Local Strain Energy Density Applied to Bainitic Functionally Graded Steels Plates Under Mixed-Mode(Ⅰ+Ⅱ) Loading

作     者：H.Salavati Y.Alizadeh F.Berto 

作者机构：Department of Mechanical Engineering Amirkabir University of Technology Department of Management and Engineering University of Padova 

出 版 物：《Acta Metallurgica Sinica(English Letters)》 (金属学报（英文版）)

年 卷 期：2015年第28卷第2期

页      面：164-172页

核心收录：

学科分类：0817[工学-化学工程与技术] 0806[工学-冶金工程] 08[工学] 0807[工学-动力工程及工程热物理] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0802[工学-机械工程] 0703[理学-化学] 0811[工学-控制科学与工程] 

主　　题：Functionally bainitic graded steel Strain energy density Mechanism-based strain gradientplasticity theory Critical load Notch radius Notch depth 

摘      要：In this paper, the averaged value of the strain energy density （SED） over a control volume is used to predict the critical load of V-notched specimens made of functionally graded steels （FGSs） under mixed-mode loading. The studied FGSs contain ferritic and austenite phases in addition to bainitic layer produced by electroslag remelting. The mechanism- based strain gradient plasticity theory is used to determine the flow stress （yield stress or ultimate stress） of each layer. The Young＇s modulus and the Poisson＇s ratio have been assumed to be constant, while other mechanical properties vary exponentially along the specimen width. The control volume is centered in relation to the maximum principal stress present on the notch edge and assumes a crescent shape. The points belonging to the volume perimeter are obtained numerically. In the present contribution, the effects of notch radius and notch depth on the SED and the critical load are studied. The notch radius varies from 0.2 to 2.0 mm, and the notch depth varies from 5 to 7 ram. By using the SED approach and finite element simulations, the critical load is determined, and the obtained results show a sound agreement with the experimental results.