Abstract: The effect of solution treatment at 1 050 - 1 150℃ on structure and mechanical properties of 1. 0 mm cold rolled plate of nickel base alloy 690 (% ： 0. 020C, 29. 93Cr, 9. 82Fe, 0. 19A1, 0. 25Ti, 0. 023Nb, 0. 012Mo, 0. 004 2N) melted by a 20 kg vacuum induction furnace has been studied. Results show that with increasing temperature of solution treatment from 1 050 Y to 1 100 ℃ the average grain size of steel linearly increases from 12 μm to 29 μm, with the temperature being more than 1 100 °C , the grain size increases rapidly and the average grain size is up to 58 at 1 150 ℃； as solution treatment temperature is more than 1 090 °C , the chromium-rich carbides in alloy dissolve completely; the fine grained strengthening is main strengthening mechanism of alloy 690, with increasing solution temperature, the ambient tensile and yield strength of alloy decrease respectively from 780 MPa and 400 MPa to 662. 5 MPa and 250 MPa, while the elongation of alloy increases from 40% to 51. 75%.

Key words:  , Nickel Base Alloy 690, Solution Treatment, Structure, Mechanical Properties

摘要： 研究了1050～1150℃固溶处理对20 kg真空感应炉熔炼的690镍基合金(%:0.020C、29.93Cr、9.82Fe、0.19Al、0.25 Ti、0.023Nb、0.012Mo、0.004 2N)1.0mm冷轧板的组织和力学性能的影响。结果表明,当固溶温度从1050℃提高至1100℃,平均晶粒尺寸呈线性增长,从12μm提高到29μm,超过1100℃时晶粒尺寸快速增长,1150℃时平均晶粒尺寸达58μm;1090℃以上固溶处理时,合金中富铬碳化物完全溶解;690镍基合金主要强化机制为细晶强化,随固溶温度升高,合金室温抗拉和屈服强度分别从780 MPa和400 MPa降至662.5 MPa和250MPa,伸长率由40%提高至51.75%。

关键词: 690镍基合金, 固溶处理, 组织, 力学性能