关键词: 双相不锈钢, 2205, 高温腐蚀

Abstract: The objective of this study was to figure out the hot corrosion behavior of 2205 duplex stainless steel(2205 DSS) within the temperature ranges from 550 to 850℃ in the static air condition with 2 mg/cm~(2)NaCl deposit,and in the air atmosphere condition with a constant flow rate of 500 vppm NaCl_((g)),respectively.Experimental results show that the hot corrosion kinetics met the parabolic rate law and the corrosion rate increased constantly with increasing temperature.The scales formed included Fe_(2)O_(3)/Fe_(3)O_(4)/Cr_(2)O_(3) and FeCr_(2)O_(4)from outer layer to inner layer.The sequence of formation is independent of the environment temperature,but the SiO_2 and NiO can be found in the substrate of 850℃specimen.The corrosion sequence in two phase structure of 2205 DSS was not influenced by α and γ phases in the 2 mg/cm~(2)NaCl deposit due to complete corrsion and in the air atmospheres condition with a constant flow rate of 500 vppm NaCl_((g)).In the case of constant flow rate of 500 vppm NaCl_((g)),the corrosion rate in the γ phase was greater than that in the α phase,although the corrosion sequence was not known.

Key words: Duplex stainless steel, 2205DSS, High-temperature corrosion