[KSCI] Korea Science Citation Index Service

Evaluation of Notch Location Effect on Ductile Crack Initiation at Strength Mismatched Joints by Finite Element Method and Ultrasonic-Mechatronics System

An Gyu-Baek (Institute of Industrial Technology Welding Research Part, Samsung Heavy Industries Co., LTD.)
Bang Han-Sur (Dept. of Architecture & Ocean Eng., Chosun University)
Toyoda Masao (Graduate School of Engineering, Osaka University)

Publication Information

Journal of Welding and Joining / v.23, no.6, 2005 , pp. 87-92 More about this Journal

Abstract

It has been well hewn that ductile fracture of steels is accelerated by triaxial stresses. The characteristics of ductile crack initiation in steels are evaluated quantitatively using a two-parameters criterion based on equivalent plastic strain and stress triaxiality. The present study focuses on the effects of strength mismatch, which can elevate plastic constraint due to heterogeneous plastic straining, on the critical condition for ductile fracture initiation usinga two-parameter criterion. Fracture initiation testing has been conducted under static loading using notched round bar specimens which had different notch locations. This study provides the fundamental clarification of the effect of strength mismatching and effect of notch location on the critical condition to ductile crack initiation from notch root using fuite element method and ultrasonic-mechatronics system. The critical condition of ductile crack initiation from notch root of strength mismatched tensile specimens under static loading appeared to be almost the same as those of homogeneous tensile specimens with circumferential sharp notch specimen. Also, the effect of notch location in mismatched specimens was estimated using finite element(FE) analyses.

Keywords

Ductile crack initiaion; strength mis-match; Sstress triaxiality; Equivalent plastic strain; Ultrasonic-mechatronics system;

Citations & Related Records

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