Explanation

Under the action of weld heat source, there are obvious changes in structure and properties on both sides of the weld. Due to the different thermal cycles experienced by each point of weld heat effect, which is equivalent to the heat treatment of different maximum heating temperatures at different locations, the structure and properties are also significantly different. The heat affected zone of steel with low hardenabilhy can be divided into fusion zone, overheating zone, normalizing zone and part of phase transformation zone; The heat effect of steel with higher hardenabilhy can be divided into complete quenching zone and incomplete quenching zone.

Classification