时效工艺对2507不锈钢σ相析出及力学性能的影响

Effect of aging process on σ-phase precipitation and mechanical properties of 2507 stainless steel

通过拉伸、硬度、冲击试验研究了时效温度、时间对2507超级双相不锈钢力学性能的影响,并应用EBSD技术观察了σ相的析出。结果表明：在900-1000℃区域,随时效温度降低,σ相析出量增加,材料塑性变差,温度低于940℃时效10 min其伸长率低于10%;在600-700℃区域,随时效温度升高,σ相析出量增加,但析出时间较高温区域长,力学性能恶化不太严重,600-650℃时效40 h内伸长率〉20%,冲击吸收能量〉10 J。

Effects of aging temperature and time on mechanical properties of 2507 super duplex stainless steel were studied by means of tensile,hardness and impact tests,and the precipitation of the σ phase was observed by means of EBSD. The results show that with the decrease of aging temperature,the precipitation of the σ-phase increases and the plasticity of the material becomes worse at 900-1000 ℃region,the elongation is lower than 10% under the condition of aging temperature below 940 ℃ and aged for 10 min. At 600-700 ℃ region,with the increase of aging temperature,the precipitation of the σ-phase increases,but the aging time is greatly prolonged compared with that the higher temperature region,and the deterioration of mechanical properties is not very serious,the elongation is higher than 20% and impact absorbed energy is higher than 10 J under the aging condition of 600-650 ℃ and 40 h.