Improving the Toughness of Heat Affected Zone of Steel Plate by Use of Fine Inclusion Particles

Abstract

Abstract There are two kinds of mechanisms of the improvement of Heat Affected Zone(HAZ) toughness with fine inclusion particles. One is to prevent the austenite grain growth during welding process with the aid of the pinning effect of fine particles. The other is to promote the Intragranular Ferrite growth during phase transformation process with fine particles. The oxide metallurgy technology with strong deoxidizers is developed in Baosteel. With the pinning effect of fine particles, after welding with high‐heat input of 400 kJ/cm, the average austenite grain size decreased to 61 µm in HAZ, the average energy absorbed value increased to 142 J for V notch Charpy test at 1653 K.