Effect of heat input on austenite microstructural evolution of simulated heat affected zone in 2205 duplex stainless steel
Tian-hai Wu 1,2 ， Jian-jun Wang 1,2 ， Hua-bing Li 3 ， Zhou-hua Jiang 3 ， Chun-ming Liu 1,2 ， Hong-yang Zhang 4
1 Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Northeastern University, Shenyang 110819, Liaoning, China 2 School of Materials Science and Engineering, Northeastern University, Shenyang 110819, Liaoning, China 3 School of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, China 4 Shenyang Northeastern Institute of Metal Materials Co., Ltd., Shenyang 110108, Liaoning, China
Effect of heat input on austenite microstructural evolution of simulated heat affected zone in 2205 duplex stainless steel
Tian-hai Wu 1,2 ， Jian-jun Wang 1,2 ， Hua-bing Li 3 ， Zhou-hua Jiang 3 ， Chun-ming Liu 1,2 ， Hong-yang Zhang 4
1 Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Northeastern University, Shenyang 110819, Liaoning, China 2 School of Materials Science and Engineering, Northeastern University, Shenyang 110819, Liaoning, China 3 School of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, China 4 Shenyang Northeastern Institute of Metal Materials Co., Ltd., Shenyang 110108, Liaoning, China
摘要 The effect of simulated welding thermal cycle on the microstructure and impact toughness of heat affected zone (HAZ) in 2205 duplex stainless steel was investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy and room temperature impact test. The results show that the morphology and volume fraction of austenite change greatly with heat input. The amount of residual austenite and grain boundary austenite (GBA) decreases while Widmansta¨tten austenite (WA) laths and intergranular austenite increase with the increase in heat input. Only the fine equiaxed austenite exists in the HAZ when the heat input is increased up to 61.8 kJ/cm. WA laths nucleate initially either at the ferrite and GBA phase boundaries or directly in ferrite grains and begin to decompose into diamond-shaped austenite with the heat input larger than 25.2 kJ/cm. The impact toughness shows a non-monotonic variation, which is related to the increase in austenite fraction and the formation and the decomposition of WA laths.
Abstract：The effect of simulated welding thermal cycle on the microstructure and impact toughness of heat affected zone (HAZ) in 2205 duplex stainless steel was investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy and room temperature impact test. The results show that the morphology and volume fraction of austenite change greatly with heat input. The amount of residual austenite and grain boundary austenite (GBA) decreases while Widmansta¨tten austenite (WA) laths and intergranular austenite increase with the increase in heat input. Only the fine equiaxed austenite exists in the HAZ when the heat input is increased up to 61.8 kJ/cm. WA laths nucleate initially either at the ferrite and GBA phase boundaries or directly in ferrite grains and begin to decompose into diamond-shaped austenite with the heat input larger than 25.2 kJ/cm. The impact toughness shows a non-monotonic variation, which is related to the increase in austenite fraction and the formation and the decomposition of WA laths.
Tian-hai Wu,Jian-jun Wang,Hua-bing Li, et al. Effect of heat input on austenite microstructural evolution of simulated heat affected zone in 2205 duplex stainless steel[J]. Journal of Iron and Steel Research International, 2019, 26(5): 435-441.
2019, Vol. 26 
