Abstract: Effect of solid-solution treatment on microstructure and impact properties of solid-solution + aged UNS N07718  alloy[/%:0.03C,52.5Ni,18.0Cr,3.0Mo,5.0(Nb+Ta),0.90Ti,0.50Al] are investigated.After960℃ solid-solution + aging treatment, the δ phase diffusely distributes on the grain boundaries and in the grains, and the grains are relatively uniform and fine with impact energy 17J.After1000℃+960℃ solid-solution+aging treatment, the size of δ phase distributed on the grain boundaries becomes larger ,and the grain size is slightly increased.After1010℃+960℃ solid-solution aging treatment, the phase& are dissolved, and only a little of δphase is located at the grain boundaries, while the grain size is increased evidently.After1020℃+960℃ solid-solution+aging treatment, the granular δ phases are disappeared.After1010℃+960℃solid-solution+agingtreatment,the impact energy of sample is 43J and a 150% increase in the impact energy, compared with 960℃ aged in addition, the fracture morphologies of the sample surface exhibit a number of dimples obviously.

Key words: UNS N07718 Alloy;Solid-Solution Temperature;Microstructure, Impact Property

摘要： 研究了固溶处理对固溶-时效UNS N07718合金[/%:0.03C, 52.50Ni, 18.0Cr, 3.0Mo, 5.0(Nb+Ta), 0.90Ti, 0.50Al]显微组织及冲击性能的影响。960℃+时效处理后，针状δ相弥散分布于晶内和晶界，晶粒尺寸均匀细小，冲击功17 J;1 000℃+960℃+时效处理后，δ相尺寸增大呈针片状分布于晶界处，数量减少，晶粒尺寸增大;1 010℃+960℃+时效处理后，δ相由针状转变为颗粒状，断续分布于晶界，晶粒明显长大;1 020℃+960℃+时效处理后，颗粒状δ相全部溶解。1 010℃+ 960℃+时效处理后，样品冲击功为43 J，相较于960℃+时效，冲击功提升150%，且冲击断口呈现明显的韧窝结构。

关键词: UNS NO7718合金, 固溶温度, 显微组织, 冲击性能