos National Laboratory) Abstract-This study provides a critical comparison of the internal state variables constitutive models proposed recently in the literature for metals at elevated temperatures and deformed over a wide range of strain rates. As a result of the observations from this comparative evaluation, a set of modified constitutive relations is also presented. The experimental data available in the ]literature for 1100 aluminum and a fully dense high purity aluminum were used along with a Jaonlinear least squares fitting procedure to estimate the material constants. A nonlinear func- r.ional dependence of the effective stress with respect to the internal state variable in the evolu- ~Lion relationship was determined to model more effectively, compared to previous models, the case that a material may exhibit both hardening and softening behaviors, respectively, corre- .sponding to different applied strain rates at the same temperature. The modified relations pre- sented here propose a simple form of this nonlinear function, which accurately models the :material response and which allows a more robust implementation in numerical simulations. The deformation of an aluminum gradient specimen was studied for further comparison of the three constitutive models considered and for a demonstration of the validity of this model. 1. INTRODUCTION The deformation processing of metals commonly involves hot working operations to fabricate th