抄録
It is now questionable that the Liquid-Metal-Embrittlement-cracking (LME-cracking) rises in HAZ of welds of steel structure during hot dip galvanizing. Because of preventing the cracking, it is necessary to study the effect of welding factors on the critical stress of steel in molten zinc (σcr).
In this report, the tensile tests were carried out in molten zinc by using the welding joint specimen with U notch in HAZ, and σcr for each materials used was investigated. The results are as follows.
(1) σcr decreased as the stress concentration (Kt) was large, but it was approximately constant over Kt=3.
(2) As the heat input was large, grain size at coarse-grained region was large, maximum vickers hardness in HAZ was lower and σcr increased.
(3) σcr was linearly arranged by using maximum vickers hardness in HAZ.
