Effect of Preheat Temperature on Diffusible Hydrogen Content in Weld Metal Deposited using Flux Cored Wire

Kim, Dong Yoon; Hwang, In Sung; Kim, Dong Cheol; Kang, Moon Jin

doi:2014.32.2.144

J Weld Join > Volume 32(2); 2014 > Article

Special Issue

Journal of Welding and Joining 2014;32(2):144-147.
DOI: https://doi.org/10.5781/JWJ.2014.32.2.18 Published online May 14, 2014.

Effect of Preheat Temperature on Diffusible Hydrogen Content in Weld Metal Deposited using Flux Cored Wire

Dong Yoon Kim^*, In Sung Hwang^*, Dong Cheol Kim^*, Moon Jin Kang^*

Correspondence: Dong Cheol Kim,
Email: dckim@kitech.re.kr

Abstract

Cold cracking of weldment is one of the most serious welding problems. A sufficient quantity of diffusible hydrogen, a residual stress, and a sensitive microstructure are the causes of cold cracking. Removal of any one of these factors can be used to prevent cold cracking. Application of flux cored arc welding process is increasing due to high productivity and easiness of welding. In addition, to prevent cold cracking in the HAZ or weldment, preheat temperature and interpass temperature have to be controlled. In this study, the effect of preheat temperature on the levels of diffusible hydrogen in the weld metal deposited using flux cored wire was examined. The levels of preheat temperature of base metal specimen were ambient temperature, 50, 100 and 150 ℃ respectively. The result showed that the increase of preheat temperature was a linear relationship with reduction of diffusible hydrogen content in weldment.

Key Words: Diffusible hydrogen content, Hydrogen induced cracking, Flux cored wire, Preheat temperature, Delay time