固溶时效对 Inconel718合金组织和力学性能的影响

摘要

Solid solution treatment from 920 ℃ to 1 060 ℃ for 1.5 h and aging treatment from 650 ℃ to 850 ℃ for 6 - 10 h were carried out on Inconel718 alloy, the effects of solid solution temperature, aging temperature and aging time on microstructure and mechanical properties of the alloy were studied.At last,a appropriate heat treatment process was obtained.The results show that, comparing with solid solution, the hardness of the alloy was obviously improved after aging treatment.With the increase of solid solution temperature, austenite grain grew and δphase dissolved gradually.The suitable solid solution temperature was 1 000-1 020 ℃. With the increase of aging time,dispersion strengthening of precipitated phases in the alloy was better,and yield ratio increase signally.After solid solution treatment at 1 000-1 020 ℃ and aging treatment at 750 ℃ for 10 h,the mechanical properties of the alloy was optimum,tensile strength,impact absorption energy at room temperature and hardness was more than 1 200 MPa,120 J and 310 HV10,respectively.%对 Inconel718合金进行了(920~1060℃)×1．5 h＋(650~850)℃×(6~10)h 的固溶时效处理,研究了固溶温度和时效温度、时间对合金组织和力学性能的影响,并获得了较理想的固溶时效工艺.结果表明：时效处理后,合金的硬度较固溶态的明显提高；随固溶温度升高,奥氏体晶粒长大,δ相逐渐溶解,较适宜的固溶温度为1000~1020℃；随时效时间延长,合金中析出相的弥散强化效果更佳,屈强比提高显著；在1000~1020℃固溶＋750℃×10 h 时效处理后,合金的力学性能最佳,抗拉强度超过1200 MPa,室温冲击吸收功超过120 J,硬度超过310 HV10.