Thermal input effect of duplex stainless steel

Unlike the weld zone, the ω (N) of the heat affected zone will not change during welding, which is the ω (N) of the base material, so the main factor affecting the structure and performance at this time is the heat input during welding. According to the literature, the appropriate line energy should be selected during welding. During welding, if the heat input is too large, the heat-affected zone of the weld will increase, and the metallographic structure will also tend to be coarse and disorganized, resulting in embrittlement, which is mainly manifested by the decrease of the plastic index of the welded joint. If the welding heat input is too small, it will cause the hardened structure and easy to crack, which is also unfavorable to the impact toughness of HAZ. In addition, all the factors that affect the cooling rate will affect the impact toughness of HAZ, such as plate thickness and joint form.