Open AccessExperiment and Numerical Modeling of Boron Effect on Weld HAZ Hardenability of Steels
Author(s) -
Keitaro Yoshimoto,
Timotius Pasang,
Shuji Aihara,
Tomoya Kawabata
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/894/1/012017
Subject(s) - hardenability , boron , materials science , metallurgy , weldability , grain boundary , welding , microstructure , toughness , heat affected zone , alloy , chemistry , organic chemistry
Boron is an alloying element used for increasing the strength of steels, but on the other hand, it sometimes deteriorates heat affected zone (HAZ) weldability and toughness. Although it is widely known that the hardenability of steel is improved due to grain boundary segregation of boron, its details and quantification have not yet been clarified. In this study, boron-free HT590 and boron-added HT780 steels were welded and microstructure and hardness distribution in HAZ were measured, in detail. Furthermore, we calculated and investigated the grain boundary segregation and diffusion of boron during weld thermal cycle by numerical analysis while comparing it with the experiment result. As a result, the present model made it clear that the effect of boron on HAZ hardenability can be expressed by non-equilibrium segregated boron at grain boundary, quantitatively.