Effect of thermal aging on the mechanical, intergranular corrosion and corrosion fatigue properties of Z3CN20.09M cast duplex stainless steel

• Main Authors: Wenxin Ti, Huanchun Wu, Fei Xue, Guodong Zhang, Qunjia Peng, Kewei Fang, Xitao Wang
• Format: Article
• Language: English
• Published: Elsevier 2021-08-01
• Series: Nuclear Engineering and Technology
• Subjects: Thermal aging; Spinodal decomposition; Sigma precipitation; Corrosion fatigue; High temperature water
• Online Access: http://www.sciencedirect.com/science/article/pii/S1738573321000632
• ISSN: 1738-5733

The effect of thermal aging at 475 °C and 750 °C of Z3CN20.09M cast duplex stainless steel (CDSS) on microstructure, mechanical and intergranular corrosion properties were investigated by transmission electron microscope (TEM), nano indenter, scanning electron microscope (SEM) and corrosion fatigue test system. The result indicated that the spinodal decomposition and G precipitated were occurred after aged at 475 °C, as well as sigma precipitated at 750 °C. The microstructure degeneration of ferrite was saturated after aged for 2000h and 200 h at 475 °C and 750 °C respectively. The mechanical properties, intergranular corrosion resistance and corrosion fatigue lives were continuing deteriorated with increasing the aging time at both temperatures. The difference of the degeneration mechanisms of Z3CN20.09M CDSS aged at 475 °C and 750 °C was analyzed.